Hello Everyone yesterday I was looking through Facebook Market Place and I saw what appears to be an old Meck TV for sale on there for sale on there for $5 and I was wondering if I should go and get it or not at that price, because I know the old Meck TVs are fairly rare TVs in any condition and this one appeared to be all there and in really good shape (no peeling veneer or water damage and the picture tube looked good yet).

Pictures of the unit in question is posted below.

What do you guys think? Should I pop for it at $5?

At 5 you can get your money back parting it out if you need...If the CRT is good that is a cnote to someone in need.

Mounts (edit my phone's autocorrect apparently thinks the name Muntz must be replaced with the word mounts or mints :lmao: ) sets are simple to recap and make basically work, but if you expect really good scan geometry/linearly or perfect performance you will either never achieve it or drive your self nuts trying to find the right combination of tubes it likes and changing all the resistors and other similar things...


Muntzes are like 2-4 tube AM radios... they receive the signal under the right conditions but don't out perform other sets of their time (often even when the other sets are getting close to needing repair).

Hello Everyone yesterday I was looking through Facebook Market Place and I saw what appears to be an old Muntz TV for sale on there for sale on there for $5 and I was wondering if I should go and get it or not at that price, because I know the old Muntz TVs are fairly rare TVs in any condition and this one appeared to be all there and in really good shape (no peeling veneer or water damage and the picture tube looked good yet).

Pictures of the unit in question is posted below.

What do you guys think? Should I pop for it at $5?

That's not a Muntz, it's a Meck. Made in Plymouth,Indiana, possibly rarer! :scratch2:

That's not a Muntz, it's a Meck. Made in Plymouth,Indiana, possibly rarer! :scratch2:

Even Better, because I have relatives that live near there and my dad is from Culver, Indiana which is just up the road from Plymouth, Indiana.

At 5 bucks I'd already have it in the back of my car! :yes:
Get it, before some fishtanker does.

I would also be picking up whatevers beside it.......

At 5 bucks I'd already have it in the back of my car! :yes:
Get it, before some fishtanker does.

I would also be picking up whatevers beside it.......

I think the set next to it is probably a small screen electromagnetic deflection Motorola (based on the chassis glimpse) those are nice too if pricing is fair.

What Tom-and Tube TV said...

I'll be going over there tomorrow to check it out, and I'll definitely check out the other TV next to it and see if they want to get rid of that as well and maybe do a bundle deal.

By the way they do have the knob for the TV that is missing in the picture.

Well I got the TV today, it said Philharmonic on the front of it, and its missing the Power switch/Volume control knob and the fine tuning knob for the tuner, and the back cover and the channel display panel for the tuning knob.

Other than that its complete.

It has a 12P4 Picture tube which looks like its in really good shape yet. :yes:

I actually got a bonus piece thrown in for free, an old Westinghouse Columnette Tombstone Radio that the cabinet is shot on it but the chassis and speaker is still in excellent shape yet with all of its original tubes in it yet, and its original cloth cord still intact yet. I'll add pictures when I get a chance.

Philharmonics are rarely seen too. It's not the most unique looking early TV, but the odd-brand name and roundie screen make it certainly worth getting, preserving, and having it performing again. The low price make it a no-brainer. Good luck with it!

Whomever made it they sure adhered to a minimal circuit approach. Or maybe the tubes are all scrunched up towards the front of the chassis? In any event it's an interesting find. Looking forward to more detailed pictures. :thmbsp:

I took a closer look at the TV set yesterday and just like DieselJeep said it is a Meck TV.
I'm guessing the Philharmonic Designation on the front of the TV was the model name of the TV.
All of the tubes that were present in the TV still were all badged Meck and actually this TV has way more tubes in it than it looks like it has, they are just mostly in the front of the cabinet and inside the High Voltage Cage.

This TV actually has an interesting Story behind it, the person I bought it from found the TV in a really old farm house that the roof had collapsed on it 20 years ago and the TV some how managed to survive all that time in really good shape (the cabinet didn't rot or anything and the chassis and the tubes aren't horribly rusted away or anything).

I think that what saved this TV from degrading too badly was that the cabinet on this TV was actually Solid Wood and not just veneered plywood like what they did with the old radios from that period.

Glad to hear you got it! This gives us all a bit of hope that there are still a few neat sets out there a a fair price.
Look forward to seeing some more pictures of it.

I took a closer look at the TV set yesterday and just like DieselJeep said it is a Meck TV.
I'm guessing the Philharmonic Designation on the front of the TV was the model name of the TV.
All of the tubes that were present in the TV still were all badged Meck and actually this TV has way more tubes in it than it looks like it has, they are just mostly in the front of the cabinet and inside the High Voltage Cage.

This TV actually has an interesting Story behind it, the person I bought it from found the TV in a really old farm house that the roof had collapsed on it 20 years ago and the TV some how managed to survive all that time in really good shape (the cabinet didn't rot or anything and the chassis and the tubes aren't horribly rusted away or anything).

I think that what saved this TV from degrading too badly was that the cabinet on this TV was actually Solid Wood and not just veneered plywood like what they did with the old radios from that period.
Whether Meck, Muntz, or Philharmonic, they were all budget TV's. These secondary companies sales edge was making them seem like bargain through bare-bones electronics. The funny thing is these sets often perform just fine. Today, as a collectible, these more unusual sets appeal to collectors more than the popular named sets. I have a friend who owns a 7" combo console Philharmonic. It looks pre-war. It'll be one of the last TV sets he parts with!

Whether Meck, Muntz, or Philharmonic, they were all budget TV's. These secondary companies sales edge was making them seem like bargain through bare-bones electronics. The funny thing is these sets often perform just fine. Today, as a collectible, these more unusual sets appeal to collectors more than the popular named sets. I have a friend who owns a 7" combo console Philharmonic. It looks pre-war. It'll be one of the last TV sets he parts with!
Meck made TV's with other private labels too. Spiegel's Aircastles and even those so-called custom sets badged Radio-Craftsman.
Meck bought the E.H. Scott radio name in the late 40's or early 50's. :scratch2:

Meck made TV's with other private labels too. Spiegel's Aircastles and even those so-called custom sets badged Radio-Craftsman.
Meck bought the E.H. Scott radio name in the late 40's or early 50's. :scratch2:

Ok that makes sense as to why it would be a Meck and have the E. H. Scott Philharmonic name plate on it. :scratch2::thmbsp:

OK so I was finally able to get the chassis out of my Meck/Philharmonic TV and repopulated the chassis with known good tubes from my tube stash and plugged it in to test it out and when I turned the TV on all of the tubes including the Picture tube started glowing but then a few seconds later the 5U4G Rectifier tube for the power supply starting sparking and arcing inside so I quickly turned it off and unplugged it.

Any ideas as to what could be causing the arcing 5U4G Rectifier tube? thats the only tube in the whole TV that was arcing the rest of the tubes were working fine.

I did notice that the Power supply filter caps (which are in a cardboard can) was snapped off from its phenolic wafer that held it to the chassis (the phenolic mounting wafer that the capacitor can was mounted to itself was snapped off from the chassis not the capacitor can itself).

Here are some pictures of the chassis of this TV showing the Tubes.

It is super obvious. You shouldn't have to ask. One or more of the lytics is almost certainly shorted.

Most sets made before the mid 60s will not work or eventually kill themselves if all the lytics and paper caps are not changed.
The only reason to power up before a recap is on the off chance it works you have a baseline to see if you make a mistake and add a new problem when you recap it immediately after.

It is super obvious. You shouldn't have to ask. One or more of the lytics is almost certainly shorted.

Most sets made before the mid 60s will not work or eventually kill themselves if all the lytics and paper caps are not changed.
The only reason to power up before a recap is on the off chance it works you have a baseline to see if you make a mistake and add a new problem when you recap it immediately after.

Well I was trying to power it up to see what kind of working order it was in. I figured it was going to need new capacitors but I wasn't sure.

Here are some pictures of the chassis of this TV showing the Tubes.

How does the underside of the chassis look? The top shows signs of having been a rodent hotel at one time.

How does the underside of the chassis look? The top shows signs of having been a rodent hotel at one time.

This TV as I had stated previously had sat in an old abandoned farm house that its roof had collapsed on it 20 years prior and the TV sat in those conditions for 20 years prior to it being found by the person I had gotten the TV from.

The TV's Cabinet is actually in immaculate condition and was just really dirty despite it sitting in the conditions it had sat in for as long as it had, the undercarriage of the TV is also extremely clean for the conditions the TV had sat in.

Unfortunately the Westinghouse Radio I had gotten from the same person which came out of the same place wasn't so lucky and its cabinet was trashed but oddly enough even inspite of a little rust on the chassis (which cleaned right off with some #00 grade steel wool) the radio still worked flawlessly.

Unfortunately it seems that finding the correct knobs for this TV is going to be quite tricky even with fleabay, which I found a few knobs on there that looked like a close match to the original Channel Selector knob and volume/on/off switch but nothing exactly like the original knobs, and also there didn't seem to be any channel selector escutcheons for sale on fleabay like the one I needed.

Unfortunately it seems that finding the correct knobs for this TV is going to be quite tricky even with fleabay, which I found a few knobs on there that looked like a close match to the original Channel Selector knob and volume/on/off switch but nothing exactly like the original knobs, and also there didn't seem to be any channel selector escutcheons for sale on fleabay like the one I needed.

Post a WTB on antiqueradios.com, with pictures of what they should look like if you can. I've found some knobs I never expected to be able to get that way!

Post a WTB on antiqueradios.com, with pictures of what they should look like if you can. I've found some knobs I never expected to be able to get that way!

I've had issues with that site in the past and so I would rather not deal with that site anymore, otherwise I would.

Here are some pictures of the cabinet for this TV, you'll be surprised at how immaculate the cabinet is considering this TV had sat in an old farmhouse that its roof collapsed 20 years ago.

Here are some pictures of the cabinet for this TV, you'll be surprised at how immaculate the cabinet is considering this TV had sat in an old farmhouse that its roof collapsed 20 years ago.

That is quite amazing.

Wow that's nice woodwork. Sometimes you get and get one with a nice cabinet.
This is one of those times.

Thanks! And yes I agree this is definitely a very nice cabinet, and the fact that its all solid walnut and not just veneered plywood might be why this TV cabinet survived in such good shape after all these years. :yes: :thmbsp: :D

OK so this TV's Power Supply Cap Can is a 40/40/40 @ 450 VDC I would of tried to keep the original cap in place for appearances sake but somehow the phenolic wafer that the power supply filter was attached to was snaped off at the chassis so the power supply filter cap is just hanging on the chassis by its wires and what not.

I'm thinking of mounting a small terminal strip under the chassis near where the original power supply filter cap was originally as there is a blank hole located conveniently next to where the old filter caps are that I could bolt the terminal strip to.

I'm assuming that the wires that were attached to the mounting tabs on the original can capacitor were using those as grounding terminals or junction points of some sort and aren't critical as to where they are relocated to?

Physical location of lytics usually is not critical. On cans that connect to chassis (and some that don't but run the can negative wire to convenient points) I often place the individual replacements at the point the wire to the can positive originates from even if that spot is on the far end of the chassis.

One thing to make sure of though if the can negative was insulated from the chassis and fed from one or more wires that are not directly connected to the chassis to keep that floating negative separate from the chassis...In my first year or two of restoring radios I messed up a Zenith Transoceanic replacing a floating negative lytic with individual parts that I tied the negatives of to chassis instead of the floating negative...Later I figured that mistake out and fixed it.

Physical location of lytics usually is not critical. On cans that connect to chassis (and some that don't but run the can negative wire to convenient points) I often place the individual replacements at the point the wire to the can positive originates from even if that spot is on the far end of the chassis.

One thing to make sure of though if the can negative was insulated from the chassis and fed from one or more wires that are not directly connected to the chassis to keep that floating negative separate from the chassis...In my first year or two of restoring radios I messed up a Zenith Transoceanic replacing a floating negative lytic with individual parts that I tied the negatives of to chassis instead of the floating negative...Later I figured that mistake out and fixed it.

Its a capacitor can with a cardboard tube jacketand the capacitor didn't seem to have a ground that I could see on the jacket anywhere, it gave the different shapes for each section along with the values for each section but it didn't list anything about what the negative connection was for the can.
Could it of been that they used a non-polar capacitor can for the power supply filter caps?? :scratch2:

No non-polarized lytics are not used for filter caps in these sets (sometimes single section non-polarized were used to couple the yoke and allow centering DC to be added).

If there is a metal can under the cardboard then there were negative terminals on it's bottom (they may have snapped off when it got busted off its wafer). If there is no metal can or terminals on the cap and just wires out the bottom then there has to be a negative lead if it is a multi section cap.

You need to get the schematic and trace things out if you can't make sense of the wiring that's there.

No non-polarized lytics are not used for filter caps in these sets (sometimes single section non-polarized were used to couple the yoke and allow centering DC to be added).

If there is a metal can under the cardboard then there were negative terminals on it's bottom (they may have snapped off when it got busted off its wafer). If there is no metal can or terminals on the cap and just wires out the bottom then there has to be a negative lead if it is a multi section cap.

You need to get the schematic and trace things out if you can't make sense of the wiring that's there.

The reason I was asking about the ground connection with this capacitor is because on the bottom of the capacitor there's only 3 terminals for the "positive" leads and then theres the twist-loc tabs that held the capacitor to the phenolic wafer that snapped off the TV chassis and one of the twist-loc tabs has some wires attached to it but I'm unsure as to whether they are ground wires or if they are just using it as a convenient terminal strip.

Like I said the Capacitor is a cardboard cased multi-section capacitor with no apparent ground connection of any sort, at least not to the chassis anyways that I can see of.

As you will see from the pictures that I took of this can cap, it has absolutely no mention on the case of having a ground of any sort, and you can even see the wiring on the capacitor that there is abolutely no ground connection on this capacitor, and that the one twist-loc tab is just being used as a terminal strip and that's it, nothing ground related.

The one twist lock tab with wires on it is the common (negative) terminal of all three 40 mfd capacitors in the can. The design of this power supply calls for the this cap to be connected to a point other than ground. It might be a way for the power supply to generate a negative bias power supply. If you could get a schematic, it would be obvious.

95%of the time that a can is covered in cardboard and mounted to phenolic it's can negative terminals are NOT connected to ground but instead tie to a floating negative line at a different potential than the chassis. The can is not a tie point but the negative of the caps and the wires connected to the can are a negative rail.


One other use for the wafer and separate negative from chassis: in some series string sets the chassis is not used as a ground/B- and serves only as a shield with it's only connection to the rest of the circuit being a parallel cap and resistor to couple it to signal ground, but limit chassis shock current.

The one twist lock tab with wires on it is the common (negative) terminal of all three 40 mfd capacitors in the can. The design of this power supply calls for the this cap to be connected to a point other than ground. It might be a way for the power supply to generate a negative bias power supply. If you could get a schematic, it would be obvious.

I do have a schematic but it's hard to make heads or tails of it as far as finding the Power Supply or what not.

You know, SAMS Standard Notation might be one of the best things that ever happened for the television service industry.

I do have a schematic but it's hard to make heads or tails of it as far as finding the Power Supply or what not.

