Hello all,

I recently acquired this 1970s Zenith. From what I can gather, the chassis is 25DC56 or 25DC57.

The seller provided video proof of it working prior to being stored in the garage for ~year. There is a slight letterbox burn in on the tube. Hopefully this won't be an issue when playing content.

Currently, I plugged the unit in for the first time and upon turning it on I smelled ozone. It is currently non-responsive. There was no audio present either or else I would suspect the HV circuit.

Does anyone have any experience or item to check on this particular chassis before I begin replacing capacitors in the power supply section?

Congrats on your Avanti. That is the best chassis ever built by anyone.First thing is you MUST MUST check the HV caps. IIRC there are 2 on the flyback
& 3 more under the chassis. They are marked 22-5001 & all the same.
If they are white you MUST change them before anything else. If they
are orange they are OK to leave in. You must use the right type for
replacements or they WILL short out.
After thats done you can trouble shoot it. Its very easy to repair at that point.
To access under chassis there are 2 ways.
1) carefully flip set on its side & remove bottom plate.
2) Remove 4 heavy bolts from bottom of chassis. Place a heavy box behind
the set at chassis height. Loosen wire bundles & flip chassis on its side
on top of the box ( my favorite !).

I loved fixing these but even though we were a major Zenith dealer they
were bullet proof so didnt see many. If it werent for the HV cap problem
they were near 100% reliable for ever. CRT's also as good as you could get.
Never saw a weak one in the olden days.

73 Zeno:smoke:
LFOD !

Hey Zeno,

Thank you! I'm glad to hear it as a good chassis as the looks alone are what made me go after it.

I had a peak and the two caps on the flyback are indeed white with the wording "Special". Do you have a recommended replacement?

And thank you for the disassembly tips! Honestly, with everything being a connection point it looks very easy to get at and service.

As for replacement I think the old 22-5001 caps have been bought up.
I am sure someone will pipe in with the proper replacements. They have to handle the 1 KV spikes on the hoz output plus the 130 VDC.

Reason this is important is the HV runs at 30 KV. Every cap that opens
adds apx 2KV. If all 5 open you are over 40KV HV. I had one where 4 were open & that set sent lightning bolts from from the HV. It will work with a few bad but it will slowly eat up the HV tripler, CRT socket, HV divider when used & Hoz out. The ozone is a sure symptom of trouble.
BTW you may hear about the 4 lead cap. Its the same idea but only on newer chassii.

Hey Zeno,

Thank you! I'm glad to hear it as a good chassis as the looks alone are what made me go after it.

I had a peak and the two caps on the flyback are indeed white with the wording "Special". Do you have a recommended replacement?

And thank you for the disassembly tips! Honestly, with everything being a connection point it looks very easy to get at and service.

As for replacement I think the old 22-5001 caps have been bought up.
I am sure someone will pipe in with the proper replacements. They have to handle the 1 KV spikes on the hoz output plus the 130 VDC.

Reason this is important is the HV runs at 30 KV. Every cap that opens
adds apx 2KV. If all 5 open you are over 40KV HV. I had one where 4 were open & that set sent lightning bolts from from the HV. It will work with a few bad but it will slowly eat up the HV tripler, CRT socket, HV divider when used & Hoz out. The ozone is a sure symptom of trouble.
BTW you may hear about the 4 lead cap. Its the same idea but only on newer chassii.

I managed to pick up 4 NOS Zenith 22-5001 caps on Epay. It looks like that is the last of them. I grabbed a 22-5001 Zenith equivalent by Associates. I figure this will be better than what is current in the system.

As much as I'd enjoy having a Tesla coil, inside of a TV is not where I would want it. Based on the scorch marks I am seeing on the socket and elsewhere, it would seem that your analysis is correct. I'll report back once I get these new caps swapped in.

Thanks again for your help! :thmbsp:

Once in a while the motor run cap that is used to make the voltage regulating power transformer regulate will fail. IIRC when it does the breaker on the chassis will trip. I've had 5 CCIIs and it's never happened to me, but I've seen atleast 3 cases on these forums...So it's something to be aware of.

.....As much as I'd enjoy having a Tesla coil, inside of a TV is not where I would want it. Based on the scorch marks I am seeing on the socket and elsewhere, it would seem that your analysis is correct....


