the 6x5 rectifier is a full wave rectifier so im wondering if this tube goes bad can it be replaced with a resistor for the heater if its in a series string set and placing 2 diodes in place. this tube is from a teletone tv 208 and it also has a 25z6 positive i think half wave and i know 1 diode can be used in that place with IIRC a 50 ohm resistor for the heater. please correct me if im wrong.

I would leave the tube in place, and disconnect the plates, and bypass it with a pair of diodes, maybe with some series resistance added to each one. This way--the tube is still there--and LOOKS like it is working--but is bypassed.

I drew a diagram of that very thing for a Zenith radio.

6X5 in a Teletone 208? where? I don't see it on the schematic:

http://www.earlytelevision.org/pdf/Tele-Tone-TV-208-Sams-90-11.pdf

:scratch2:
jr

Yes teletone 208 but the schematic shows a ballast tube in place of the 6x5 is that I have on this set. Maybe the schematic is an early one with the ballast and mine a later.

Yes teletone 208 but the schematic shows a ballast tube in place of the 6x5 is that I have on this set. Maybe the schematic is an early one with the ballast and mine a later.

Possibly the other way around! The later production set probably uses the ballast tube. :scratch2:

Timmy most have a very early production set, 1st run tv-208's were a tv-149 in the suitcase housing. The tv-149 does have the 6X5 in the circuit. All the best, Tom

Yes teletone 208 but the schematic shows a ballast tube in place of the 6x5 is that I have on this set. Maybe the schematic is an early one with the ballast and mine a later.

Interesting! Does the set work with a 6X5 in that position? :scratch2:

jr

If you want to replace the 6X5 (the easy way) with a solid state replacement here is a link to one that you just plug in.

http://www.tedweber.com/wx5

Trouble with those tube's is that they are known for heater to cathode shorts, and when they short it takes out the power transformer. Also Using diodes and resistors should work as well, but you might want to leave the filament in circuit for appearance. Not sure what value resistors are needed as I would assume it depends on the current draw of the radio.

Timmy most have a very early production set, 1st run tv-208's were a tv-149 in the suitcase housing. The tv-149 does have the 6X5 in the circuit. All the best, Tom

Wow! How did they make that fit? Never have seen one... could you post a few pictures of this rare beast?

jr

Ok jr tech I was not very clear on my comment. 1st run 208 used the 149 circuits, 2ed run and later use the circuits you see in Riders and Sams. Hope I made myself more clear on this. I worked on 1 or 2 of run 1 tv-208 but don't own 1 do own a run 2 set. All the best,Tom

The 6x5 is in the exact spot where the other run chassis has the ballast. So I'll have to keep in mind that these tubes are known for heater cathode shorts and there is no power transformer to worry about cooking in the event the tube goes bad. What ohms would be ideal to replace the heater loads on the 25z6 and 6x5 tubes, would 15 ohms 10 watt for the 6x5 and 50 ohms 10 watt for the 25z6 be close ?

Not real close... R=E/I

for the 6X5, I get R= 6.3 volt / 0.6 amp. so R = 10.5 ohms. 15 ohms is a little high, but with todays higher power line voltages will likely work ok.

for the 25Z6 I get R= 25 volt / O.3 amp , so R = 83 ohms. I would not use a 50 ohm resistor there.

10 watt resistors should be adequate.

jr

Well ok but again with the higher line voltages I may try a 100 ohm resistor should I need to for the 25z6 . So I guess it's safe to say that any 25 volt tube that resistance should apply to all. What's odd about this teletone is the schematic for the tv208 is identical to the set I have but there is a lot that's different between the SAMs and what I have . Early television only has the SAMs I have but clearly it is very different , the ballast I don't have and the amount of power supply caps, I only have half the caps that the SAMs shows so there must be an early and late and the tv 149 is totally different then what I have which is what the SAMs shows from early television.

Could somebody post a schematic of the circuit area where the 6X5 is used?