If there is a power transformer, look for it. If there is a power rectifier look for it. Even the wackiest non- standard schematics and circuit designs can be followed if you find the recognizable stuff and trace from it to what you need. If parts values are only listed in a separate table print the table and have it next to the schematic. If the schematic is on multiple pages print it out and stick the sections together into a single page.

Photofact set 110, folder 9 covers 14 Meck models from 1950...I suspect that the power supply in question is very similar to the one shown in that folder:

https://live.staticflickr.com/65535/48602290221_44121615e6_z_d.jpg

The common (connections to the can) of C1 (40,40,40) is floated from chassis ground so that a minus 3 volt supply can be created to provid bias to the video detector stage.

jr

Photofact set 110, folder 9 covers 14 Meck models from 1950...I suspect that the power supply in question is very similar to the one shown in that folder:

https://live.staticflickr.com/65535/48602290221_44121615e6_z_d.jpg

The common (connections to the can) of C1 (40,40,40) is floated from chassis ground so that a minus 3 volt supply can be created to provid bias to the video detector stage.

jr

Yes I found the power supply stage after looking over the schematic from Beitman's that I have (unfortunately I do not have access to the Sam's folder for this TV, I have every Sam's Folder from this time period except 110, and I don't wish to pay the $30 that Sam's is asking at their website for this Photofact folder copy.)

It does seem that it does have a floating ground which I'm not sure how it would work to do that with a terminal strip and 3 47 MFD 450 VDC electrolytic caps when the only terminal strips I have have the mounting tabs that mount it to the chassis also doubling as chassis ground terminals, which I don't need in this case.

It does seem that it does have a floating ground which I'm not sure how it would work to do that with a terminal strip and 3 47 MFD 450 VDC electrolytic caps when the only terminal strips I have have the mounting tabs that mount it to the chassis also doubling as chassis ground terminals, which I don't need in this case.
Don't let the lack of a proper terminal strip prevent you from doing the job right.
http://www.radiodaze.com/terminal-strips/

Don't let the lack of a proper terminal strip prevent you from doing the job right.
http://www.radiodaze.com/terminal-strips/

Thanks for the link, I think I found a terminal strip there that will work for what I need.

If the can wafer wasn't busted, and you had a 75W soldering iron I'd have suggested using the terminal strip you have and soldering the mount tab of the strip to the negative terminal lug of the can(instead of bolting it to chassis)....I do this sometimes and as long as you have a big iron and make a solid solder joint it works pretty nice. Some might complain it is not original workmanship but as long as it isn't a high buck set stuff like this doesn't make much difference.

If the can wafer wasn't busted, and you had a 75W soldering iron I'd have suggested using the terminal strip you have and soldering the mount tab of the strip to the negative terminal lug of the can(instead of bolting it to chassis)....I do this sometimes and as long as you have a big iron and make a solid solder joint it works pretty nice. Some might complain it is not original workmanship but as long as it isn't a high buck set stuff like this doesn't make much difference.

I think I will just completely remove the old can capacitor completely out of the TV and just bolt a proper terminal strip down onto the chassis and just wire it up and go from there. Since the original filter cap was a 40/40/40 @ 450 VDC capacitor I don't think it will matter where I hook up the positive leads.

OK So as luck would have it the tube socket for my Video Amp circuit on my TV is got a couple of damaged pins and I need a new tube socket, its an octal tube socket that mounts from below.

it looks like the one pictured in the link below.

https://www.tubesandmore.com/products/socket-8-pin-1-chassis-hole-1-14-mounting-centers

It also seems that I'll need a new 6AC7 tube as well for the Video Amp on my TV as one of the pins on the tube is broken.

OK So as luck would have it the tube socket for my Video Amp circuit on my TV is got a couple of damaged pins and I need a new tube socket, its an octal tube socket that mounts from below.

it looks like the one pictured in the link below.

https://www.tubesandmore.com/products/socket-8-pin-1-chassis-hole-1-14-mounting-centers

It also seems that I'll need a new 6AC7 tube as well for the Video Amp on my TV as one of the pins on the tube is broken.

If the original socket is one of those molded bakelite jobs, try to find a scrap chassis with the same kind of socket and steal the contacts from it. It's easy enough to do. The only ones you cant repair is the flat phenolic wafer type.

If the original socket is one of those molded bakelite jobs, try to find a scrap chassis with the same kind of socket and steal the contacts from it. It's easy enough to do. The only ones you cant repair is the flat phenolic wafer type.

+1 Saves a lot of effort doing it that way. Takes a bit of skill to get the donor contact out intact especially if it was soldered, but still much easier than a socket swap.

Well a bit of bad news I replaced the power supply caps and went to test my work and the 5U4G Rectifier tube is still arcing so it looks like it wasn't the power supply caps that was responsible for the arcing rectifier tube after all (actually I tested the original power supply caps after I removed them out of the circuit and they tested fine yet, they weren't shorted or anything.)

Any other ideas as to what could cause the Low Voltage rectifier tube to arc?

If you are sure that there is no extra load on the B+ (read, miss wire, leaky-shorted electrolytic capacitor) the 5U4 can be suspect too.

If you are sure that there is no extra load on the B+ (read, miss wire, leaky-shorted electrolytic capacitor) the 5U4 can be suspect too.

I've replaced all the electrolytics in the Power Supply chain, including the 20/10/10 @450 electrolytic can that's over by the high voltage cage area. And I've even tried 6 different 5U4 tubes and they all arc inside, and they all were new old stock 5U4 tubes or used ones that tested good yet.

Not sure what else to look for.

Double check that your replacement electrolytic caps are polarized correctly, if one is reversed it can fail and act like a dead short. Also look for any unusually low resistance reading from B+ to chassis ground. Check that both leads of the focus coil are not shorted to chassis ground. What value fuse is in the holder on the rear chassis? One would expect that fuse to go open if B+ is pulling excess current. You mentioned you don't have Sams 110, by any chance do you have Sams 101, folder 5?

Double check that your replacement electrolytic caps are polarized correctly, if one is reversed it can fail and act like a dead short. Also look for any unusually low resistance reading from B+ to chassis ground. Check that both leads of the focus coil are not shorted to chassis ground. What value fuse is in the holder on the rear chassis? One would expect that fuse to go open if B+ is pulling excess current. You mentioned you don't have Sams 110, by any chance do you have Sams 101, folder 5?

When I replaced the Power Supply caps I hooked the positive leads up to their own terminals and the negative leads up to the same terminal which I then bridged over to another empty terminal next to it so I had plenty of room for all of the wires, resistors and the electrolytic capacitor negative lead that all connected to the negative lead of the Power Supply cap.

As for the fuse size I checked the fuse that was in there and it was the correct size fuse.

As for the Sam's, I believe i do have 101 folder 5 in my stash, I'll double check when I get home, as I'm currently at my parent's house for the day.

I've worked on a couple of vintage B & W tv before and this is the first one I've had any major problems with before.

Double check that your replacement electrolytic caps are polarized correctly, if one is reversed it can fail and act like a dead short. Also look for any unusually low resistance reading from B+ to chassis ground. Check that both leads of the focus coil are not shorted to chassis ground. What value fuse is in the holder on the rear chassis? One would expect that fuse to go open if B+ is pulling excess current. You mentioned you don't have Sams 110, by any chance do you have Sams 101, folder 5?

OK so a little update, I was able to get the broken terminals in the video amp tube socket replaced with some terminals from a parts tube socket from a junk single tube suitcase record player, and I powered it up and the 5U4G tube is still arcing even with all of the power supply caps replaced.

Although I did think of something that could be causing my issues still,
there is an oddball dry electrolyitic capacitor in the power supply that I didn't bother replacing because it was a Dry Electrolytic and usually with my experience those Dry Electrolytics rarely fail.

Plus its an oddball value that I've never seen before, not even in modern TV sets, its a 500 MFD 5 VDC Dry Electrolytic Capacitor that is tied into the power supply chain, and maybe in this case that Dry Electrolytic did short out and that's whats causing my Rectifier tube to arc inside.

Does that sound like it could be a possibility?

Possible but highly unlikely.

To troubleshoot this (and I have had to troubleshoot similar issues before) disconnect the B+ rail and filter cap connection to your the 5U4 (remove all load from it). If it stops arcing you have confirmed the B+ rail has a short or severe overload. If it continues to arc with no load then the socket may have a short or the transformer may be supplying too high an AC voltage.

Assuming the arcing stopped reconnect the first filter cap then reconnect small parts of the B+ 1 at a time (not all at once) the first one to cause arcing is your short, and you'll have to pick it over with a fine tooth comb to find the root cause.

I've fought a few B+ shorts. Sometimes they are obvious if you look everywhere, sometimes they are hidden... Case in point: a 40s zenith chassis with only a couple rubber wires in seemingly good shape...the single rubber wire feeding the eye tube had one dry patch of insulation that had disintegrated right at the eyelet where it passed through the chassis, and was invisibly shorting to chassis there... just because you can't see a problem, and have replaced the likely suspects doesn't mean the problem isn't there.

All the electrolytic caps should be replaced, dry or not. Over time the dielectric breaks down just like the paper caps do. That 500 mfd cap can be replaced with a 470 mfd. Voltage rating can be higher, say a modern 25v shouldn't be much bigger than the original.

Possible but highly unlikely.

To troubleshoot this (and I have had to troubleshoot similar issues before) disconnect the B+ rail and filter cap connection to your the 5U4 (remove all load from it). If it stops arcing you have confirmed the B+ rail has a short or severe overload. If it continues to arc with no load then the socket may have a short or the transformer may be supplying too high an AC voltage.

Assuming the arcing stopped reconnect the first filter cap then reconnect small parts of the B+ 1 at a time (not all at once) the first one to cause arcing is your short, and you'll have to pick it over with a fine tooth comb to find the root cause.

I've fought a few B+ shorts. Sometimes they are obvious if you look everywhere, sometimes they are hidden... Case in point: a 40s zenith chassis with only a couple rubber wires in seemingly good shape...the single rubber wire feeding the eye tube had one dry patch of insulation that had disintegrated right at the eyelet where it passed through the chassis, and was invisibly shorting to chassis there... just because you can't see a problem, and have replaced the likely suspects doesn't mean the problem isn't there.

Well I'm actually wondering if that 500MFD 5 VDC capacitor is the problem because I looked at the Sam's and it says that the 500 MFD 5 VDC capacitor is the Bias Filter Capacitor, which if that's working right it may very well cause my rectifier tube arcing issue.

As for the B+ Voltage Rail and where it connects to the rectifier tube and how to test it where is that point on the Rectifier tube socket?

All the electrolytic caps should be replaced, dry or not. Over time the dielectric breaks down just like the paper caps do. That 500 mfd cap can be replaced with a 470 mfd. Voltage rating can be higher, say a modern 25v shouldn't be much bigger than the original.

I checked the Sam's for this TV and I Figured out that the 500 MFD 5 VDC Capacitor is the Bias Filter Capacitor, so it seems that if that capacitor has indeed failed like I am suspecting that it did, then it could very well be the source of my 5U4G's Arcing problems.

Would a 470 MFD 6.3 VDC electrolytic cap work as a replacement for this capacitor?

Also there's a 100 MFD 150 VDC capacitor that was a replacement at some point for C7 which was a 100 MFD 25 VDC electrolytic capacitor that must of failed at some point in time.
The strange thing is that when they hooked up the negative lead on that capacitor instead of using using the floating ground rail on one of the tube sockets or something they hooked the negative lead of that electrolytic to the chassis, which might also be causing some of my issues, C7 by the way according to the Sam's is the Vertical Output Tube Cathode Bypass Capacitor.

a 6.3V cap is a fine sub for the 5V.

The B+ connection point will be one of the 5U4 heater pins...Without the schematic in front of me, I can't tell you which, but it shouldn't be hard to figure out.

Replacing the 500mf@5V cap won't fix your problem, guaranteed. It's already got a very low resistance across it, probably 10 - 20 ohms or so (wish we could see the actual schematic). So even if the cap were dead shorted, the increased load on the power supply will be negligible.

Agree the source of your excessive current draw is not the 500 mfd cap, but it needs to go none the less. Since you apparently have the Sams folder now, how about checking out the resistance readings chart on page 8. For starters check the resistance from the 5U4 filament pins(2,8) to chassis ground. Chart says there should be approximately 22,000 ohms there.

Looking at the schematic in msg #41, it looks like the voltage on the +370 line would vary according to the setting of the focus control. Also, it looks like the +360 line might vary some as well. Am I missing something here?

Looking at the schematic in msg #41, it looks like the voltage on the +370 line would vary according to the setting of the focus control. Also, it looks like the +360 line might vary some as well. Am I missing something here?

It will change, but considering the focus control is in parallel with the 250 ohm focus coil it's overall effect is negligible. Sams will often say to the set the control to one extreme when taking voltage or resistance measurements.

Thanks. That makes sense. I'll be on the lookout for the SAMS note.

OK so question, How do I go about measuring the B+ Voltage (the voltages on the 5U4G Tube) with the tube in place arcing while the TV is powered up? Wouldn't running the TV that long with the 5U4G tube arcing like that ruin that tube?

Don’t power it up again to check voltage! There is likely a short to ground that you must identify and remedy first. Do some ohm meter tests first.

Agree the source of your excessive current draw is not the 500 mfd cap, but it needs to go none the less. Since you apparently have the Sams folder now, how about checking out the resistance readings chart on page 8. For starters check the resistance from the 5U4 filament pins(2,8) to chassis ground. Chart says there should be approximately 22,000 ohms there.

jr

Don’t power it up again to check voltage! There is likely a short to ground that you must identify and remedy first. Do some ohm meter tests first.



jr


OK So testing pins 2 and 8 of the 5U4G tube socket I'm only getting 25.5 Ohms on those pins, and not the 22,000 Ohms I should be getting.

I'm guessing that means that the issues I'm having with the excessive (4.5 Amps, 520 Watts) current draw lies there somewhere?

Or is that a sign that something else further down the line is causing that excessively low filament resistance reading on my 5U4G tube socket?

This TV has me seriously stumped, there is NOTHING in this TV that looks like it could of shorted to ground.
The 26.0 Ohm Reading I'm getting on the 5U4G rectifier tube Socket rather than the 22,000 Ohm reading I should be getting is leading me to think that perhaps my 5v winding in my power transformer had failed in some way shape or form.

Everything else measures fine and there isnt' anything else in the TV that I can see that looks to be bad, all of the resistors test within tolerance (which is surprising) and leaky capacitors wouldn't cause excessive amounts of current draw to the point that the unit is drawing 3x the current its rated for.

It can't be the power supply caps because I had already replaced those with brand new ones and was careful to observe proper polarity and its still drawing over 4 amps of current and over 500 watts of power and the 5U4G tube is still arcing so like I said this TV has me stumped I cannot for the life of me figure out whats going on with this TV. :sigh: :tears:

OK So testing pins 2 and 8 of the 5U4G tube socket I'm only getting 25.5 Ohms on those pins, and not the 22,000 Ohms I should be getting.

I'm guessing that means that the issues I'm having with the excessive (4.5 Amps, 520 Watts) current draw lies there somewhere?