A point to remember here is that if the socket is scorched, it very well could continue to arc even when the new caps are installed and bring the voltage back down to where it's supposed to be. The scorching produces "Carbon Tracks" which could allow the arc to happen at the lower proper voltage (better conductivity through the burnt carbon VS a virgin socket)

I figure you likely already know this, but in case you didn't, it's worth mentioning......

Once in a while the motor run cap that is used to make the voltage regulating power transformer regulate will fail. IIRC when it does the breaker on the chassis will trip. I've had 5 CCIIs and it's never happened to me, but I've seen atleast 3 cases on these forums...So it's something to be aware of.

I will make sure to keep that in mind once I start troubleshooting. I have yet to see an oil capacitor go bad yet.


A point to remember here is that if the socket is scorched, it very well could continue to arc even when the new caps are installed and bring the voltage back down to where it's supposed to be. The scorching produces "Carbon Tracks" which could allow the arc to happen at the lower proper voltage (better conductivity through the burnt carbon VS a virgin socket)

I figure you likely already know this, but in case you didn't, it's worth mentioning......

I had known of it, but didn't consider it. Thank you for the tip. I have attached pictures of what I believe to be from arcing. I am able to scrap it away without issue with my finger so it should clean up nicely. This seems to be a higher hour set, so it could be just use. If it becomes an issue, I may need to source a replacement socket.

Hello all,

I recently acquired this 1970s Zenith. From what I can gather, the chassis is 25DC56 or 25DC57.

The seller provided video proof of it working prior to being stored in the garage for ~year. There is a slight letterbox burn in on the tube. Hopefully this won't be an issue when playing content.

Currently, I plugged the unit in for the first time and upon turning it on I smelled ozone. It is currently non-responsive. There was no audio present either or else I would suspect the HV circuit.

Does anyone have any experience or item to check on this particular chassis before I begin replacing capacitors in the power supply section?

If the TV is not showing a picture after it is turned on, but the sound, pilot lights, etc. operate normally, the problem might be in the deflection circuits; however, since you say there is no sound, and the TV is otherwise dead, the problem may well be in the B+ supply, or perhaps a fuse has blown. If the latter, however, make absolutely certain the problem which caused the blown fuse is corrected before replacing the fuse, otherwise the set will just keep blowing fuses.

You mentioned capacitors in the power supply. These could also cause problems with the B+, as I mentioned; if any caps are shorted, they must be replaced immediately, or else the TV will blow fuses left and right. The TV may still work with leaky capacitors, but I would replace those caps immediately before doing anything else. If you see hum bars or other picture distortion, the problem is being caused by 60-Hz hum getting into the deflection circuits; again, the cure is to replace defective filters or shorted tubes in the deflection systems.


If there is a burn mark on the CRT screen, I cannot see it. The burn must be quite small, or else it is located in a corner of the screen where most people would not see it unless they were looking for it, and I zoomed in on the image to have a closer look at the set; I still could not see any evidence of a letterbox burn mark anywhere on the screen. These marks can appear on older TVs' CRTs if the horizontal or vertical sweep is not working properly; when the vertical sweep failed in CRT sets, and the set owner did not turn down the brightness control immediately, the line across the width of the tube could and often did burn a mark in that area--ruining the tube, of course.

Burn marks at the sides of the CRT screen can also occur if a 16:9 image is viewed on an older TV, since the picture will not fill the screen, as was mentioned. This type of screen damage can also occur in flat-screen HDTVs if a 4:3 image is viewed with the zoom control set incorrectly. However, if a 16:9 image is viewed with the zoom set for 4:3 aspect ratio, black bars will appear at either side of the screen; this can and likely will cause permanent burn marks (from the LEDs or backlight) if the picture is either viewed with excessive brightness or for an extended period of time.

I can only imagine how many flat-panel HDTVs were ruined because the set was either not shut off immediately, or the brightness control was not turned down at once when the sweep failed. IMHO, there should be a fail-safe system in HDTVs which will shut down the set immediately if the sweep fails for any reason. Such a protection system, after all, was built into all analog color TVs to guard against X-ray problems, if the horizontal sweep system produced excessive HV or something went wrong with the HV regulator tube or circuitry.

The black looks like static attracted dust from normal use. Rubbing alcohol should clean it, Goof Off will clean what alcohol misses.