Looks like you could use an adapter to go from an octal socket to a 7 pin and use a 6X4.

Could somebody post a schematic of the circuit area where the 6X5 is used?

Not sure anyone has one but the picture of the set in the SAMs under teletone tv208 in early television is what I have but like I said it's clearly different. I would like to see the right schematic for this set too.

Could somebody post a schematic of the circuit area where the 6X5 is used?

Well if they did use the circuit of the TV-149 in the 208, it should be something like this:

http://www.earlytelevision.org/pdf/Tele-Tone-TV149-Sams-56-22.pdf

Perhaps Timmy could trace out the circuit around the 6X5 and 25Z6 and draw a schematic showing how the power supply is wired. Again I ask, does the set actually work or at least do the filaments light up with the 6X5 installed?

jr

Well if they did use the circuit of the TV-149 in the 208, it should be something like this:

http://www.earlytelevision.org/pdf/Tele-Tone-TV149-Sams-56-22.pdf

Perhaps Timmy could trace out the circuit around the 6X5 and 25Z6 and draw a schematic showing how the power supply is wired. Again I ask, does the set actually work or at least do the filaments light up with the 6X5 installed?

jr

No it's not working yet I'm in the process of recapping so if there are any problems later I'm sure I won't be able to rely on the schematic that's out there now. I was just looking into these tubes because they are the source of b+ along with one selenium which will be replaced with a 1n4007 diode later. And now he reign that the 6x5 is known for cathode shorts so there is nothing like a reliable silicon diode and maybe leave the tube in for show, long as it still lights. This is just in case later on I will have this info to do if I could not obtain these tubes. Kind of a backup plan, alternate.

I was puzzled over the references to the 6X5 being "used as a ballast". Does that mean the diodes are paralleled and used in lieu of a nichrome wire dropper tube? :saywhat:

I was puzzled over the references to the 6X5 being "used as a ballast". Does that mean the diodes are paralleled and used in lieu of a nichrome wire dropper tube? :saywhat:

I don't think that anybody indicated that the tube was actually used as a ballast, only that it occupied the same socket location as was occupied by the ballast in later sets. :scratch2:
I would love to see a schematic for the set that Timmy has, but very likely the schematic is close/same as that of the TV-149, which has an 80 ohm dropping resistor in the heater circuit and also a selenium rectifer as well as the 25Z6 and 6X5.

jr

Well I looked at the tv149 schematic and it's different as it has 2 - 25z6 tubes and mine only one so I can't go by that schematic should I need to.

No it's not working yet I'm in the process of recapping so if there are any problems later I'm sure I won't be able to rely on the schematic that's out there now.

:scratch2: I hope this means your intentions are to get this set working perfectly in it's original configuration , and then when it's working perfectly as designed you will consider any modifications ? Restored correctly , the circuit will function as it's manufacturer intended , and that should be the baseline from where any modifications to the power supply are considered .

Myself , I'd restore it to what I'd call 99.5% original , I'd leave all the tube circuits alone modification wise and use a modern diode (with resistor) in place of the Selenium (which would remain on the chassis but with both of it's wires run to a terminal strip)

As you've already noted , this set has no power transformer to roast , so there really is no need to play "hot potato" with the 6X5 here .

:scratch2: I hope this means your intentions are to get this set working perfectly in it's original configuration , and then when it's working perfectly as designed you will consider any modifications ? Restored correctly , the circuit will function as it's manufacturer intended , and that should be the baseline from where any modifications to the power supply are considered .