Or is that a sign that something else further down the line is causing that excessively low filament resistance reading on my 5U4G tube socket?

Are you measuring 2 to ground and 8 to ground, or measuring 2 to 8 ( 2 to 8 ain't helpful)?

Either 2 or 8 should have a choke(in series with B+) or B+ line connected to it... unsolder the B+ line or choke and check 2 and or 8 to ground resistance. If the resistance is much higher than before then you have confirmed the rect and transformer are good. You'll then have to disconnect splits on the B+ line from the main line and check b+ to ground resistance till you find the point that has the short.

Most B+ shorts happen in ways that make visually identifying the issue impossible. You gotta rely on instruments, logic guided by the schematic.

It is not impossible for paper caps to dead short and for that to effect the B+... usually there is a power resistor in series that smokes out first, but not all sets are wired the same.

If I had it on my bench I could probably isolate the short in 30 min.

...If I had it on my bench I could probably isolate the short in 30 min.
I could do in less than 1 min. Just kidding! Make it 2 minutes tops. :D

Are you measuring 2 to ground and 8 to ground, or measuring 2 to 8 ( 2 to 8 ain't helpful)?

Either 2 or 8 should have a choke(in series with B+) or B+ line connected to it... unsolder the B+ line or choke and check 2 and or 8 to ground resistance. If the resistance is much higher than before then you have confirmed the rect and transformer are good. You'll then have to disconnect splits on the B+ line from the main line and check b+ to ground resistance till you find the point that has the short.

Most B+ shorts happen in ways that make visually identifying the issue impossible. You gotta rely on instruments, logic guided by the schematic.

It is not impossible for paper caps to dead short and for that to effect the B+... usually there is a power resistor in series that smokes out first, but not all sets are wired the same.

If I had it on my bench I could probably isolate the short in 30 min.

I was measuring pin two to ground and pin 8 to ground, and those were the measurements I got, 26 ohms on pin 2 measuring to ground and pin 8 measuring to ground.

And as far as a paper cap being responsible for this goes, there are over 50 capacitors in there I'll have to check individually which will take me a while to test each and every capacitor with an ohm meter to see if the capacitor is still "good" or if it's open.

I was measuring pin two to ground and pin 8 to ground, and those were the measurements I got, 26 ohms on pin 2 measuring to ground and pin 8 measuring to ground.

And as far as a paper cap being responsible for this goes, there are over 50 capacitors in there I'll have to check individually which will take me a while to test each and every capacitor with an ohm meter to see if the capacitor is still "good" or if it's open.

If you are testing capacitance, don't bother. If the cap is open that is better. What you want to do do if you are hell bent on checking the paper caps is check the resistance across the cap and make sure it is too high for the meter to measure, and even that is a waste of time for two reasons. 1 some caps won't show leakage at the low 9V a DMM puts out (though that 25 ohms is registering on a meter so you might find it that way). 2 there is no guarantee it is a capacitor (could be almost anything on the B+ line) and it is far simpler (less, possibly MUCH less than half the work of checking all the caps) to start at the rectifier and split the B+circuit into segments by cutting it at nodes then measuring resistance to ground and splitting the lowest resistance section into smaller parts till you find the short.
Can you post a schematic of the power supply in your set?... I can write you a simple procedure to isolate the short if I can see the circuit.

I was measuring pin two to ground and pin 8 to ground, and those were the measurements I got, 26 ohms on pin 2 measuring to ground and pin 8 measuring to ground.

And as far as a paper cap being responsible for this goes, there are over 50 capacitors in there I'll have to check individually which will take me a while to test each and every capacitor with an ohm meter to see if the capacitor is still "good" or if it's open.

Disconnect the lead going to the 5U4 socket from the B+ circuitry. It has to be in the B+ feeds, electrolytics, grounded filter choke, even the vertical output transformer.
As stated before, the smaller circuit capacitors throughout the circuitry of the set wouldn't cause a dead short in the B+ rail.
IIRC, the B- isn't going to the chassis but is forming a low bias source. :scratch2:

With how many times now the poor 5U4 has been the purple guy here :whip:

it stands to reason that when the short circuit is finally found and fixed that the 5U4 may be too far gone to properly run the set .

Disconnect the lead going to the 5U4 socket from the B+ circuitry. It has to be in the B+ feeds, electrolytics, grounded filter choke, even the vertical output transformer.
As stated before, the smaller circuit capacitors throughout the circuitry of the set wouldn't cause a dead short in the B+ rail.
IIRC, the B- isn't going to the chassis but is forming a low bias source. :scratch2:

I would also disconnect the focus coil and measure the resistance to ground of both leads. Also do the same for the 5U4 5 volt heater winding of the power transformer.

jr

With how many times now the poor 5U4 has been the purple guy here :whip:

it stands to reason that when the short circuit is finally found and fixed that the 5U4 may be too far gone to properly run the set .

Don't worry I have several 5U4s to work with, the one I'm using right now is one that wasn't in very good shape to begin with, I haven't been using the original one.

If you are testing capacitance, don't bother. If the cap is open that is better. What you want to do do if you are hell bent on checking the paper caps is check the resistance across the cap and make sure it is too high for the meter to measure, and even that is a waste of time for two reasons. 1 some caps won't show leakage at the low 9V a DMM puts out (though that 25 ohms is registering on a meter so you might find it that way). 2 there is no guarantee it is a capacitor (could be almost anything on the B+ line) and it is far simpler (less, possibly MUCH less than half the work of checking all the caps) to start at the rectifier and split the B+circuit into segments by cutting it at nodes then measuring resistance to ground and splitting the lowest resistance section into smaller parts till you find the short.
Can you post a schematic of the power supply in your set?... I can write you a simple procedure to isolate the short if I can see the circuit.

I've got a schematic for the power supply circuit, I'll upload it when I get a chance.

Yes, looking forward to seeing a schematic!
I would disconnect all connection off the 5U4 that were suppling and voltages and see if it was arcing after that.
Beyond that I would avoid any more power ups with that much load put on the transformer otherwise it's going to cook out a winding in short order, if that is not already a issue.
Look for defective 5U4 tube socket, also a filter choke with a short to chassis. I can't imagine the 5 volt cap would not cause that much of a problem.
As someone else mention the focus, check that the focus control is not shorting to chassis.
What is the current draw on the input of the transformer with all the tubes out?

Posted below for everyone's information is the power supply section of the Schematic for this TV.

Hope this helps everyone help me figure out why my TV's power supply is drawing over 8 Amps of current and causing my 5U4 tube to arc and nearly redplate.

Disclaimer: the component designators in the attachment are fuzzy and I may not have read them correctly.

Procedure: disconnect C1a positive and L1 from pin 2 of 5U4. Measure resistance to ground at pin 2 if the resistance is that specified in the service literature or higher then the shot is not in the tube or power transformer (but if it meaures well below spec resistance spec the tube socket and or power transformer are prime suspects).

If you cleared the power transformer of suspicion next disconnect L1, R95, C2b, focus control, and focus coil from each other. Check resistance of C1a, C1b, and both wires of L1 to ground...if any of them measures less than 1M to ground replace the part that has low resistance.

Check R95, focus pot, and focus coil to ground. If R95 checks lower than 100k to ground you may need to check the circus it feeds off the image you attached. If focus coil checks under 100k to ground unhook the other focus coil lead and measure each lead to ground if still low replace focus coil. If focus pot tests under 100k to ground disconnect it's terminals from circuit and measure from each to ground. If still too low pot is defective.
Also disconnect the positive of C1c and measure it's resistance to ground. Do the same for R94...if you still haven't found the short check the items off the attached image that the B+ drives.

Methodically divide and conquer...er um I mean measure till you find your shorted part(s). Replace culprit part(s) remeasure, reconnect all disconnected connections, remeasure to be sure the short is gone, and then power up if all now checks good (use a variac and or dim bulb tester if you have one just in case something is still wrong).

Disclaimer: the component designators in the attachment are fuzzy and I may not have read them correctly.

Procedure: disconnect C1a positive and L1 from pin 2 of 5U4. Measure resistance to ground at pin 2 if the resistance is that specified in the service literature or higher then the shot is not in the tube or power transformer (but if it meaures well below spec resistance spec the tube socket and or power transformer are prime suspects).

If you cleared the power transformer of suspicion next disconnect L1, R95, C2b, focus control, and focus coil from each other. Check resistance of C1a, C1b, and both wires of L1 to ground...if any of them measures less than 1M to ground replace the part that has low resistance.

Check R95, focus pot, and focus coil to ground. If R95 checks lower than 100k to ground you may need to check the circus it feeds off the image you attached. If focus coil checks under 100k to ground unhook the other focus coil lead and measure each lead to ground if still low replace focus coil. If focus pot tests under 100k to ground disconnect it's terminals from circuit and measure from each to ground. If still too low pot is defective.
Also disconnect the positive of C1c and measure it's resistance to ground. Do the same for R94...if you still haven't found the short check the items off the attached image that the B+ drives.

Methodically divide and conquer...er um I mean measure till you find your shorted part(s). Replace culprit part(s) remeasure, reconnect all disconnected connections, remeasure to be sure the short is gone, and then power up if all now checks good (use a variac and or dim bulb tester if you have one just in case something is still wrong).

Sorry about the fuzzy diagram the Sam's Folder came to me that way when I downloaded it from the Sam's website.

I'll definitely check those things out for sure.

I'll definitely check those things out for sure.

But by all means start with this from Electronic M:


Procedure: disconnect C1a positive and L1 from pin 2 of 5U4. Measure resistance to ground at pin 2 if the resistance is that specified in the service literature or higher then the shot is not in the tube or power transformer (but if it meaures well below spec resistance spec the tube socket and or power transformer are prime suspects).

With C1a+ and L1 disconnected from pin 2, you should read infinite resistance (open circuit) from pin 2 to ground. If so, that eliminates 5U4 socket and xfmr as suspects. Then proceed 'downstream' per Electronic M's directions.

I would also disconnect the focus coil and measure the resistance to ground of both leads. Also do the same for the 5U4 5 volt heater winding of the power transformer.

jr

I forgot about the focus coil circuit!
The last three sets I restored had PM focus units or electrostatic focusing. :scratch2:

Wow there are more posts about this set than there are Parts in it LOL

Wow there are more posts about this set than there are Parts in it LOL

Whomever said it was easy to teach troubleshooting skills via the internet was mistaken. ;)

Whomever said it was easy to teach troubleshooting skills via the internet was mistaken. ;)

Yeah, I wish there was someone nearby that could help me with this but unfortunately none of you here live nearby where I live.

I really do want to get this set going because it is such a rare set and also this would be the oldest tv I've ever owned.

Vortalexfan, how are you doing with this, are you making any headway?

Vortalexfan, how are you doing with this, are you making any headway?

Unfortunately no, I'm no closer to figuring out what's causing my 5U4 tube to arc and red plate than I was a couple of weeks ago.

I've been testing various components and replacing suspect capacitors in the power supply and I'm not getting anywhere.

Unfortunately no, I'm no closer to figuring out what's causing my 5U4 tube to arc and red plate than I was a couple of weeks ago.

I've been testing various components and replacing suspect capacitors in the power supply and I'm not getting anywhere.

So what did you find out when you followed Electronic M's below procedure?


Procedure: disconnect C1a positive and L1 from pin 2 of 5U4. Measure resistance to ground at pin 2 if the resistance is that specified in the service literature or higher then the short is not in the tube or power transformer (but if it meaures well below spec resistance spec the tube socket and or power transformer are prime suspects).

So what did you find out when you followed Electronic M's below procedure?

I haven't had a chance to try it yet.

I'm actually kind of afraid to disconnect the wires from the rectifier tube socket because I'm afraid I might accidentally reconnect them wrong and screw things up even more than they already are, especially since I don't which wires are the wires that Electronic M is talking about.

I did post a schematic of the power supply for this TV on here, if someone could mark on the power supply which wires are the ones I need to disconnect and test I can get a better idea of which wires to disconnect and test without risking disconnecting more wires than need to be.

I haven't had a chance to try it yet.

I'm actually kind of afraid to disconnect the wires from the rectifier tube socket because I'm afraid I might accidentally reconnect them wrong and screw things up even more than they already are, especially since I don't which wires are the wires that Electronic M is talking about.

I did post a schematic of the power supply for this TV on here, if someone could mark on the power supply which wires are the ones I need to disconnect and test I can get a better idea of which wires to disconnect and test without risking disconnecting more wires than need to be.

Can you take a picture before you disconnect the wires so you'll have a reference to get them back to original? Not trying to be rude, but you need to take the initiative to follow directions and report back if you expect folks to help you troubleshoot this. If I can get the picture to load I drew a red line thought the connections you'll need to open.

https://live.staticflickr.com/65535/48834794583_5fa4826e45_z.jpg

Can you take a picture before you disconnect the wires so you'll have a reference to get them back to original? Not trying to be rude, but you need to take the initiative to follow directions and report back if you expect folks to help you troubleshoot this. If I can get the picture to load I drew a red line thought the connections you'll need to open.

https://live.staticflickr.com/65535/48834794583_5fa4826e45_z.jpg

That's the thing that L1 coil doesn't seem to be present in my TV, the Focus coil is there but that inductor coil or whatever it is that L1 is supposed to be doesn't seem to be present in my TV, at least not that I can see of.

I'll take a picture of that part of the TV so you can see what I mean.

Below is a picture of the power supply circuit on my TV showing that L1 does NOT exist in my set (at least not that I'm aware of).

Below is a picture of the power supply circuit on my TV showing that L1 does NOT exist in my set (at least not that I'm aware of).

L1 is the small transformer(filter choke) to the left of the power transformer in your photo. Right above those electrolytic caps you've replaced. I can read the part number LG-10021 in your picture. There's only 2 wires exiting from it. One of the wires should go over to pin 2 of the 5U4 socket. It's also shown on page 4 in sams set 101, folder 5.

All you should need to do is remove the one small white wire from pin 2 of the 5U4 socket. If you follow that white wire over to your terminal strip it should connect to the plus end of one of the electrolytic caps and also to one of the black wires that goes to L1. It's possible you have a wiring error on your terminal strip, but for starters remove the white wire from pin 2 and see if that fixes the excessive current draw problem. Looking at your picture it seems to me that you have that white wire from pin 2 going to the negative side of that cap?

https://live.staticflickr.com/65535/48835559852_bd00e02f87_z.jpg

All you should need to do is remove the one small white wire from pin 2 of the 5U4 socket. If you follow that white wire over to your terminal strip is should connect to the plus end of one of the electrolytic caps and also to one of the black wires that goes to L1. It's possible you have a wiring error on your terminal strip, but for starters remove the white wire from pin 2 and see if that fixes the excessive current draw problem. Looking at your picture it seems to me that you have that white wire from pin 2 going to the negative side of that cap?

https://live.staticflickr.com/65535/48835559852_bd00e02f87_z.jpg

now wait, L1 is the Focus Coil, which doesn't make any sense because L1 and the Focus Coil are marked as two separate items on the schematic...:scratch2:

now wait, L1 is the Focus Coil, which doesn't make any sense because L1 and the Focus Coil are marked as two separate items on the schematic...:scratch2:

Nope. T6 is the focus coil and it's mounted on the neck of the Picture tube. L1 is the small transformer(choke) mounted under the chassis as I have it marked.