If there is a burn mark on the CRT screen, I cannot see it. The burn must be quite small, or else it is located in a corner of the screen where most people would not see it unless they were looking for it, and I zoomed in on the image to have a closer look at the set; I still could not see any evidence of a letterbox burn mark anywhere on the screen. These marks can appear on older TVs' CRTs if the horizontal or vertical sweep is not working properly; when the vertical sweep failed in CRT sets, and the set owner did not turn down the brightness control immediately, the line across the width of the tube could and often did burn a mark in that area--ruining the tube, of course.

Burn marks at the sides of the CRT screen can also occur if a 16:9 image is viewed on an older TV, since the picture will not fill the screen, as was mentioned. This type of screen damage can also occur in flat-screen HDTVs if a 4:3 image is viewed with the zoom control set incorrectly. However, if a 16:9 image is viewed with the zoom set for 4:3 aspect ratio, black bars will appear at either side of the screen; this can and likely will cause permanent burn marks (from the LEDs or backlight) if the picture is either viewed with excessive brightness or for an extended period of time.

I have attached closer pictures of the screen that hopefully provide a better view of the burn-in.


I just went to fire up the TV to verify that it was indeed still dead, but to my surprise it was not. Upon power up the static audio came in, but I did not hear any HV whine kick in. After about 5 seconds, the breaker blew. Resetting the breaker produced the same results. Due to the age of this unit and my desire to daily drive it, it may just be best to fully recap this system (including the safety caps) and begin troubleshooting afterwards. I'll have to pull the chassis out and make a list.

The black looks like static attracted dust from normal use. Rubbing alcohol should clean it, Goof Off will clean what alcohol misses.

That is good to hear!

Best to recap after you get the HV up

Oil cap. Lift one end & try again. If its bad you will get a raster
but it will pulsate.

Sockets burn inside at focus pin. Almost a Zeniths from the 70's
use the same part but have different lead lengths & connectors.
Dont remember P# but format is 78-####-##.

Cant see the HV area but loosen the tripler & HV divider. Inspect
for cracks, bulging, discoloring etc.

try that
Zeno:smoke:

+1 to what Zeno just said.

Once you get it working one thing I'd absolutely change are all the gray tubular 100uF 50V lytics under chassis. One of my sets had no color on the IIRC right half of the screen because one of those caps leaked electrolyte and rotted a lead off. I think I had another one of those caps fail in something, but don't remember what.

I had restored one of these Avanti sets with a 25DC56 chassis. It had several issues, when I got one fixed, another was found.
The new owner was not a tech, so I had to make sure all the bugs were out.

The 24 volt supply was dead from a burned up 2.2 ohm resistor, so I had HV but no vertical sweep or sound.
It turned out to be a shorted .1 mf 50 volt cap, tubular dark red, that burned up that resistor. You just never know what part is bad until you disconnect everything fed from that source.

Often, 24v feeds thru almost every module, so that if one is removed, the circuit is broken and none get 24v. Generally, small capacitance value electrolytics at low voltages - 10, 50 or 100 volts do not hold up well. I tested EVERY electrolytic capacitor for ESR and found only a few really bad, but I changed all except the large multi section cans, which were good.


Very glad you found those 22-5001 caps! Stay tuned and keep trying, there is lots of Zenith CC experience here.

I’d be weary of that motor cap- unless it explicitly says so, it might contain PCBs. Nasty stuff

Hello all,

Thank you for all of the advice and tips! I have 3 of the 5 22-5001s in. Once I have all 5 and install them I will begin troubleshooting based on your recommendations!

This is going to be a big project, but will be more than worth it in the end.

The main thing is getting the HV up now & a raster. That way
you can be sure the CRT is strong before spending too much $$
on it.
Sounds like the tripler may be bad. Unhook the wire from the flyback
donut to tripler. At the flyback end you should get a nice 3/8 arc
into the air if you put a screwdriver near it. Will also stop tripping
the breaker.

Zeno

Hello all! I apologize for the delay. Got a new job, moved across the country, and now finally have some spare time to put into troubleshooting.

I got the base off and found these items upon inspection. It looks like one the safety capacitors (white) got quite hot at one point.

Also there this blue ferrite disc (choke or inductor?) that is broken in half. I need to get ahold of the schematic to figure out what it is and for.

I am currently working on previously mentioned troubleshooting steps.

Upon lifting the leg of the motor capacitor, I still have the same symptom of audio buzz and then the breaker blowing after a few seconds. There is no filament glow in the tube neck.