Myself , I'd restore it to what I'd call 99.5% original , I'd leave all the tube circuits alone modification wise and use a modern diode (with resistor) in place of the Selenium (which would remain on the chassis but with both of it's wires run to a terminal strip)

As you've already noted , this set has no power transformer to roast , so there really is no need to play "hot potato" with the 6X5 here .
Yes I always restore what was there originally including tubes however if a specific tube was not available I would like another option in place to replace a tube if possible which in this case I can do so if needed. And it's possible to just use a modern diode without a resistor because what I sometimes do is the resistor in series with ac I will up the ohms for both the diode, increased voltage which is only a few volts and also the increase in line voltage which seems to vary from area to area. The aim here for me is to always get a set working the way it was intended and what annoys me because it always has to be perfect while I don't consider myself a perfectionist , I want it right, even down to the flow of solder, it don't look right I do it again. :yes:

Well I looked at the tv149 schematic and it's different as it has 2 - 25z6 tubes and mine only one so I can't go by that schematic should I need to.

The TV-149 schematic that I linked to shows only one 25Z6 but each section of it is drawn as a separate 1/2 tube. Is that what you are counting as two tubes?

jr

Yes you are right it is shown in 2 sections but one tube but this is definitely not the same schematic for the set I have since the 149 is one a piece chassis and mine is a 2 piece chassis. Even the power supply caps are different.

Yes you are right it is shown in 2 sections but one tube but this is definitely not the same schematic for the set I have since the 149 is one a piece chassis and mine is a 2 piece chassis. Even the power supply caps are different.
Just for S&G's, look up the schematic for the early model, Hallicrafters T54. The power supply circuit looks very similar, including the resistor values.
The Sams for one of those models, shows the electrolytics drawn with the wrong polarity. :thumbsdn:
BTW, what's so bad with the newer issue 6X5's. I'd leave it as-is. :scratch2:

I really need the right schematic because there are resistors that don't have colors and I need to know the right value, they are bad.

Could you draw out a schematic of how the components in the circuit are connected and post it here? Perhaps we can back-enginner the circuit and figure out what the resistor values should be. :scratch2:

jr

I'm still looking desperately for what I believe is the right SAMs for a teletone 208 r because the 208 and the 208 tr have a ballast but mine don't. There are 2 SAMs that I know of, 90-11 and 95-6 both are not mine but I don't know the SAMs number for the 208r . Mine has the round plug that connects both chassis together like the tr and the tr also has the round plug. The 208 has the square plug and a ballast, the 208 tr has the round plug and a ballast, the 208 has the round plug and NO ballast. Does anyone have this print ?

There is no separate listing for the 208R, only the TV208 and the TV208TR. Have you looked at both Sams? If not, I should have both.

I've got a pristine folder 95-6 if you still need it.

Cheers,

I didn't actually look at the 208 tr but the 208 I did . I read a post on antique radio I think it was and someone there had the same problem with or without the ballast. Well maybe it is the 208 tr until I could see some of it I will know. If someone could show me a part of it I will know if it's the one, thanks

Your set is probably wired for the ballast. I've seen it a bunch of times some tubes and or ballasts fail, the owner pulls the tubes to test looses them and years later some dope randomly sticks any old tubes in the sockets hoping to make it look better or work. Pull the chassis and carefully compare to both versions.

This has a 6x5 in the place where the ballast would be and it has 2 resistors wired in and they are old original and they are the ones that are in the ballast in the other set that has one. Besides mine has 2 12sn7 for vert amp and multi the other 208 has a 6sl7 . But overall I recapped it and has great sound and picture from the little I can see the vert height or size there is only one pot is maxed and it's only about 2 inches it won't fill the screen. So I need the SAMs to check voltages to see what's going on in the verticle, it would help as now Im done aside from checking resistors which I did changed a few in the verticle and it improved very little.

It's vertical!

Well all the crazy things about these teletone tvs I had pulled a 6sl7 out of the vert amp but the tube lineup on the cabinet showed a 12sn7 belongs there so again there are so many differences with these because I put the 6sl7 back in and the verticle is fixed. So maybe it is infact a 208tr but without the ballast.

Does anyone know if there is a retrace mod out there for the teletone 208 tr. most pin 3 of the 7jp4 go to ground but the teletone goes to DC restoration.