Dude, take a deep breath and just clip the wire goin' to pin 2.

Now, measure from pin 2 to ground. If infinite resistance (open circuit), tube socket and power xfmr are not suspect. Short is 'downstream'.

Dude, take a deep breath and just clip the wire goin' to pin 2.

Now, measure from pin 2 to ground. If infinite resistance (open circuit), tube socket and power xfmr are not suspect. Short is 'downstream'.

I unsoldered the wire and then tested pin 2 and it measured infinite like it should.

So where should I check next?

How many ohms is there between the ground and the white wire you unsoldered?

How many ohms is there between the ground and the white wire you unsoldered?

There is 256.6 Ohms between ground and the white wire that I unsoldered from pin 2 of the 5U4 tube socket.

There is 256.6 Ohms between ground and the white wire that I unsoldered from pin 2 of the 5U4 tube socket.

Is that white wire connected to the same point as the negative side of C1A & B as it appears in your picture? If so it needs to be moved to the plus end of C1A. Also check to see if R93 is in fact still 15 ohms.

That seems quite low, some of that could be the electrolytics loading the circuit down as they charge. To me it looks like its ahead of the transformer and rectifier.
You could power it up and watch the rectifier tube for arcing, and red plating.

Is that white wire connected to the same point as the negative side of C1A & B as it appears in your picture? If so it needs to be moved to the plus end of C1A. Also check to see if R93 is in fact still 15 ohms.

It was but then I switched it around once I realized it was hooked up wrong.

I powered it up with that white wire disconnected from the 5U4 tube and it didn't arc anymore.

I'm guessing that means that the Filter Choke may be bad? How hard is it to replace those and how expensive are they to buy? Also how necessary is it to have that filter choke in the circuit? Can the set be ran without it in circuit?

That seems quite low, some of that could be the electrolytics loading the circuit down as they charge. To me it looks like its ahead of the transformer and rectifier.
You could power it up and watch the rectifier tube for arcing, and red plating.

without that white wire attached to the 5U4 tube socket the tube doesn't arc anymore which I'm guessing means that the filter choke is bad.

without that white wire attached to the 5U4 tube socket the tube doesn't arc anymore which I'm guessing means that the filter choke is bad.

All it means is that the power transformer and tube, and tube socket are good (and that the short is inor down stream of L1). You need to confirm L1 is bad by unhooking both leads on the choke and measure resistance of both to ground and confirm it is a measurable/low resistance to confirm L1 is bad. If L1 is infinite resistance to ground then it is good and you still need to find the actual short.

Gotta keep dividing and conquering... you've cleared some of the more important parts, and found a a direction to follow to find the short. Keep at it.
Don't let yourself get lazy or confused.

All it means is that the power transformer and tube, and tube socket are good (and that the short is inor down stream of L1). You need to confirm L1 is bad by unhooking both leads on the choke and measure resistance of both to ground and confirm it is a measurable/low resistance to confirm L1 is bad. If L1 is infinite resistance to ground then it is good and you still need to find the actual short.

Gotta keep dividing and conquering... you've cleared some of the more important parts, and found a a direction to follow to find the short. Keep at it.
Don't let yourself get lazy or confused.

Ok. Just curious but can a filter choke be wired up backwards, or does it not matter which way it's wired up?

It was but then I switched it around once I realized it was hooked up wrong.

OK, so you switched it around. Have you powered up the set with the white wire connected back to pin 2 of the 5U4 since you switched it? If you previously had that white wire going to the negative side of the C1A, & B caps, that alone explains why the set was drawing excessive current, because that point connects to the center tap of the high voltage windings. Normally there would be 15 ohms from that point to chassis ground, which is why I suggested you also measure the resistance of R93(should be 15 ohms)

I powered it up with that white wire disconnected from the 5U4 tube and it didn't arc anymore.

I'm guessing that means that the Filter Choke may be bad? How hard is it to replace those and how expensive are they to buy? Also how necessary is it to have that filter choke in the circuit? Can the set be ran without it in circuit?

Don't worry about replacing the choke until you know it's bad.
Heres how to test it.

There' a black wire that is connected to the filter choke that leads to the lower end of the terminal strip where the electrlyics are connected.
I can't see the other wire that come from the choke, but it too should be at the terminal strip. Mark these so that you can connect them back in the same places.
Unsolder these wires and and see if you can get any resistance between it and the chassis.
The reading with both wires off the choke should be infinity or at least in the several megohm range between the chassis and one of the choke leads
The reading between the 2 leads off the choke should be low. Somewhere around 3 to 20 ohms for example.

OK, so you switched it around. Have you powered up the set with the white wire connected back to pin 2 of the 5U4 since you switched it? If you previously had that white wire going to the negative side of the C1A, & B caps, that alone explains why the set was drawing excessive current, because that point connects to the center tap of the high voltage windings.

I did try it out with the wires switched and it still arced, but not nearly as bad as it did and the tube wasn't trying to red plate either like it was before I switched the wires.
Basically its doing the same thing it did before I replaced the power supply caps.

Don't worry about replacing the choke until you know it's bad.
Heres how to test it.

There' a black wire that is connected to the filter choke that leads to the lower end of the terminal strip where the electrlyics are connected.
I can't see the other wire that come from the choke, but it too should be at the terminal strip. Mark these so that you can connect them back in the same places.
Unsolder these wires and and see if you can get any resistance between it and the chassis.
The reading with both wires off the choke should be infinity or at least in the several megohm range between the chassis and one of the choke leads
The reading between the 2 leads off the choke should be low. Somewhere around 3 to 20 ohms for example.

OK thanks, I was just getting ready to do that.

I did try it out with the wires switched and it still arced, but not nearly as bad as it did and the tube wasn't trying to red plate either like it was before I switched the wires.
Basically its doing the same thing it did before I replaced the power supply caps. Then by all means do as Electronic M suggested and check resistance from each lead of L1 to chassis ground. You may need to disconnect both L1 wires from the circuit to get an accurate reading.(as Tube TV said above my post)

Then by all means do as Electronic M suggested and check resistance from each lead of L1 to chassis ground. You may need to disconnect both L1 wires from the circuit to get an accurate reading.(as Tube TV said above my post)

I checked the filter choke with my ESR/LCR Meter (which also checks resistors and resistance loads) and the filter choke checks out within tolerance of the original specs given in the Sam's Folder, it checked at 27.7 Ohms and 1.69 Henries, which the original specs given in the Sam's Folder for the Choke is 32 Ohms and 1.5 Henries.

As for the individual leads checked to ground, one lead read 254 Ohms and the other lead measured infinite.

The filter choke is definitely necessary for proper power supply operation. It’s easy to install - there are only two leads. The bigger problem would be finding a replacement.

I checked the filter choke with my ESR/LCR Meter (which also checks resistors and resistance loads) and the filter choke checks out within tolerance of the original specs given in the Sam's Folder, it checked at 27.7 Ohms and 1.69 Henries, which the original specs given in the Sam's Folder for the Choke is 32 Ohms and 1.5 Henries.

As for the individual leads checked to ground, one lead read 254 Ohms and the other lead measured infinite.

[Edit] I'm not sure how it can measure 27.7 ohms across the two leads and be infinite from one lead to ground. But it's bad none the less. ;)

Not sure how one lead could measure infinite to ground if as you say you measured 27.7 ohms between the two leads. It should show leakage from either lead to ground, one being 27.7 higher that the other. Make sense?

Well I just tried measuring the individual leads again and now both of them are measuring infinite to ground, which I'm not sure how that's possible, as you said. But of course I'm not sure if I had all that good of a connection between the multimeter probe and the wire coming out of the choke which when you have your multimeter on your workbench top and the choke wire is hanging in mid air its kind of hard to get a solid connection without using aligator clip leads, which I have but not for my multimeter.

I checked the filter choke with my ESR/LCR Meter (which also checks resistors and resistance loads) and the filter choke checks out within tolerance of the original specs given in the Sam's Folder, it checked at 27.7 Ohms and 1.69 Henries, which the original specs given in the Sam's Folder for the Choke is 32 Ohms and 1.5 Henries.

As for the individual leads checked to ground, one lead read 254 Ohms and the other lead measured infinite.

That 254 ohms from one lead to ground reading indicates a short to ground in L1 ( I assume you unsoldered L1s leads from the rest of the circuit)...........
.... however I'm suspicious of that readinds accuracy.
If you measured from 1 lead to another and got 32ohms, then measured 1 lead to ground and got 254ohms to ground then logic says the other lead should have in the neighborhood of 222 to 286 ohms to ground instead of open circuit that you measured(that or the 32 Ohms across the leads is actually open circuit)....

L1 probably is bad but I'd like you to redo all the measurements on it you just made to confirm no mistakes were made, and hopefully this time not obtain numbers that together should be impossible for this part.

Edit:I see progress was made while I was typing.
Do you you have alligator clip leads with an alligator clip on each end of the wire? If so clip one end to a probe on your meter and the other to the test point in circuit. You can do that for both meter leads to do hands free measurement. This may add as much as an ohm to a measurement, but in most tube circuit work that is too small a difference to matter.

That 254 ohms from one lead to ground reading indicates a short to ground in L1 ( I assume you unsoldered L1s leads from the rest of the circuit)...........
.... however I'm suspicious of that readinds accuracy.
If you measured from 1 lead to another and got 32ohms, then measured 1 lead to ground and got 254ohms to ground then logic says the other lead should have in the neighborhood of 222 to 286 ohms to ground instead of open circuit that you measured(that or the 32 Ohms across the leads is actually open circuit)....

L1 probably is bad but I'd like you to redo all the measurements on it you just made to confirm no mistakes were made, and hopefully this time not obtain numbers that together should be impossible for this part.

Edit:I see progress was made while I was typing.
Do you you have alligator clip leads with an alligator clip on each end of the wire? If so clip one end to a probe on your meter and the other to the test point in circuit. You can do that for both meter leads to do hands free measurement. This may add as much as an ohm to a measurement, but in most tube circuit work that is too small a difference to matter.

No I don't unfortunatly do not have double sided aligator clips.

The aligator clip leads are on my ESR/LSR Meter leads, which I did try to use as stand alone aligator clips to clip onto the filter choke lead on one end and then take the other aligator clip lead and clipped it to the multimeter probe and the banana plug end of the aligator clip lead that was attached to the filter choke lead and I was still getting an infinite reading (O. L.) on my multimeter for both choke leads, so it seems that the filter choke is bad.

Also wiggle the wires on L1 while rechecking for the short to ground to rule out a possible intermitent short . To be at infinity on one side of the choke is not possible.
The choke is simply one long run of wire on a transformer core.
Edit: also make sure that when testing one lead on L1 that the other lead is not touching the chassis or other parts in the circuit.

I looked over at Antique Electronic Supply (AES) and it seems they actually have the Filter Choke I need for the Power Supply on the TV.

The Specs given in the Sam's Folder is 1.5 Henries .200 ADC, which I'm assuming .200 A is the same as 200mA which if that's the case AES has a version of that particular Filter Choke in stock and its only $15, the only difference is that the ones AES has are rated at 56 Ohms rather than 32 Ohms like the original which I would think that wouldn't matter too much.

Also wiggle the wires on L1 while rechecking for the short to ground to rule out a possible intermitent short . To be at infinity on one side of the choke is not possible.
The choke is simply one long run of wire on a transformer core.

Its checking infinite on both wire leads, not just one of them, I rechecked my work.

Its checking infinite on both wire leads, not just one of them, I rechecked my work.

A Hammond #156R should do the trick. As far as intermittent resistance to ground, it's very possible the insulation is breaking down under presence of high voltage, then acting flaky without. If it were my set I'd probably be temporarily tacking in a large wattage 50 ohm resistor to replace the choke and continue to trouble shoot. Ideally you should be bringing up the AC voltage slowly with a variac, or at minimum a dim bulb tester while monitoring the power supply voltage. Highly unlikely your out of the woods, but it's a great start!

If if consistantly reading infinity, and 27 ohm between the leads it's fine. And the reading on the LCR meter are in spec. If it was shorted the LCR reading would be way off . So I'd say that you've ruled it out as a potential problem.

Yes, what Kevin said is dead on. There could be a insulation breakdown that shows up with the higer voltages.

A Hammond #156R should do the trick. As far as intermittent resistance to ground, it's very possible the insulation is breaking down under presence of high voltage, then acting flaky without. If it were my set I'd probably be temporarily tacking in a large wattage 50 ohm resistor to replace the choke and continue to trouble shoot. Ideally you should be bringing up the AC voltage slowly with a variac, or at minimum a dim bulb tester while monitoring the power supply voltage. Highly unlikely your out of the woods, but it's a great start!

I actually do have a variac but its currently not wired up, as it needs a box or something to be installed in and then an outlet wired up to it and a cord as well. (it was a variac that was inside a console style cabinet originally as part of a speed control on a milling machine of some sort).

If if consistantly reading infinity, and 27 ohm between the leads it's fine. And the reading on the LCR meter are in spec. If it was shorted the LCR reading would be way off . So I'd say that you've ruled it out as a potential problem.

A quick way to find out would be to resolder the input lead, but leave the output lead disconnected.

Yes, what Kevin said is dead on. There could be a insulation breakdown that shows up with the higer voltages.

That's what I was thinking as well.
I will more than likely order a new Filter Choke from AES and install that into the TV and see if that doesn't do the trick.

https://www.tubesandmore.com/products/filter-choke-hammond-open-bracket

So will the Filter Choke in the link above work, the one that's labeled 1.5 Henry and 200 mA?

A quick way to find out would be to resolder the input lead, but leave the output lead disconnected.

which one is the input lead and which one is the output lead?
I'm assuming the input lead is the one that's connected to the white wire that was coming off pin 2 of the 5U4 tube socket?

which one is the input lead and which one is the output lead?
I'm assuming the input lead is the one that's connected to the white wire that was coming off pin 2 of the 5U4 tube socket?

It will be the one that is connected to the filter cap + lead that is connected to the 5U4.

Edit: yes pin 2

I'm assuming the input lead is the one that's connected to the white wire that was coming off pin 2 of the 5U4 tube socket?

Yes the white wire that should now be connected to the plus side of C1A.

It will be the one that is connected to the filter cap + lead that is connected to the 5U4.

Edit: yes pin 2

OK so I tried what you said and also swapped out the rectifier tube with a NOS one and the tube didn't arc, so I tried hooking up the second lead and turned on, and the tv the tube still didn't arc but something smoked on the bottom of the TV right around one of the IF cans but what's weird is that none of the parts where it looked like the smoke was coming from looked toasty (unless the IF can itself was cooked), so going by that information it does seem that the Filter Choke is bad.

So will the Filter Choke in the link above work, the one that's labeled 1.5 Henry and 200 mA? Their part number P-T156R should be fine. If the mounting spacing is off you may need to drill a new hole.

so going by that information it does seem that the Filter Choke is bad.