Update 1: Upon inspection of the chassis circuit diagram, the blue disc is R324 22 ohm thermistor for the degauss coil.

Update 2: After seeing the 22-5001 scorched on the chassis, I replaced all 3 on the unit with Zenith replacements. Looking at the HV tripler, is this the original unit or is this a replacement unit that combined the focus divider? It is a SCI 7234 "212-139".

Update 3 (closer to the issue): I checked out Q801, 802, 803, and 804 on the Horizontal Output module and they checked out good and within specifications. I replaced the HO module and removed the screws to the Horizontal Output Transistor and the breaker did not blow. The Filament in the neck is glowing. Seems like its either this transistor or the tripler. Will pull the transistor and check it out.

Update 4: I pulled the Horizontal Output transistor Q216 and measured collector to base and collector to emitter for a short. I did not find any.

I reinstalled Q216 and unsoldered the input from the flyback to the tripler. It is still tripping the breaker and there is no high voltage crackle.

According the schematic after Q216 there are multiple capacitor that could have failed and are shorting to ground. I will begin checking these.

Check the damper 103-193 IIRC subs 103-287
That red blob looks like it was the focus diivider got to deal
with that.
If it works with HOT screws out that usually means bad HOT or tripler.
BUT there are huge spikes on the HOT C. May be one of the caps
breaking down but not showing a DC short.

Zeno

Hey Reno,

I'll take a look at that this evening. To be honest, if I can find a tripler that has an internal focus divider I wouldn't mind swapping it out rather than dealing with that orange blob. I remember a forum post listing suitable replacements if I can dig that up.

I hope that something truly failed given the original power on event of a sulfur burning smell; that would make diagnosis much easier.

+1 on Zeno's last reply. In addition to the damper I would also investigate C261 which is just off the collector of the HOT. I'm looking at Sams 1312 and that cap may actually be a "feed thru" It will have a pin on each side of a flange, the flange is grounded, usually soldered to the chassis or a metal bracket. Sams lists this cap as 22-5395 .001 @ 1.2kv

If you are interested, google for a YouTube:
"Troubleshooting the 1973 Zenith 25DC56 Color Television Chassis" by drh4683.
Very good video, methodically troubleshooting the same chassis and circuits you are working with. Breaker popping, he locates a shorted safety cap. There may be a view of C261 in the video. He is also troubleshooting with the Zenith CM manual.

I am working on a 25DC56 and posting in the Solid State sub-forum. I haven't attempted to power my set up yet. I'm waiting on the safety cap subs from Mouser. If any of mine are open, I wouldn't be running it that way for any length of time, and if any of mine are shorted, not going anywhere anyway. So replacing them first is a good initial step, troubleshoot the rest after that.

My tripler, 212-139 is original as is my 63-9012-2 focus divider.

The red blob is your focus divider covered in HV-putty, was a replacement that started to arc. Sams lists 63-9896 as a replacement. I'm not sure about that....

BTW I'm away from my set or I would have checked for C261 and sent a picture.... If it is a "feed thru" it doesn't look like a typical capacitor.

Hey Todd,

That was my first suspect cap. I have actually watched the video you mentioned and picked up a few tips from that. I am also using a Sams and its proven quite handy when identifying chassis components.

C261 is a weird little thing. It is however the last component before my safety cap that got nice and toasty. I'll have to take it out of the circuit and test it.

Should you have any issues getting your safety cap replacements, I have a Zenith 22-5001 OEM replacement and a Associates equivalent left over. (I thought there were 5 safety caps, but I have only seen 3 so far)

I greatly appreciate the help!

It is a feed thru, its located in the bracket that is immediately to the side of the HOT socket. one end is connected to the yellow wire. It looks like a resister with a collar around it.

Not sure how you feel about your past steps but this might be a good time to regroup and repeat and verify some of your work. Zeno's advice is quite sound.

Can you post a picture of the 3 safety caps you replaced?

Have you checked the damper diode?

You can check the feed thru cap with an ohmmeter but that does not rule it out as a problem. It may not be shorted with a DC voltage present but if you put the screws back into the HOT, the horiz circuit will start and the AC voltage there is quite high. From the HOT socket, collector pin, what sort of resistance to ground are you seeing?

NVM, you are correct. I needed to look closer. There are 2, one on the base, the other, you have circled, is the collector.