I need to find the values for the Micas in the verticle and the 208 don't show what I have and the 149 shows Micas but Alittle different wiring and shows 5000 pf but I can't be sure if this is the correct value or not. Maybe the 208tr is the one I'm looking for, would anyone post the 208tr or sell me a print but I would like to know if this is what I need for sure.

The value of the micas are most likely right. If you don't know how to read them here are 2 sites you can get info on how to read them. http://radioremembered.org/capcode.htm and http:www.tpub.com/neets/book2/3g.htm there were 2 other sites but they are now porno! All the best, Tom

Is there a way I can get some idea what the value is on this resistor which the center seems to have got hot and the color is gone. The first is brown and the last looks like it was brown but the middle I just don't know. The end dot looks to have a spec of brown left to suggest, brown, blank, brown.

What does the schematic identify it as?

.

What does the schematic identify it as?

.
That's just the problem, there is no schematic due to last minute changes in production back in the day and comparing close schematics don't help.

Timmy, are you sure it is a resistor? I've never seen a mica mold resistor. If this is your TELE-TONE, determine what tube element the part ties to on both ends. Me thinks it is a cap. All the best,Tom

Me thinks it is a cap. That's what I was alluding to in my post. If timmy could have found where he pulled it from on a schematic, he would have discovered that.

.

Yes there are resistors that look like Micas and this resistor is between the 6x5 and 25z6 for the negative side of B+ . I found a site that shows the type resistor I have and it says this type resistor that has 3 color dots they are saying to read them like any other resistor like all the others with colors so I came up with anywhere between 100 ohms and 190 ohms because the first color is brown , next unknown, and a spec of brown on the third so I figured I would go between and put a 150 ohm because the original was burned in the middle measuring 1.2k ohms and I have a small issue with horiz and vert not filling top and bottom so if this works I'm good to go. Oh and yes it's the dreaded teletone that so I read many people having many problems with this particular set.

Aha! http://www.antiqueradios.com/forums/viewtopic.php?p=1762645#p1762645

I probably knew that sometime in the past, but haven't worked on anything with them in a long time...

.

So I guess the only way really to tell if it's a cap or resistor then it would have to maybe depend where in the circuit it's placed. :scratch2: :smoke:

Yes there are resistors that look like Micas and this resistor is between the 6x5 and 25z6 for the negative side of B+ . I found a site that shows the type resistor I have and it says this type resistor that has 3 color dots they are saying to read them like any other resistor like all the others with colors so I came up with anywhere between 100 ohms and 190 ohms because the first color is brown , next unknown, and a spec of brown on the third so I figured I would go between and put a 150 ohm because the original was burned in the middle measuring 1.2k ohms and I have a small issue with horiz and vert not filling top and bottom so if this works I'm good to go. Oh and yes it's the dreaded teletone that so I read many people having many problems with this particular set.
The resistor in the negative source, between the two 30mf caps is a 1.2k 1w wire wound resistor. Red turns brown real easy with heat.
I've seen that type of Micamold resistor and most were tiny wire wounds.
WW resistors seldom change value, especially that much. They, most of the time, just open.

The resistor in the negative source, between the two 30mf caps is a 1.2k 1w wire wound resistor. Red turns brown real easy with heat.
I've seen that type of Micamold resistor and most were tiny wire wounds.
WW resistors seldom change value, especially that much. They, most of the time, just open.

Problem is all the teletone schematics I looked at does not even come close to what I have here and this resistor don't look WW , it's flat . and mine is wired completely different then that of all the schematics out there. Some have ballast some don't some have 6x5 some don't. This resistor is not between 2 caps I already seen that in the schematic , it is so different.

Ok well I have a 1k WW in there now so I'll leave it and assume it's right, I broke the old resistor in half and it's WW so maybe that's the right one. And I do agree that WW usually don't change but rather open.