Not necessarily, a short to ground in the choke would not cause a component down stream from it to smoke. You could have a paper power supply bypass cap that's leaky or shorted, which generally will smoke a resistor feeding voltage to that circuit. In some cases it could be a coil. Can you post a picture showing the area the smoke came from?

which one is the input lead and which one is the output lead?
I'm assuming the input lead is the one that's connected to the white wire that was coming off pin 2 of the 5U4 tube socket?

Chokes are non-polarized and there is no such thing as connecting it backwards.

Only tubes, diodes, transistors, and electrolytic capacitors are polarized.

Most likely the smoke around the IF can was caused by bad wax paper cap that's drawing excessive current. All of those wax paper caps are leaking and it they are leaking enough they will smoke, or cook something in the circuit they are connected to.
My own guess is the choke is fine, but if you are putting in a parts order it might be nice to have a spare on hand. I would be looking ahead of the the choke.

What did the smoke smell like? Burnt wax, hot bakelite ?

Not necessarily, a short to ground in the choke would not cause a component down stream from it to smoke. You could have a paper power supply bypass cap that's leaky or shorted, which generally will smoke a resistor feeding voltage to that circuit. In some cases it could be a coil. Can you post a picture showing the area the smoke came from?

See Picture below for where the magic smoke came from.

Most likely the smoke around the IF can was caused by bad wax paper cap that's drawing excessive current. All of those wax paper caps are leaking and it they are leaking enough they will smoke, or cook something in the circuit they are connected to.
My own guess is the choke is fine, but if you are putting in a parts order it might be nice to have a spare on hand. I would be looking ahead of the the choke.

What did the smoke smell like? Burnt wax, hot bakelite ?

The weird thing is that when whatever smoked smoked it didn't have any sort of burnt smell or any other smell for that matter, it was odorless.

There are some paper caps tied into the power supply on the AC side both of which are tied to ground on one end. Could those be the cause of the issues I'm having?

Could have been releasing steam more than smoke.
I doubt than one of those wax paper caps are good. And those electrolytics on the bottom right are probably leaking as well.
It would be better in a lot of ways to change all those caps as they are going to need to be done if you want any kind of reliabilty out of the tv, and furthermore they are likely to send you on a wild goose chase dignosing the probems.
I've had many sets that run ok with the old caps in place for the first 5 or 10 minutes and then everything starts to fail , the vertical starts to shrink, or the high voltage and horizontal drops or completely quits working. It's easier to change all of these and you have a fresh start and you have the caps out of the way of potential problems.
Plus it can simplify diagnosing a set because you won't have multiple issues caused by bad capacitors. This is especially important when you are new to tv's.
The last thing you want is to cook a transformer or a IF can or the flyback, as these can be the hardest parts to get ahold of .

Agree all the paper and electrolytic caps need to be replaced. Take a look at R50, it's suppose to be 1k ohm and feeds B+ to the 1st sound IF stage. C49 (.02uf)is the stages decoupling. Good chance C49 is leaking current to ground and overheated R50.



https://live.staticflickr.com/65535/48838335608_aa6592358a_z.jpg

There are some paper caps tied into the power supply on the AC side both of which are tied to ground on one end. Could those be the cause of the issues I'm having?

Not the cause of your problems. But they are subject to blowing up if not replaced with some specified for across the AC line or line to neutral, such as these. https://www.mouser.com/ProductDetail/Murata-Electronics/DE2E3SA103MN7AT02F?qs=sGAEpiMZZMu3dWSqd4Tl0G9pZNen 5IS97GxoafTCmG2Tbc5SnxDEDw%3D%3D

Agree all the paper and electrolytic caps need to be replaced. Take a look at R50, it's suppose to be 1k ohm and feeds B+ to the 1st sound IF stage. C49 (.02uf)is the stages decoupling. Good chance C49 is leaking current to ground and overheated R50.



https://live.staticflickr.com/65535/48838335608_aa6592358a_z.jpg

I would like to replace all those capacitors at once but I just recently bought a new (to me) car and I now have car payments and I was just dropped down to 2 days a week at work so now my paychecks are going to be a little bit smaller than they have been.
So I'm going to have to hold off on ordering the capacitors for right now (until I have made my first car payment and my other expenses come out which will probably only leave me with about $30 left which won't be enough to get the 20+ capacitors I need to recap this TV).
Unless someone here has some spare capacitors they could send me.

I will definitely check C49 and R50.

Ok, so a little update, I replaced the resistor and capacitor you guys mentioned were probably responsible for the smoke earlier and also a couple other capacitors nearby that I had on hand and I managed to get the tube to stop arcing and the current draw down to 3 amps from the previous 8 amps that it was drawing before.

So I think we're making some progress.:thmbsp::yes::scratch2:

3 amps is still pretty high but much better than 8. That's for sure.

So I think we're making some progress.:thmbsp::yes::scratch2:

Just out of curiosity, how many DC volts do you measure from pin 2 of the 5U4 to ground? And from pin 5 of the 6W4 to ground? Before measuring take a look at the voltage chart(page 8) in your Sams so you have an idea of what to expect.

Just out of curiosity, how many DC volts do you measure from pin 2 of the 5U4 to ground? And from pin 5 of the 6W4 to ground? Before measuring take a look at the voltage chart(page 8) in your Sams so you have an idea of what to expect.

I'm assuming the set will be powered up for this procedure?
Also will the tubes be removed for this or are they still in the sockets?

3 amps is still pretty high but much better than 8. That's for sure.

Also I did figure out why the fuse wasn't blowing from the excessive current draw, somone at some point in time replaced the original 5 amp fuse with a 10 amp automotive fuse...:scratch2::nono::thumbsdn:

I'm assuming the set will be powered up for this procedure?
Also will the tubes be removed for this or are they still in the sockets?

Yes powered on with tubes in sockets.

Also I did figure out why the fuse wasn't blowing from the excessive current draw, somone at some point in time replaced the original 5 amp fuse with a 10 amp automotive fuse...:scratch2::nono::thumbsdn:

Would almost make me wonder if there was some issue years ago that was causing the fuse to blow and that's why they quit using it.
Mind you it could have been replaced more recently by someone plugging it in to see if it worked so that they could as more for it on ebay.....

Yes powered on with tubes in sockets.

OK well a little problem, when I was replacing some of the capacitors I replaced a couple of .05 MFD capacitors with what I thought were some .047 MFD capacitors but then when I looked at the code on it again I realized it said 472 rather than 473 on it so right now I really can't power on the TV because of it having the wrong value of capacitors in a couple of spots.

I do have a list of the capacitors I need though drawn up, including the electrolytics I didn't replace yet, and interestingly enough this TV uses all of the basic capacitor values like .1, .01, .047, .0047, and .033 (which actually the last one is .035 but .033 will work fine I in its place I think).

Would almost make me wonder if there was some issue years ago that was causing the fuse to blow and that's why they quit using it.
Mind you it could have been replaced more recently by someone plugging it in to see if it worked so that they could as more for it on ebay.....

Well actually now that you mention it, on the bottom side of the TV chassis by the High Voltage Cage there appears to be a huge char mark on the chassis like maybe something caught fire under there or something but I'm not sure.

Before investing further effort and $$ in that set, it'd be advisable to check the no-load current draw of the power xfmr, considering the xfmr has a history of being brutalized over and over.

Remove all the tubes (except HV rect), disconnect CRT from its socket, power up and measure AC current draw from the wall. This 'idle' current should be very low. If it's excessive, suspect some cooked windings in the xfmr.

Before investing further effort and $$ in that set, it'd be advisable to check the no-load current draw of the power xfmr, considering the xfmr has a history of being brutalized over and over.

Remove all the tubes (except HV rect), disconnect CRT from its socket, power up and measure AC current draw from the wall. This 'idle' current should be very low. If it's excessive, suspect some cooked windings in the xfmr.

Yes agreed this would be a excellent plan.
Lets hope that the flyback isn't cooked.:yes:

Lets hope that the flyback isn't cooked.:yes:
The fly shouldn't be affected since it was not in the current path of the B+ short.

Before investing further effort and $$ in that set, it'd be advisable to check the no-load current draw of the power xfmr, considering the xfmr has a history of being brutalized over and over.

Remove all the tubes (except HV rect), disconnect CRT from its socket, power up and measure AC current draw from the wall. This 'idle' current should be very low. If it's excessive, suspect some cooked windings in the xfmr.

OK, that's easy enough to do.

Before investing further effort and $$ in that set, it'd be advisable to check the no-load current draw of the power xfmr, considering the xfmr has a history of being brutalized over and over.

Remove all the tubes (except HV rect), disconnect CRT from its socket, power up and measure AC current draw from the wall. This 'idle' current should be very low. If it's excessive, suspect some cooked windings in the xfmr.

Well the only problem is, that as I pointed out in a previous post I have accidentally replaced two .05 MFD capacitors with 2 .0047 MFD capacitors because I misread the capacitor code on the outside of the capacitors, which I thought they said 473K on them but then after I installed them in the TV set I looked at the code marker again and saw that it actually said 472K not 473K like I thought it did.
So I have two capacitors in the TV that are outside of the tolerance rating of the original capacitors so I'm afraid to power it up until I get those capacitors replaced with the correct value capacitors which I currently don't have any .047 MFD 630 VDC capacitors in my capacitor stash.

I don't want to order anything yet unless I can make a full order and I can't do that until I know this thing is going to be worth my time ordering the rest of the capacitors I need to finish the job and I don't want to put an order in for just two capacitors because that's a waste.

Does anyone have a couple of .047 MFD 630 VDC film capacitors that they could spare?

Well the only problem is, that as I pointed out in a previous post I have accidentally replaced two .05 MFD capacitors with 2 .0047 MFD capacitors because I misread the capacitor code on the outside of the capacitors, which I thought they said 473K on them but then after I installed them in the TV set I looked at the code marker again and saw that it actually said 472K not 473K like I thought it did.
So I have two capacitors in the TV that are outside of the tolerance rating of the original capacitors so I'm afraid to power it up until I get those capacitors replaced with the correct value capacitors which I currently don't have any .047 MFD 630 VDC capacitors in my capacitor stash.

I don't want to order anything yet unless I can make a full order and I can't do that until I know this thing is going to be worth my time ordering the rest of the capacitors I need to finish the job and I don't want to put an order in for just two capacitors because that's a waste.

Does anyone have a couple of .047 MFD 630 VDC film capacitors that they could spare?

The test he suggests (pull every tube and power up for a current measurement) will work accurately no matter what capacitance you installed for paper caps...Basically, there will be no tubes to put signal into or take signal out of those caps, there won't even be B+ voltage anywhere...THe only part that should be energized is the power transformer...You could probably glue a pair of leads to a rock, solder that in place of the caps your scared of and not have it do harm or affect the results of the suggested test.

The point here is to verify the expensive/rare power transformer does not have an internal short/current leakage (read that verify the trans ain't ruined). If it don't draw too much current order all the caps when you have the dough, if it draws too much current shelve the set for a few months till you can track down a good transformer or kick it down the road to its next owner.

The test he suggests (pull every tube and power up for a current measurement) will work accurately no matter what capacitance you installed for paper caps...Basically, there will be no tubes to put signal into or take signal out of those caps, there won't even be B+ voltage anywhere...THe only part that should be energized is the power transformer...You could probably glue a pair of leads to a rock, solder that in place of the caps your scared of and not have it do harm or affect the results of the suggested test.

The point here is to verify the expensive/rare power transformer does not have an internal short/current leakage (read that verify the trans ain't ruined). If it don't draw too much current order all the caps when you have the dough, if it draws too much current shelve the set for a few months till you can track down a good transformer or kick it down the road to its next owner.

OK thanks that's what I wanted to know. I'll proceed with the test then, since I don't actually have to fear ruining the set with the wrong value capacitors in it with this test, that was my main concern.

OK thanks that's what I wanted to know. I'll proceed with the test then, since I don't actually have to fear ruining the set with the wrong value capacitors in it with this test, that was my main concern.

To put things into perspective for you, powering the set with all those original leaky paper and electrolytic caps has been much more risky than if you powered it with the two off-value new caps installed.

OK so a little update, I powered on the set with all but the H. V. Rectifier tube removed from the TV and the TV's current draw leveled out at about .39 Amps or 7.3 watts according to my Kill-A-Watt Meter, which is fairly low.

So I'm guessing that the transformer is actually fine yet and my problem is just a bunch of paper caps that have shorted to ground somewhere in the TV (more than likely the two .01 MFD caps on the AC line for noise supression are the ones to blame because they are soldered to ground on one side and if they've shorted, they've more than likely shorted to ground.)

OK so a little update, I powered on the set with all but the H. V. Rectifier tube removed from the TV and the TV's current draw leveled out at about .39 Amps or 7.3 watts according to my Kill-A-Watt Meter, which is fairly low.

So I'm guessing that the transformer is actually fine yet and my problem is just a bunch of paper caps that have shorted to ground somewhere in the TV (more than likely the two .01 MFD caps on the AC line for noise supression are the ones to blame because they are soldered to ground on one side and if they've shorted, they've more than likely shorted to ground.)

I doubt the AC line caps are drawing all that current. They'd of exploded by now with unlimited AC current flowing. You can simply snip one lead of those so they are out of circuit. They are not needed for the set to be operational.

Scratches head... how does 122 Volts @ .39 Amps equal only 7.3 Watts? :scratch2:

jr

Scratches head... how does 122 Volts @ .39 Amps equal only 7.3 Watts? :scratch2:

jr

Answer: power factor for this unloaded power transformer must be quite small, about 0.15 !

Just measured an unloaded tv power transformer of similar size on a kill-a-watt meter, readings were:
122 Volts, 0.26Amps, 9 Watts, 34 VA, 60Hz, 0.28 PF (power factor), so I believe that the PF could be as low as 0.15. :scratch2:
Did you happen to get a power factor reading?

jr

Answer: power factor for this unloaded power transformer must be quite small, about 0.15 !

Just measured an unloaded tv power transformer of similar size on a kill-a-watt meter, readings were:
122 Volts, 0.26Amps, 9 Watts, 34 VA, 60Hz, 0.28 PF (power factor), so I believe that the PF could be as low as 0.15. :scratch2:
Did you happen to get a power factor reading?

jr

Here are my Kill-A-Watt Meter readings for my TV's Unloaded Transformer:

123.4 Volts AC
0.40 Amperes
8.2 Watts
50.6 VA
60.0 Hz
PF (Power Factor) 0.16

Hope this helps.

P. S. depending on the time of the day my voltage readings coming out of my outlets can range between 119.8 VAC and 124.5 VAC, when I took my Kill-A-Watt Readings just now my Voltage reading was 123.4 VAC when I took it this morning it was 122.5 VAC.

So, because of the low power factor of the unloaded transformer, the .40 Amp current draw does not appear to be excessive at all. Your transformer is behaving much the same as the known good transformer that I measured and is probably good.

jr

So, because of the low power factor of the unloaded transformer, the .40 Amp current draw does not appear to be excessive at all. Your transformer is behaving much the same as the known good transformer that I measured and is probably good.

jr

That's good to know and is basically what I was thinking.

So it definitely means that more than likely my problem lies with some bad paper caps in the TV that have shorted to ground more than likely.
Probably more than likely one of the paper caps that I have yet to replace.
Which I have already replaced almost half the capacitors in the set already, I have about 23 more capacitors to replace in this set yet (that includes some of the electrolytics that I haven't replaced yet in the set).