Usually 2 caps are on the flyback & 3 more under the chassis.
If any got changed to orange ones you may miss them.
Feed thrus are known to go but its rare. I think I had 2 or 3
all on the 13GC10 13" chassis.
I did see a NOS triple at one of the distributors BTW. Try to stay original.
BTW I hope that putty was put on by the owner. If it were a tech
I would fire him. Lucky they didnt see fire trucks !!

Zeno

It is a feed thru, its located in the bracket that is immediately to the side of the HOT socket. one end is connected to the yellow wire. It looks like a resister with a collar around it.

Not sure how you feel about your past steps but this might be a good time to regroup and repeat and verify some of your work. Zeno's advice is quite sound.

Can you post a picture of the 3 safety caps you replaced?

Have you checked the damper diode?

You can check the feed thru cap with an ohmmeter but that does not rule it out as a problem. It may not be shorted with a DC voltage present but if you put the screws back into the HOT, the horiz circuit will start and the AC voltage there is quite high. From the HOT socket, collector pin, what sort of resistance to ground are you seeing?

I will check this this evening and go back through and verify.

Usually 2 caps are on the flyback & 3 more under the chassis.
If any got changed to orange ones you may miss them.
Feed thrus are known to go but its rare. I think I had 2 or 3
all on the 13GC10 13" chassis.
I did see a NOS triple at one of the distributors BTW. Try to stay original.
BTW I hope that putty was put on by the owner. If it were a tech
I would fire him. Lucky they didnt see fire trucks !!

Zeno

I didn't see any other orange ones that looked like my replacements. Looking through the SAMs I only see C268, C267, and C265 listed as 22-5001 capacitors. I replaced the 2 on the flyback and the one right after the HOT. Do you happen to know the designations of the other 2?

I was looking online and had no luck finding a 212-139 tripler for sale. Fingers crossed this one is okay. However, that focus divider is a mess. I do plan on replacing that at least if the tripler turns out okay. This was a one owner set and based on its heavy usage I doubt it was done by the owner.

I went to check HOT collector to ground and sure enough there was continuity. There was also continuity between the HOT collector and emitter. I took the HOT out and rechecked the circuit without it. The collector side of the circuit was no longer grounded.

Long story short my HOT has failed and I was checking continuity for the collector (threads) incorrectly. There is a short from collector to emitter and collector to base. I will be sourcing a replacement.

I have also attached the requested pictures of my 22-5001 caps. They are in for troubleshooting rather than looks at the moment.

Update 1: From a quick glance, the Zenith replacements are all but gone. I was able to find sources for the RCA SK3115, Sylvania ECG165, and NTE165 replacements. Of course OEM is preferred, but is there any pecking order on other brand replacements?

From Zeno the Zenith 212-139 crosses to a 800-791 in the Zenith Replacement line of triplers. I can see the same information. Also crosses to a NTE/ECG 521 if you are willing to stray to a non-Zenith part. In both the 800-791 and the NTE/ECG 521 there is a focus tap that is unused in this application, so you clip the lead and cover it over with silicone.

From everything I can find the original 212-139 was a 6 step tripler, rated at 30KV max, no focus tap. Sams indicates the Focus Divider is 200meg tapped at 40 meg. It appears to me the NTE/ECG 530, Zenith 977-9530, is close. They are also 6 step triplers, rated at 30KV max, with an internal divider, 240meg tapped at 40meg. Sams indicates we should see 25KV at the CRT, and there is no adjustment.

I haven't found any documentation/information this was a recommended replacement for both the tripler and the divider, but I know this was done back in the day.

It would be nice to hear from anyone that has gone down this path. I asked the same question in my thread about a single replacement for both.

Hope this helps, good luck with your set.

Good catch with the HOT. I always had good luck with ECG 165. Be mindful of the insulator and the heatsink compound. The tripler may still be bad, and took out the HOT. You know the the divider has been arcing at some time in the past.....

Due to the state of the focus divider, I am not trusting anything past the HOT.

I didn't realize how hard it is to get a hold of parts for this era of Zenith.
I think I may have to go with a 800-791 tripler and get a hold of a new focus divider. I wasn't able to find the 63-9896, but there is the Zenith 800-616 kit that per the listing is compatible with the 63-9896? I really need to find one of those cross-reference books..