Ok well I have a 1k WW in there now so I'll leave it and assume it's right, I broke the old resistor in half and it's WW so maybe that's the right one. And I do agree that WW usually don't change but rather open.
Maybe the Sams doesn't show it as a wire wound, but the original Tele-tone print shows 1.2K WW resistor in the B-circuit.

With a WW resistor, often you can break it open and find a section that has continuity, and extrapolate the original value.
E.g., if half the winding is good and shows 500 ohms, the original will be 1000 ohms. Or if a third of the winding is good and shows 500 ohms, the original will be 1500 ohms. Etc.

Since WWs don't change value much, this method gives a pretty reliable approximation, considering standard +/- tolerances.

Still working on this schematic free set, 208, 208tr, 149, schematics don't match my set but anyway I have good sound and picture but cannot find any reason why I can't get full size top and bottom if I try to stretch by the pot the pic washes out Alittle and gets a line across the top so I back it down a bit and it just simply looks like everything is broadcast in wide screen. The bottom fills but not the top. All the caps, hv and power supply were replaced. Can't find any bad resistors.

Do all of the voltages across the circuit measure as specified?

Can't compair or I would, don't have a schematic for this one, to many production changes back in the day and these changes were never published. Figured there was something I may be over looking for the basic causes of not enough of vert size.

timmy - It often helps to keep your complete restoration progress for a TV or radio in ONE thread. It makes it easier for all to follow, that way we can often see when someone makes a mistake earlier that may have caused other problems later on. I'm not sure how many threads you have already on this Teletone, but it must be 5 or 6 by now. Not many people want to keep tracking your other threads to see what changes or repairs have already occurred, that may have indirectly caused the current problem.

.

Well there was no specific problem that caused this and there may be 3 threads on the same set as not to mix up to much to do with this crazy set. it was mostly finding the right schematic which don't exist so I'm on my own without any voltages to go by.

Still working on this schematic free set, 208, 208tr, 149, schematics don't match my set but anyway --

A picture -- cabinet and chassis -- would help to identify the set.

From reading the above, one does not know enough about the set to make a suggestion.

James

Actually you do have 5 related threads started on this set. Had the same problem following your Pilot TV story that you started 7 separate but related threads about.

Please take the advice. If you make it difficult for people to follow along to help you, they will give up. Often one problem will lead to another, and it's really helpful to know all work that has been done so far.

.

Ok, recapped, that's it, and it's I think 1948 teletone leatherette without the cover, 208 but what 208 no one knows. Comparing to the 149, 208, 208tr, none help this set at all as there are so many differences from mine to all the schematics out there. I'll figure it out, thanks.

Merged the several threads about this set into one. In the future, only create ONE thread per topic, please.

Ok, recapped, that's it, and it's I think 1948 teletone leatherette without the cover, 208 but what 208 no one knows. Comparing to the 149, 208, 208tr, none help this set at all as there are so many differences from mine to all the schematics out there. I'll figure it out, thanks.

I'd imagine that they kept the vertical stage fairly standard across models...Trace your vertical stage and compare it to the schematics of all listed models that use similar vertical stage tubes to yours...If the vertical stage matches (or is very close), and uses similar B+ voltages, then all the tube base voltages on the vert section of the schematic should be used as references and compared to those in the set.

I'd imagine that they kept the vertical stage fairly standard across models...Trace your vertical stage and compare it to the schematics of all listed models that use similar vertical stage tubes to yours...If the vertical stage matches (or is very close), and uses similar B+ voltages, then all the tube base voltages on the vert section of the schematic should be used as references and compared to those in the set.
What's kind of odd is I compared the teletone tv149 voltages and the tv208 and they don't come close and the tv208tr voltages I don't have as I only have the schematic not the resistance and voltage charts. This verticle problem is minor I'm sure because everything is working fine except turning the size pot it stops filling in then gets a white line across the top almost to say it went over some limit. The pot I checked and it's good and also the resistor from the pot to the tube. I have 410vdc at the size pot but don't know if it's the right voltage.