It's nice to see those reading off the transfomer. I was begining to wonder about a internal short as well.
Once those caps are changed it will make a big difference.
The heavy current load that was causing the rectifer to arc could have been partly due to some of the remainding old electrolytics trying to reform.
When they haven't had any voltage for long time they will pull a lot of current.

In the future it would be wise to power up a set like this with a dim bulb tester. That way you'll at least have a visual indication that there's excessive current being drawn before hitting the transformer with the whole shebang. Also make sure the set has the proper size fuse from the get go.

In the future it would be wise to power up a set like this with a dim bulb tester. That way you'll at least have a visual indication that there's excessive current being drawn before hitting the transformer with the whole shebang. Also make sure the set has the proper size fuse from the get go.

Ok, will do.
What size of bulb should I use on something like this?
I know certain size incandescent bulbs are no longer available.

Ok, will do.
What size of bulb should I use on something like this?
I know certain size incandescent bulbs are no longer available.

You're right that large wattage bulbs are getting harder to find. Two or three 60 watts in parallel should get you in the range. You can experiment with a properly working TV to find the sweet spot were the bulb is just starting to light.

You're right that large wattage bulbs are getting harder to find. Two or three 60 watts in parallel should get you in the range. You can experiment with a properly working TV to find the sweet spot were the bulb is just starting to light.
If you go through to various thrift shops, you'll find all kinds of incandescent lamps of all wattages. Many people stocked on lamps and now they're getting rid of them for LED's.

You're right that large wattage bulbs are getting harder to find. Two or three 60 watts in parallel should get you in the range. You can experiment with a properly working TV to find the sweet spot were the bulb is just starting to light.

I found at my local supermarket a 150 watt incandescent bulb, would that work?

If you go through to various thrift shops, you'll find all kinds of incandescent lamps of all wattages. Many people stocked on lamps and now they're getting rid of them for LED's.

Thanks, I checked all my thriftshops near me and the biggest bulbs they had were 60 watt bulbs.

:thmbsp: Guys , check the shelves of your local Home Depot . For real .

Last week I was at HD looking for a specific bulb when I happened across these two 150 Watt bulbs for a couple of Dollars a piece . There were two on the shelf , so I bought two . I'd have bought as many as they had , thinking I'd stepped through some kind of time warp or something , but when I asked the guy in the electrical department he said they are a regular item , being so called "utility" bulbs they aren't subject to any kinds of restrictions .

I found at my local supermarket a 150 watt incandescent bulb, would that work?

:D you posted while I was typing , and as per my post above sure the 150 Watt bulb you bought will be fine .

..Two or three 60 watts in parallel should get you in the range.

¡Aye caramba! :eek: That won't give a soft start. Start with a low wattage bulb first, then work up in stages. Say 15W, 40W, 60W, 100W.

:thmbsp: Guys , check the shelves of your local Home Depot . For real .

Last week I was at HD looking for a specific bulb when I happened across these two 150 Watt bulbs for a couple of Dollars a piece . There were two on the shelf , so I bought two . I'd have bought as many as they had , thinking I'd stepped through some kind of time warp or something , but when I asked the guy in the electrical department he said they are a regular item , being so called "utility" bulbs they aren't subject to any kinds of restrictions .

I found 150 Watt Incandescent Bulbs at my local supermarket.

Thanks for the suggestion though!

¡Aye caramba! :eek: That won't give a soft start. Start with a low wattage bulb first, then work up in stages. Say 15W, 40W, 60W, 100W.
That's why I suggested testing different wattage's with a working TV a couple posts up. I suppose you could even use one of those 3 way switched bulbs for selecting different ranges. But I think a TV that uses 180 watts is going to drop too much voltage across a 15 watt ;)

That's why I suggested testing different wattage's with a working TV a couple posts up. I suppose you could even use one of those 3 way switched bulbs for selecting different ranges. ;)

I have a mogul base 3 way socket from an old floor lamp from the 1950s and a mogul base 3-way light bulb that's rated 100-200-300 watts, I could probably wire that up as a dim-bulb tester and just turn the 3 way socket on to the various wattages until the bulb dims when the set is on when it has been recapped, to check proper working order of the set.

I have a mogul base 3 way socket from an old floor lamp from the 1950s and a mogul base 3-way light bulb that's rated 100-200-300 watts, I could probably wire that up as a dim-bulb tester and just turn the 3 way socket on to the various wattages until the bulb dims when the set is on when it has been recapped, to check proper working order of the set.

200-300 watts would be too much for your set. I wasn't really serious about the 3 way. Like OC suggested just try different wattage bulbs starting with a lower wattage. A lower wattage bulb will have higher resistance than a higher wattage, which is why it will drop more voltage and provide a softer start. But if it's too low it also won't allow the TV to get enough voltage.

200-300 watts would be too much for your set. I wasn't really serious about the 3 way. Like OC suggested just try different wattage bulbs starting with a lower wattage. A lower wattage bulb will have higher resistance than a higher wattage, which is why it will drop more voltage and provide a softer start. But if it's too low it also won't allow the TV to get enough voltage.

I also have a variac, but its currently not wired up, it needs a box, an outlet and a power cord. Anyone have instructions for wiring up a variac?

Pictures of the variac in question posted below.

I also have a variac, but its currently not wired up, it needs a box, an outlet and a power cord. Anyone have instructions for wiring up a variac?

Pictures of the variac in question posted below.

The directions for wiring are printed right on the back, no?

Here's a pretty good tutorial on how the dim bulb tester works.

https://www.youtube.com/watch?v=zhQEP-Y_OUU

The directions for wiring are printed right on the back, no?


Yes, but I don't know whether or not a regular duplex style outlet would work with this variac setup or whether I would need to use just a single outlet for this setup, and I don't know whether or not this particular variac would support grounded wiring (grounded cord and grounded outlet), and how would I go about marking the voltage calibrations on the box for the knob once I got it wired up and installed in a box so I know what voltage I'm on when turning the knob.

Here's a pretty good tutorial on how the dim bulb tester works.

https://www.youtube.com/watch?v=zhQEP-Y_OUU

I already have a general idea of how a dimbulb tester works, I just wanted some instructions on how to get my variac going so I could use it in the future, because I've never owned or used a variac before let alone wire one up from scratch before so that's why a little help would be nice in getting me started on wiring up my variac and getting running properly.

Single or double outlet don't matter...my factory made variac has a single outlet, but I plug a 3 way splitter in sometimes. It is a wise idea to put a circuit breaker on the input so if you plug a short into it it don't fry.

A good way to calibrate it once you have a box and knob with pointer is to plug a 40- 60w bulb in with a volt meter connected to the output. Every 10V make a line and label the output voltage every 5v make a dot. Best calibration would be with the input voltage at 120v or 125v. If you know you get say 50v at a knob position with an input of 120v you can take that ratio and mathematically determine the output if the line input voltage is something else.

A while ago I read the president got rid of that stupid law that was phasing out incandescent bulbs...We should see higher wattage incandescent bulbs return to store shelves. :thmbsp:

A while ago I read the president got rid of that stupid law that was phasing out incandescent bulbs...We should see higher wattage incandescent bulbs return to store shelves. :thmbsp:

Didn't know that had happened. Sweet!

Single or double outlet don't matter...my factory made variac has a single outlet, but I plug a 3 way splitter in sometimes. It is a wise idea to put a circuit breaker on the input so if you plug a short into it it don't fry.

A good way to calibrate it once you have a box and knob with pointer is to plug a 40- 60w bulb in with a volt meter connected to the output. Every 10V make a line and label the output voltage every 5v make a dot. Best calibration would be with the input voltage at 120v or 125v. If you know you get say 50v at a knob position with an input of 120v you can take that ratio and mathematically determine the output if the line input voltage is something else.

A while ago I read the president got rid of that stupid law that was phasing out incandescent bulbs...We should see higher wattage incandescent bulbs return to store shelves. :thmbsp:

Thanks I'll give that a try. I'll definitely see if I can get my dim bulb tester and my variac wired up.

Thanks I'll give that a try. I'll definitely see if I can get my dim bulb tester and my variac wired up.

If you have an isolation transformer and some voltage and current meters you could probably build it all into one all purpose tube equipment power box...:thmbsp:

If you have an isolation transformer and some voltage and current meters you could probably build it all into one all purpose tube equipment power box...:thmbsp:

unfortunately I don't have any voltmeters or current meters and I don't have any isolation transformers either, and I don't know where I would get those things.

This rather inexpensive item solves a lot of the questions about current, voltage, wattage etc.

But the item above is not an isolation transformer.

If you have a pair of the same model appliance you don't mind scaping that draws 100W or more you can make your own isolation transformer out of a pair of step-down or step-up transformers.

Let's assume a 120V primary and that there is only one secondary (or only one secondary that uses a significant amount of power which will be the only secondary used). To make a bench isolation transformer out of 2 identical power transformers wire a power cord onto the primary of the first transformer, and a power outlet onto the primary of the other transformer, and lastly, connect the secondary of the first transformer to the secondary of the second transformer.

Do you shop thrift stores often? If so keep an eye out for those Uninterruptable Power Supplies used with computers. They look like shoebox-sized power strips. If you can find 2 of the same model they would be perfect. The secondaries are low voltage and beefy (use the secondary with thick wire). Those should be able to isolate a radio and most TVs easily.

I usually look for purpose-built isolation transformers at antique radio/ham swap meets rather than make them.

Here is another dirty trick based on the same principle. If you ever encounter a radio where the AC primary of the transformer has opened and you know the heater winding is 6.3V you can take a similar sized transformer with a 6.3V heater winding and connect it to the heater winding of the damaged transformer to power the set.

Here is another dirty trick based on the same principle. If you ever encounter a radio where the AC primary of the transformer has opened and you know the heater winding is 6.3V you can take a similar sized transformer with a 6.3V heater winding and connect it to the heater winding of the damaged transformer to power the set.

I'm not sure if all radio transformers would have that 6.3v filament winding of heavy enough gauge to support the total VA of the radio passing though it.

Its easy to find big fat toroidal transformers on ebay or Amazon. Many have multiple
115 volt windings that can be used as an isolation transformer or to make a step up or down 115-230 volt transformer. Some have lower voltage windings that can be wired in for small steps up or down and still have, unlike a Variac, isolation.

This rather inexpensive item solves a lot of the questions about current, voltage, wattage etc.

that's what I have and have been using, what I and Electronic M was talking about was an actual gauge that you had to physically wire into the box of the vairac and isolation transformer so you could monitor the voltage and current draw of the electronic device being brought up on the variac.

that's what I have and have been using, what I and Electronic M was talking about was an actual gauge that you had to physically wire into the box of the vairac and isolation transformer so you could monitor the voltage and current draw of the electronic device being brought up on the variac.

There's nothing wrong with using your killowatt meter in conjunction with the dim bulb setup. The reason for using the light bulb in series with the TV is to limit the current in the event there's some defective components.

Kill-A-Watt always goes first in the connection line. If not, it may not work/indicate.

There's nothing wrong with using your killowatt meter in conjunction with the dim bulb setup. The reason for using the light bulb in series with the TV is to limit the current in the event there's some defective components.

I know. I was just trying to say that I had already been using a Kill-A-Watt meter this whole time.

If you want you can use the kilawatt with the box I suggested building one (as well as every other power device you would likely want) in to it because separate parts tend to get lost and not be there when one needs them...

I've been contemplating building such a box for years, but already having separates (and having an isolation trans short primary to secondary) and lazyness have stopped me.

If you want you can use the kilawatt with the box I suggested building one (as well as every other power device you would likely want) in to it because separate parts tend to get lost and not be there when one needs them...

I've been contemplating building such a box for years, but already having separates (and having an isolation trans short primary to secondary) and lazyness have stopped me.

Ok, that's what I was thinking of doing as well. But I wasnt sure that's what you meant as well.

I've put in an order for 2 of the electrolytics and tomorrow I will be putting in an order for the rest of the capacitors I need for the TV.

OK, so I just figured out that that R28 a 1,000 Ohm 1/2 Watt Resistor and R93 a 15 Ohm 1/2 Watt resistor of which both serve as Bias Network Resistors were both way out of tolerance (way outside the +/-20% tolerance that those resistors were rated for) the 1,000 Ohm resistor measured at 1,488 Ohms, and the 15 Ohm Resistor measured at 32 Ohms, so with that in mind, would out of spec Bias Network Resistors cause the Low Voltage Rectifier to arc, and nearly redplate?

Also the 500 MFD 5 VDC Capacitor, aka the Bias Filter Cap measured at over a thousand MFD which means it was bad I'm guessing.

Also Is it normal for a brand new electrolytic capacitor to measure over 10% high in value? I'm asking because my brand new 470 MFD 16 VDC capacitor that was supposed to replace the old 500 MFD 5 VDC capacitor measured at over 520 MFD as opposed to 470 MFD.

well the rest of my capacitors came in the mail yesterday and I've been able to replace almost all of the capacitors in the TV except for the electrolytics that I hadn't replaced yet, and a few paper caps.

The thing thats holding me up is that 15 ohm 1/2 watt bias network resistor that had became a 32 Ohm resistor over time, its such an oddball value that I didn't even have any in my resistor stock that I had bought from radio shack before they closed up shop near me, and radio shack has that part and its only $1 and some change including tax which I would rather pay that for the part than having to pay $8 for the part (the price of the part including shipping and tax).

So no one on here has answered my question regarding the bias network resistors, would bad bias network resistors cause my low voltage rectifier tube to arc and redplate especially if they were drifted up in value way past the 20% tolerance range of the part?

So no one on here has answered my question regarding the bias network resistors, would bad bias network resistors cause my low voltage rectifier tube to arc and redplate especially if they were drifted up in value way past the 20% tolerance range of the part?
No. If that 15Ω resistor (or any resistor 'downstream' of it it) drifts upward, it will not increase load on the 5U4. In fact if the 15Ω drifts upward, it will reduce the load very slightly. Conversely, if it were dead shorted (say the 500µf cap across it were shorted), it would increase the load very slightly.

No. If that 15Ω resistor (or any resistor 'downstream' of it it) drifts upward, it will not increase load on the 5U4. In fact if the 15Ω drifts upward, it will reduce the load very slightly. Conversely, if it were dead shorted (say the 500µf cap across it were shorted), it would increase the load very slightly.

Ok, thanks. I was just making sure.
I will continue on with the recap process and replacing the resistor.

The thing thats holding me up is that 15 ohm 1/2 watt bias network resistor that had became a 32 Ohm resistor over time, its such an oddball value that I didn't even have any in my resistor stock that I had bought from radio shack before they closed up shop near me, and radio shack has that part and its only $1 and some change including tax which I would rather pay that for the part than having to pay $8 for the part (the price of the part including shipping and tax).


When ordering parts from online vendors the worst way to do it is to order 1-9 pieces of 1-9 different parts at a time....you don't hit volume price breaks and your paying $8 for parts that fit in a $1 greeting card envelope.