What Sams are you using? I am using the 25DC56 scan from the Sams site and it doesn't appear to mention anything about the focus divider other than it is R361. (not listed in the parts tables)

I picked up 2 HOTs just in case one goes during testing. Is there any specific heatsink compound that is required? I have some used for CPUs; figured that would work just as well.

If you are looking for a Zenith voltage divider, look also at the Sylvania ECG replacement types - the Hi-Div series. An ECG Hi-DIV-3 replaces the 63-9896, 63-9897,63-9898, and the 63-9898-02. Various Mounting positions are possible with the ECG replacements too - unlike the Zenith OEMs.

The Internet archive has the ECG replacement guide from 1989, if you wish to look at the HI-DIV-3 data.

https://archive.org/details/EcgSemiconductorsMasterReplacementGuide1989/page/n469/mode/1up

If you are looking for a Zenith voltage divider, look also at the Sylvania ECG replacement types - the Hi-Div series. An ECG Hi-DIV-3 replaces the 63-9896, 63-9897,63-9898, and the 63-9898-02. Various Mounting positions are possible with the ECG replacements too - unlike the Zenith OEMs.

The Internet archive has the ECG replacement guide from 1989, if you wish to look at the HI-DIV-3 data.

https://archive.org/details/EcgSemiconductorsMasterReplacementGuide1989/page/n469/mode/1up

I was unable to hunt down any of the ECG Hi-Div-3s. However, I was able to find a Zenith 800-616 kit which replaces the 63-9897 and 63-9898-02. Since the ECG Hi-DIV-3 also replaces those and also the 63-9896, its worth a shot thinking that a 63-9897 will work in place 63-9896.

Not sure if this logic works, but given part availability its worth a shot. I've been trying to find specification information on the 63-9897 to compare to the 63-9896.

The 63-9897 is used in the 19EC13 chassis, and is featured in Tekfax 113, available over on World Radio History to the left on the ET/D (Electronic Technician/Dealer magazine page.

It's shown as R353, Focus Divider on page 152 of the Tekfax (or page 153, as indexed by Adobe Acrobat Reader). Two resistors shown, 200 Megohm and a 40 Megohm in series, tapped at the 40 Megohm.

Same page, in the parts list, R353 is listed as a 63-9897.

Just about all Zeniths back then had the 240Meg focus divider, tapped at 40Meg. Even when incorporated in a tripler (ECG523, ECG529, ECG530) - the focus resistor values stayed the same 200 + 40 Megs, tapped at the junction. The same ECG guide I mentioned earlier has the schematics of the triplers and a description of the HI-DIV focus dividers too. HI-DIV 1 and HI-DIV 3 are identical electrically, but mechanically different for the various chassis mounting consideration......in a pinch, either will do.

If you are looking for a Zenith voltage divider, look also at the Sylvania ECG replacement types - the Hi-Div series. An ECG Hi-DIV-3 replaces the 63-9896, 63-9897,63-9898, and the 63-9898-02. Various Mounting positions are possible with the ECG replacements too - unlike the Zenith OEMs.

The Internet archive has the ECG replacement guide from 1989, if you wish to look at the HI-DIV-3 data.

https://archive.org/details/EcgSemiconductorsMasterReplacementGuide1989/page/n469/mode/1up
Brian
The thing we were trying to do is stay OEM if posable. Reason for that is
in the 80's we had a few with jail bars & a few have shown up here also.
The common thread was new caps, tripler, divider were replaced.
The 800-616 kit did not sub some dividers IIRC the 14 & 16 inch
chassis. Also the kit had the barrier & a plug for the focus. It did
sub any hybrid chassis that had a divider. With some Zenith parts
like CRT sockets, A minor difference got a new part ## but no subs.
Almost all delta sockets were the same for abt 10 yrs. The difference
was plugs & lead length, one could sub them all.

73 Zeno:smoke:

Update: My HOTs and Zenith focus dividers (63-9898-02) came in. I pulled out the old focus divider and it is.. FUBAR. It also looks like it was a 63-9895.

I have a universal Zenith HV Tripler Kit 800-791 coming in the post from Canada sometime next week hopefully.

Would it be unwise to put in the new focus divider and HOT and see if the tripler is okay?

Update 2: I replaced the focus divider with the 63-9898-02 and fitted an RCA SK3115 HOT.

There is life! Sort of. It clearly needs a purity adjustment or a degaussing.