The best way to do it is to buy $100+ of parts once every 6-24 months, set it up so you stock 10-100 of each value cap and or resistor you may need for any set your likely to encounter. And only restock when you need enough of enough different parts to hit the price breaks on over a dozen things. Building that stock is expensive so start with the think you need most and every reorder pad with some parts you need less often until your stock is good...

If you buy 100 15ohm resistors at $0.05 a pop and had 32 other different parts on the same order then your 15ohm resistors cost $0.25 to ship divide that by 100 and each 15ohm resistor costs 2.5 cents to ship for a total investment of 7.5 cents per resistor...or $5.25 for 100 15ohm resistors. Now contrast that to radio shack at let's say $1 for 2 resistors...if you buy 100 resistors that is $50 throw in the gas to drive there and you are at over 10x the price of ordering in bulk online....

They will let you claim that $8 flat rate shipping option if you buy 2000 pieces (200 different part numbers at 100 pieces each part)...If you buy over 800 pieces online (regardless of whether it is 1 sample of each cap and resistor you could ever want or 800 identical parts) the shipping cost per part is less than 1cent...

I have been known to put some projects on hold for months till I need to fire off a large part order so 1-3 parts I don't stock can get nearly free shipping on a bulk restock order.

Radio shack and frequent small online orders you end up paying a lot for convenience...If you do a lot of resto work, money is tight and or a resto is not a rush job think about how much money you are throwing away on convenience...

When ordering parts from online vendors the worst way to do it is to order 1-9 pieces of 1-9 different parts at a time....you don't hit volume price breaks and your paying $8 for parts that fit in a $1 greeting card envelope.

The best way to do it is to buy $100+ of parts once every 6-24 months, set it up so you stock 10-100 of each value cap and or resistor you may need for any set your likely to encounter. And only restock when you need enough of enough different parts to hit the price breaks on over a dozen things. Building that stock is expensive so start with the think you need most and every reorder pad with some parts you need less often until your stock is good...

If you buy 100 15ohm resistors at $0.05 a pop and had 32 other different parts on the same order then your 15ohm resistors cost $0.25 to ship divide that by 100 and each 15ohm resistor costs 2.5 cents to ship for a total investment of 7.5 cents per resistor...or $5.25 for 100 15ohm resistors. Now contrast that to radio shack at let's say $1 for 2 resistors...if you buy 100 resistors that is $50 throw in the gas to drive there and you are at over 10x the price of ordering in bulk online....

They will let you claim that $8 flat rate shipping option if you buy 2000 pieces (200 different part numbers at 100 pieces each part)...If you buy over 800 pieces online (regardless of whether it is 1 sample of each cap and resistor you could ever want or 800 identical parts) the shipping cost per part is less than 1cent...

I have been known to put some projects on hold for months till I need to fire off a large part order so 1-3 parts I don't stock can get nearly free shipping on a bulk restock order.

Radio shack and frequent small online orders you end up paying a lot for convenience...If you do a lot of resto work, money is tight and or a resto is not a rush job think about how much money you are throwing away on convenience...

I understand what you are saying and I would seriously think about doing that if I didn't have such a tight budget to work with, and also the fact that I don't do enough repair jobs/restorations to warrant me stocking up on nearly 1000 parts just to get free shipping, it just isn't something I can do right now unfortunately.

Otherwise I would be doing what you suggested.

I'm sure Mr M. remembers saving up his allowance so he could buy a handful of capacitors, back before he became independently wealthy. :D

I understand what you are saying and I would seriously think about doing that if I didn't have such a tight budget to work with, and also the fact that I don't do enough repair jobs/restorations to warrant me stocking up on nearly 1000 parts just to get free shipping, it just isn't something I can do right now unfortunately.

Otherwise I would be doing what you suggested.


I honestly have probably never hit the 800 part order threshold, but I do try to make my orders as few and big as I can to maximize price break and shipping ecconomy (read that minimize cost per item in my stock).

It isn't necessary to hit any of the volume price breaks... however planning buying to do as much of that as practical for you saves you money in the long run.

Not to sound rude but complaining about spending $8 shipping to get a single 10 cents part here in a week and prefering to spend $1 on a local part that should cost 10 cents seems like a logically conflicted argument. So a cheaper alternative was suggested.

When it comes to anything new I am as cheap as they come, and proud of it!

I'm sure Mr M. remembers saving up his allowance so he could buy a handful of capacitors, back before he became independently wealthy. :D

Yeah, I wish that were the case for me. Unfortunately working part time as a custodian at an Amish themed restaurant doesn't pay as well you might think (although it pays much better than goodwill does.)
And then I just bought a new car that I took out a loan for so I have car payments so really it's not an option for me to be buying $300 worth of parts right now just to get free shipping.
So while I express that paying twice cost of the parts I needed in shipping is annoying, it's all I can do right now unfortunately.

I honestly have probably never hit the 800 part order threshold, but I do try to make my orders as few and big as I can to maximize price break and shipping ecconomy (read that minimize cost per item in my stock).

It isn't necessary to hit any of the volume price breaks... however planning buying to do as much of that as practical for you saves you money in the long run.

Not to sound rude but complaining about spending $8 shipping to get a single 10 cents part here in a week and prefering to spend $1 on a local part that should cost 10 cents seems like a logically conflicted argument. So a cheaper alternative was suggested.

When it comes to anything new I am as cheap as they come, and proud of it!

Well the problem is that with digikey and Mouser, in order to get free shipping you have to make a minimum $80 order, and none of my orders ever reach that minimum.

Plus when I get old radios, record players or TVs to fix up, I never know what value of capacitors are going to be in it until I open it up or look up the service manual, and seeing as half the time when I get an old radio or record player from someone I don't know what the model is until it's in my hands.

So it's kind of hard to make a bulk order of capacitors when half the time I don't even know what I'm going to need until I get the radio, record player or tv.

So to me just ordering the capacitors once I know what I need makes more sense, seeing as no two radio, record player or TV circuits are the same when it comes to what parts they will need it's kind of hard to know what parts to order in bulk and what not to order in bulk.

Well the problem is that with digikey and Mouser, in order to get free shipping you have to make a minimum $80 order, and none of my orders ever reach that minimum.

Plus when I get old radios, record players or TVs to fix up, I never know what value of capacitors are going to be in it until I open it up or look up the service manual, and seeing as half the time when I get an old radio or record player from someone I don't know what the model is until it's in my hands.

So it's kind of hard to make a bulk order of capacitors when half the time I don't even know what I'm going to need until I get the radio, record player or tv.

So to me just ordering the capacitors once I know what I need makes more sense, seeing as no two radio, record player or TV circuits are the same when it comes to what parts they will need it's kind of hard to know what parts to order in bulk and what not to order in bulk.
Ordering exactly what you would need in advance of purchase and no more is basically impossible, but there are good ways of estimating approximate future need...in the earliest days of my restoration (when I was 10-15 years old) I my folks would only take me to places I could buy parts 1-4 times a year...I made and never discarded shopping lists and when I started pre-stocking parts to be ready to fix 80 percent of sets immediately (even if randomly given to me that day) I estimated what I need to stock in bulk by tallying up how many of each part I bought in a year's time and or how much I bought since I started and the hand full of values I needed most were the first to be bulk stocked.

Things less commonly needed like resistors you can if you keep your eyes open at swapmeets periodically find large assortments of for cheap....near the end of my no money period I found a couple of lots like that which I'm only now deleting to the point where I'm considering buying an assortment of new parts to replace (NOS carbon comp resistors sometimes are just as troublesome as the originals).

Ordering exactly what you would need in advance of purchase and no more is basically impossible, but there are good ways of estimating approximate future need...in the earliest days of my restoration (when I was 10-15 years old) I my folks would only take me to places I could buy parts 1-4 times a year...I made and never discarded shopping lists and when I started pre-stocking parts to be ready to fix 80 percent of sets immediately (even if randomly given to me that day) I estimated what I need to stock in bulk by tallying up how many of each part I bought in a year's time and or how much I bought since I started and the hand full of values I needed most were the first to be bulk stocked.

Things less commonly needed like resistors you can if you keep your eyes open at swapmeets periodically find large assortments of for cheap....near the end of my no money period I found a couple of lots like that which I'm only now deleting to the point where I'm considering buying an assortment of new parts to replace (NOS carbon comp resistors sometimes are just as troublesome as the originals).

Yes, but the problem is that I don't have radio swap meets near me and I don't have any local electronics parts retailers near me anymore (radio shack is gone and there aren't any Fry's Electronics Stores near me either.)
The only way I can get capacitors and resistors for my repair projects is through online outlets like Antique Electronics Supply, Mouser, Digikey, Parts Express, etc. and like I said none of the radios, or record players I've worked on so far in my 15 years of working on vintage electronics have had the same values of capacitors in them (there wasn't any "standard" values in the radios or record players that I could go by to just guess what values of capacitors I was going to need in the future to order well in advance for future projects).

To illustrate what I'm talking about:
about 10 years ago worked on an old Delco radio from 1937 and it had capacitors like .01 MFD, .02 MFD, .03 MFD, .1 MFD, etc, and I unfortunately had an issue with the radio where I ended up having to remove the brand new capacitors I put into the radio and scrap the radio out because the speaker cone got damaged beyond repair and so I had those capacitors from that old Delco radio sitting in my parts stash for over 8 years before I ended up finding another radio that used those values so that I could finally use some of those capacitors that had been sitting in my capacitor stash that whole time.

So now you know why it is that I don't like to order things in advance or try to "stock up" on random capacitor values because more than likely with the way things have been for me, most of them will just sit in my stash for several years before finally getting used, which to me is a waste of money to sink $100+ into bulk ordering random capacitor values when most of them will more than likely never be used or will sit for several years before finally being used.

.01 and .1 are 2 of the most commonly used values and the ones I stock in the highest quantity (not uncommon for me to replace 100 of those in a year)....you must have barely been working on anything or working on a lot of oddball stuff to not have used them for 8 years! :yikes:

The others while not as high usage ain't exactly oddballs either.

With the number of threads you post I figured you'd be working on more stuff than that tale implies.

.01 and .1 are 2 of the most commonly used values and the ones I stock in the highest quantity (not uncommon for me to replace 100 of those in a year)....you must have barely been working on anything or working on a lot of oddball stuff to not have used them for 8 years! :yikes:

The others while not as high usage ain't exactly oddballs either.

With the number of threads you post I figured you'd be working on more stuff than that tale implies.

Well a lot of my messages are asking about stuff that I see at flea markets and antique malls and seeing if I should bother getting it or not, which some of that stuff I've passed on, because you guys said the price was too much for what it was.

Also I've had many radio projects over the years that I just had to scrap out because they had too many issues with them that wasn't worth my time fixing.

I've worked on probably 40 radios and record players over the course of 15 years and I've only had about 20 of them that were successful repairs that I had either kept or sold, the rest were junked out for various reasons including bad wiring, bad speaker, or I just couldn't get the radio to receive any stations no matter how many tubes or IF cans I replaced.

So no, it isn't surprising that I had sat on those capacitors for 8 years before using them, and that's because I only bought or was given maybe 2 radios a year for most of that time. It's only been within the past 6 years that I've been able to get more than 2 radios a year.

I order from "just radios" they have a $20 min, but on average it cost that much just for the electrolytic's. They ship it with a packing list that has the part number printer on the caps listed next to the value so it makes it easy to identify the bag of parts. I have been trying to "stock up" on the ones I use the most.

OK, so a little update, I replaced EVERY capacitor there was to replace in this TV and the TV is still drawing way too much current somewhere because the wattage draw on the TV powering it up was approaching 400 watts and the rectifier tube was still arcing.

Any ideas of where else I could look?

I know its not the power transformer or the choke as I tested those without the tubes in and the current draw was normal.

Could it be my flyback or something in my high voltage section, if so how do I check?

OK, so a little update, I replaced EVERY capacitor there was to replace in this TV and the TV is still drawing way too much current somewhere because the wattage draw on the TV powering it up was approaching 400 watts and the rectifier tube was still arcing.

Any ideas of where else I could look?

I know its not the power transformer or the choke as I tested those without the tubes in and the current draw was normal.

Could it be my flyback or something in my high voltage section, if so how do I check?
Unlikely, but pulling the horizontal output tube would be a good way to check....your power consumption should drop well below the rating with the H out pulled.

You probably have a short somewhere down stream of the choke.... such as in the focus coil circuit or one of the loads on the B+ lines.

You only followed a fraction of the short tracing procedure I laid out on a previous page of this thread...you should be better served following that method to the end/extending it to the loads on the line than grabbing chit outa a hat and throwing it at a wall in hopes of something sticking...

Unlikely, but pulling the horizontal output tube would be a good way to check....your power consumption should drop well below the rating with the H out pulled.

You probably have a short somewhere down stream of the choke.... such as in the focus coil circuit or one of the loads on the B+ lines.

You only followed a fraction of the short tracing procedure I laid out on a previous page of this thread...you should be better served following that method to the end/extending it to the loads on the line than grabbing chit outa a hat and throwing it at a wall in hopes of something sticking...

Actually I figured out what the problem was, I had the filter choke wired up wrong, and fixed it, now the low-voltage issue is fixed, but now there's something going on with the tuner as there is some smoke coming out of it when I power on the the TV and let tubes warm up, it smells like it might be a resistor or something because it has a sort of "old dust" smell similar to the smell you get when you first turn your furnace on for the first time in the fall.

OK new problem now, my power switch now is arcing and sparking out of nowhere, and I have no idea why its doing that.

I took the tuner apart and the only parts in there are a couple of ceramic caps and several resistors of which none of those parts look burnt so I sprayed some contact cleaner in the tuner on the contacts and worked the tuner knob around.

But as for the power switch/volume control and it arcing like it is, I'm not sure why it would be doing that.

Any ideas?

OK so I figured out two of my problems that had cropped up, the issue with the smoking tuner was the tube I was using in my tuner, the 6AG5 tube of the tuner (which I didn't have any of to put into the tuner when I got the TV because that was one of the many tubes that was missing in the TV when I got it) was substituted out for a 6AK5 (which my tube substitution guide told me that was an appropriate substitute for a 6AG5 tube) but apparently the 6AK5 in this situation wasn't an appropriate sub for the 6AG5 as I think it was pulling more current than the tuner circuit could handle because once I swapped out the 6AK5 with a 6CB6 the tuner didn't smoke anymore.

As for the arcing power switch it was the rectifier tube I was using because I was trying some different 5U4 tubes in the TV and apparently the 5U4 tube I had stuck into the TV had some issues with it that only showed up when it was in circuit because when I stuck another 5U4 tube in the circuit the power switch stopped arcing.

but then yet another issue popped up, and it was in the audio circuit, R62, a 390 Ohm 1 watt resistor suddenly started smoking, and I'm not sure why, but I did have a raster on the screen of the TV just before I noticed the smoke from this resistor which I then promptly shut off the TV.

I did measure the 390 Ohm resistor and it measured extremely out of tolerance, it measured .475k Ohms which when I went to measure it in ohms it just measured O. L. on my multimeter.

I don't have any 390 Ohm 1 Watt resistors but I do have a 330 Ohm 1 Watt resistor, would that work, in place of the 390 Ohm resistor?

I did check and the resistor tolerances in the TV are 20% and 330 ohms is within the 20% tolerance of the original part.

I actually did have some 390 Ohm 1 watt resistors in my stash, I replaced the original one with one of the ones I had in my stash and its still wanting to smoke for some reason, and I can't figure out why...

I'm so close to getting this TV going and this one resistor wanting to smoke is keeping me from getting there... :sigh: :tears:

OK so I think I for sure have figured things out this time, I double checked the Vertical and Horizontal Oscillator tubes and the Vertical Oscillator tube was one of the tubes that was missing in this set when I got it, and so I installed a
NOS Sylvania 6SN7GTB tube I had in my tube stash, which without realizing it should of been a 6SN7GT tube, because I didn't realize until just now that the 6SN7GTB tube is NOT the same as a 6SN7GT tube, the heater is Different and a few other differences as well, so I think that if I can get a new 6SN7GT tube installed in place of the 6SN7GTB I had installed in the TV that might fix my problem.

Unfortunately the 6SN7GT tube is over $20 a pop and I don't have that kind of money to throw around right now... :sigh: :thumbsdn:

OK so I had pulled the 6BG6 Tube out of the circuit and the current draw definitely fell quite a bit, but only down to about 160 watts which is what this TV is rated at when its running correctly which means something is still drawing excessive current yet in the set, but not sure what, as like I said all of the capacitors are brand new so the capacitors can't be the problem, the power transformer isn't the problem, the filter choke isn't the problem (i had confirmed from looking at the schematic that I had the filter choke wired up wrong which after I rewired it correctly, fixed the arcing problem with the 5U4 Tube).

So as of right now I've basically troubleshot and repaired everything that could of possibly been causing issues with this set.
The only other issues that could be causing problems in this set is the Vertical or Horizontal Output Transformers or the Flyback Transformer.

The 6SN7gtb differs only in having controlled heater warmup time, useful in series-string applications. Makes no difference in your application. Any 6SN7 is fine. 'GT' refers only to bulb style. The 'B' is the heater thingy.

It really is best to take your schematic and measure the voltage at the different points, You will find the problem that way. I was working on an amplifier the other day that had no sound after replacing the capacitors and as I traced the power from the capacitors, I found that both resistors that feed the plates of the phase inverter tube were open. Replaced them and had sound. You can't tell by looking, and you can't test parts while they are in the circuit. As for smoke coming out of something, replace the part. I had that happen on my predicata. At the age of the tv's we work on, all capacitors and resistors should be replaced, unless a tube is shorted or really bad... it will serve well enough for testing, you don't have to have a perfect one. Looking forward to seeing a picture of your set working.

If you pull the vertical output tube too and it still draws close to rated power (as I suspect it will) you still need to finish troubleshooting the power supply...Like I said the social coil circuit could be an issue...also depending on where that 390 ohm resistor is in circuit whatever is causing it to smoke is also a likely cause of the overload.

If you pull the vertical output tube too and it still draws close to rated power (as I suspect it will) you still need to finish troubleshooting the power supply...Like I said the social coil circuit could be an issue...also depending on where that 390 ohm resistor is in circuit whatever is causing it to smoke is also a likely cause of the overload.

social coil circuit? :)

R62(390 ohm) is the plate load resistor for the 6V6 audio out(Sams calls it a filter). It supplies voltage from the wiper of the focus coil to the 6V6 plate circuit. This set uses the audio output stage as a voltage dropper, similar to Admiral sets of the time. It's plate voltage(pin 3) should be 205vdc referenced from the cathode(pin 8). Confusing as all get-out to troubleshoot. As mentioned above, best to follow Sams voltage measurement chart to isolate the problem area.

social coil circuit? :)

R62(390 ohm) is the plate load resistor for the 6V6 audio out(Sams calls it a filter). It supplies voltage from the wiper of the focus coil to the 6V6 plate circuit. This set uses the audio output stage as a voltage dropper, similar to Admiral sets of the time. It's plate voltage(pin 3) should be 205vdc referenced from the cathode(pin 8). Confusing as all get-out to troubleshoot. As mentioned above, best to follow Sams voltage measurement chart to isolate the problem area.

Focus coil.

My smart-ass-phone has an overly aggressive autocorrect baked into it's typing utility and it likes to substitute different words for correctly spelled ones when it thinks I didn't use the right one in sentence context...it drives me nuts sometimes, and is even worse for brand name that were gone before my generation and TV service lingo that is otherwise dead.
There are also times it will botch a word in messages to friends and I'll retype the word to make it make sense and it will change it when I push send.... infuriating.

My smart-ass-phone has an overly aggressive autocorrect baked into it's typing utility and it likes to substitute different words for correctly spelled ones when it thinks I didn't use the right one in sentence context...it drives me nuts sometimes, and is even worse for brand name that were gone before my generation and TV service lingo that is otherwise dead.
There are also times it will botch a word in messages to friends and I'll retype the word to make it make sense and it will change it when I push send.... infuriating.

I also have issues with spell checker on my phone, although not nearly as bad as yours, and I agree it's infuriating.

I'll take a look at some more voltages.

OK so this is weird but going across pins 3 and 6 on the 6T8 tube on the TV there is a 30 Ohm dogbone resistor that doesn't show up anywhere on the sams and it measures open which might be part of the reason why this TV has no audio as the 6T8 in this TV functions as the Phase Inverter for the 6V6 tube as well as the Audio Frequency Amplifier and the Ratio Detector Tube, and that dog bone resistor looks factory (which I know sometimes there were little changes made to these old electronics at the factory that weren't always put into the sams because they were done after the Sams were made.)

The other resistors on the 6T8 Tube which goes across pins 2 and 6 (which are the plates of the tube) measure nearly spot on.

so that open 30 Ohm dog bone resistor might be part of the reason why I have no audio.

As for the voltage and resistance readings on the tube sockets, the resistance readings on the 5U4 tube are are a little high, pins 2 and 8 which should measure around 22k ohms measures around 32k ohms and then pins 4 and 6 should measure around 68 Ohms but instead measure around 72 ohms.

That measurement was taken without the tube in the socket and the set powered off.

Don't worry about the 6T8, it has no bearing on your power supply issue and in fact you can remove it from it's socket if it's bothering you. So did you measure the voltages on the 6V6 audio output tube?

By the late 40s some pF range capacitors were made on tubular ceramic forms and color coded....they look just like dogbone resistors but really are dogbone capacitors....If it's presence bothers you check the schematic for capacitors connected in the way it is.

By the late 40s some pF range capacitors were made on tubular ceramic forms and color coded....they look just like dogbone resistors but really are dogbone capacitors....If it's presence bothers you check the schematic for capacitors connected in the way it is.

Likely the 3 uuf cap shown between pin 3 and ground....I suspect that pin 6 was used as a tie point.

jr

Don't worry about the 6T8, it has no bearing on your power supply issue and in fact you can remove it from it's socket if it's bothering you. So did you measure the voltages on the 6V6 audio output tube?

No, I didn't yet.

But I did figure out that pretty much all the resistors in the audio circuit that are associated with the 6V6 and the 6T8 tube are all measuring bad (either way high or open), also the 6,000 ohm 10% 20 Watt wirewound resistor that's part of the HV section is measuring open as well in the Sams its called the Damper Filter-Wirewound, which might be why I'm not getting any HV and also might be part of what's causing the TV to motorboat.

Likely the 3 uuf cap shown between pin 3 and ground....I suspect that pin 6 was used as a tie point.

jr

Yep that's what it was, and it measures within tolerance so I'm leaving it alone.

But all the resistors around it are all out of tolerance or measure open, so they're all getting replaced.

No, I didn't yet.

But I did figure out that pretty much all the resistors in the audio circuit that are associated with the 6V6 and the 6T8 tube are all measuring bad (either way high or open), also the 6,000 ohm 10% 20 Watt wirewound resistor that's part of the HV section is measuring open as well in the Sams its called the Damper Filter-Wirewound, which might be why I'm not getting any HV and also might be part of what's causing the TV to motorboat.

You reported a few posts back that you had a raster, before R62 smoked, so at that point you had HV. All I can say is that there's been a whole lot of smoking going on. ;)

But all the resistors around it are all out of tolerance or measure open, so they're all getting replaced.

Do you check all of the new resistors before you do the replacement... Once in a while a new resistor will be bad or mis-labeled. It is also interesting to recheck the old resistors after removal, to verify your diagnosis.

jr

Do you check all of the new resistors before you do the replacement... Once in a while a new resistor will be bad or mis-labeled. It is also interesting to recheck the old resistors after removal, to verify your diagnosis.

jr

Yes to both, my new resistors tested within spec (they are 5% tolerance resistors) and the old resistors tested way out of spec and or open, and that is the case with almost all of the resistors in this TV it seems and I'm going to have to order some resistors as well because there were some resistor values in the set that I didn't have in my resistor stash like 180k Ohm, 2.2M Ohm, etc.

Most of the resistors in the set I have already fortunately, just a few oddball values that I don't have in my stash I'm gonna have to order.

Here's a couple of the capacitors that were inside the TV some Cornell-Dubilier "Tiny Chief" Capacitors! :scratch2: :lmao:

Well I think as far as trying to get this thing going completely goes, I'm just going to replace all of the open and out of tolerance resistors in each circuit one circuit at a time and test the TV out after each section is done to see what the TV is doing after each section is done, that way if I get the TV to give a raster and what not midway through then I'll know by what sections I just completed replacing the resistors in that those sections were what was responsible for the TV's issues and I'll know that more than likely the rest of the resistors that I hadn't touched yet by that point will more than likely be fine to leave in place (unless they are 5% or 10% tolerance resistors which then in that case I would just replace those because of the fact that those tighter tolerance resistors are a little more important to the circuit's functionality than the 20% tolerance resistor are).

I just put in a large order of Resistors to Mouser of all of the Resistors that I needed that to replace in the TV that I didn't already have in my stash, and it only cost me $22 and some change including 2 day shipping through FedEx. I really stocked up and got 20 of each one of the resistors I needed that I didn't already have in my stash, and that way most of the resistors worked out to be less than 10 cents a piece with some being less than 5 cents a piece.:thmbsp::yes:

OK, so I figured out the mystery of the model number of this set and the one like mine that was in another thread on here.

Sam's DID actually cover this set, in Set 173 Folder 10, the actual model of this set is the Philharmonic Model 820! The exta zero was a typo on the model no. sticker and if you look carefully at the model number sticker the extra zero is actually crossed out, with a felt tipped marker.

So what this TV is actually is a Philharmonic Model 820 TV that was made by Meck Industries of Plymouth, Indiana.

So if anyone has a copy of Sam's 173 folder 10 that they could scan and upload that would be most helpful.

Also a little update on the repair process, I completely rebuilt the audio circuit in the TV and part of the sweep circuitry as far as replacing resistors go, and I'm still getting current draw in excess of 191 watts, and no vertical or horizontal or high voltage still, which I think I have narrowed my issue down to a bad 5U4 tube, which I think if I can just get a fresh 5U4G tube installed in the TV (instead of the questionable ones I have currently that were all redplated or close to redplated when they were ran when the TV had the shorted capacitors in it), I think the TV will start running fine.

The reason why I'm thinking this is because if none of the 5U4 tubes I have currently are strong enough to get the horizontal and vertical oscillators running then that would explain the excessive current draw, because as I understand it, if your vertical and horizontal oscillators aren't running then the TV is going to draw Excessive amounts of current because the vertical and horizontal oscillators when they run help to get the current draw down (at least that's how Shango has always explained it whenever he's worked on sets like this that have had excessive current draw.)

I guess I'll just have to test my theory and buy a NOS 5U4G tube from AES or one of the other tube outfits online.

Yikes, I didn't realize how much 5U4 tubes are going for! :eek: :yikes:

It seems I won't be getting a 5U4 tube for under $20 seeing as they go for between $25-$1,100 a pop! :sigh:

I've had sets that with dead sweep oscillators and the outputs never drew enough to redplate or arc the rect.

I find my 5U4s for $10 a pop or cheaper at swapmeets.... Another option is to make a solid state 5U4 to with some silicon diodes.

I've had sets that with dead sweep oscillators and the outputs never drew enough to redplate or arc the HV rect.

I find my 5U4s for $10 a pop or cheaper at swapmeets.... Another option is to make a solid state 5U4 to with some silicon diodes.

I would like to try and keep this TV as original as possible since this is a rare early TV Set.

I'll keep checking around for cheaper 5U4G tubes.

Also don't you mean Low Voltage Rectifier? The 5U4 is the Low Voltage Rectifier, not the High Voltage Rectifier. :nono:

The reason why I'm thinking this is because if none of the 5U4 tubes I have currently are strong enough to get the horizontal and vertical oscillators running then that would explain the excessive current draw, because as I understand it, if your vertical and horizontal oscillators aren't running then the TV is going to draw Excessive amounts of current because the vertical and horizontal oscillators when they run help to get the current draw down (at least that's how Shango has always explained it whenever he's worked on sets like this that have had excessive current draw.)

I guess I'll just have to test my theory and buy a NOS 5U4G tube from AES or one of the other tube outfits online.

I guess you could also test that theory by pulling your vertical and horizontal output tubes and seeing if your current draw decreases substantially? I think it's highly unlikely that several 5U4's don't have enough snuff to power the circuits. This company has new 5U4GB for $12. Why not keep the rarer 5U4G's for after you get all the bugs out? http://www.abcvacuumtubes.com/vacuumtubes_tubelist.html

I guess you could also test that theory by pulling your vertical and horizontal output tubes and seeing if your current draw decreases substantially? I think it's highly unlikely that several 5U4's don't have enough snuff to power the circuits. This company has new 5U4GB for $12. Why not keep the rarer 5U4G's for after you get all the bugs out? http://www.abcvacuumtubes.com/vacuumtubes_tubelist.html

Well you have to remember that before I got the bugs worked out of the power supply I did :whip: most of those tubes pretty hard (to borrow InItForFun's words) .

Also when I pulled the Vertical and Horizontal output tubes the current draw dropped significantly from 194 Watts to 149 watts, so I think maybe the 5U4 is probably part of the problem, unless there's something else that I'm missing... :scratch2:

So an update, I do have HV and the Horizontal Oscillator is running again, and I think the vertical maybe running again as well, but nothing on the picture tube yet, (I flipped the TV on its side and turned it on and I heard the distintive high voltage buzz and I didn't hear that before).

Also something is still smoking R62 yet, but I think I figured it out, I think it might be R31 which is supposed to be a 27K Ohm 4 Watt resistor (2 56K Ohm 2 watt resistors in Parallel), which are out of tolerance as it only measures at 20k Ohms, that's the only thing I can think of that could be causing my R62 to smoke as that's the only other thing in the path of R62 in the circuit (I even traced it out on the schematic and nothing else was in the path of R62 that I saw of that could be causing R62 to smoke, unless there's something wrong with my 6AC7 tube that's causing it to smoke.

OK so here's a video of what its doing currently.

Just follow the link below and it should take you to the video.

https://photos.google.com/photo/AF1QipNgxe69zcCBpMf4d9lU-94kA2-sTDUuRGgsqv7t

Do you by chance have in your possession a working oscilloscope and the ability to look at the horizontal and vertical oscillator waveforms?