The darker picture is with Chromatic engaged. Brightness and contrast controls are non-operable with Chromatic on. I'm not sure if this is the way it is supposed to work or not. Overall brightness seems a bit low and I am wondering if the HV tripler is slowly dying.

However, the best signal I can get through my RF modulator is.. non syncable. I can make it out a bit and the audio comes through but the picture is skewed and repeating.

There is also a light snap every 10 or so seconds coming from the HV area. Not sure what component is the cause.

The last picture was the closest I could get to a picture and this is only possible with the color turned to minimum.

Good progress! I wouldn't be too concerned with the purity on the picture with the TV on its side. Wait until you are right side up. What signal source are you using? Its doesn't look like you are on channel? If this is an RF modulated source, usually you have a choice to output on Ch 3, or 4, make sure the tuner is the same, and fine tune for to the signal. Make sure you are connected to the VHF input, don't ask how I know. Leave the Chromatic button off for now, and adjust the individual controls for the levels you want. Sorry if this is too basic?

You can obviously see why someone mummified the old focus divider.

From my experience, Triplers seem to work or they don't, except the ones that arc in the mean time.

Good progress! I wouldn't be too concerned with the purity on the picture with the TV on its side. Wait until you are right side up. What signal source are you using? Its doesn't look like you are on channel? If this is an RF modulated source, usually you have a choice to output on Ch 3, or 4, make sure the tuner is the same, and fine tune for to the signal. Make sure you are connected to the VHF input, don't ask how I know. Leave the Chromatic button off for now, and adjust the individual controls for the levels you want. Sorry if this is too basic?

You can obviously see why someone mummified the old focus divider.

From my experience, Triplers seem to work or they don't, except the ones that arc in the mean time.

Thank you! I had the fire extinguisher ready for the first power on.

I guess the RF modulator I was using wasn't strong enough. I pulled out my Agile Modulator and am able to get a usable signal at least. Color off and its not too bad, but color on even a little bit and its rough. All images are channel 4. With the agile modulator, I was able to broadcast on UHF; picture is a little bit cleaner, but more or less the same.

I was able to sort out the fine tuning of the channels and the last image is the best I was able to get. Still not great. This is also with the focus adjustment maxed out. My kit came with a 4.7 megaohm resistor if the focus can't be adjust enough, but that was for a different set. Not sure if it is applicable here.

Very good! Now you have a good sense of where you are at! Turn the color off and work toward the best B/W picture you can achieve. Nothing is going to look right with the set on its side. I would concentrate on solving the snapping every 10 seconds. It wouldn't hurt to clean in the inside of the set. I usually use a vacuum with a small paint brush and work gently through the chassis. Others will use a gentle amount of compressed air. Looks like you are inside, so that might not be your first choice. Take the tripler screws up and clean underneath and look for signs of arcing. Make sure the area around the Anode on the CRT bell is clean. DISCHARGE first, you have HV now, it will hold a charge. There are several spark gaps that may have carbon tracked or on the way, make sure CRT socket is clean and look for discoloration. Sometimes you can see the arc/snap with the room totally dark and listen carefully.

Do you have access to a HV probe to measure the HV?

Hopefully Zeno or others will chime in. I believe the added resister in the Divider Kit was to center the range of the focus control.

Good work ! Comments:.
63-9895 subs to 63-9896 also Only $6 back then !
Use the 4.7meg to center F & check the HV.
Check CRT socket. Look & smell. Most get damaged.
I dont see jail bars :banana:
Arcing. Sit behind it with lights out to spot the flash. Around the anode
they would sizzle from to much HV & leave carbon tracks. Clean up
real good with 91% isopropyl. The 2 hole anode cap also. IIRC
P## is 15-276-01 for the two holer.
Chromatic ON switches to a 2nd set of controls for bright, contrast,
color & tint. They are accessed through the hollow control shafts.
I always ran it in off pos.

On my 1971 Zenith hybrid I think I added 10-20M in series with the ground as it drifted over a couple of years in the early part of using it as a daily driver over a decade ago. Interestingly it stopped drifting and has been stable for years now.
If the focus divider is off the HV and has a path to ground then it will automatically discharge the HV after a few seconds...A splendid feature of that circuit.

Thank you all for your generous help! Certainly would not have gotten to this point without it.

I will make a list of items to work on a knock them off the list when I can. I think cleaning the contacts on the duramodules will also go a long way.

There is definitely some carbon tracks on the socket (I believe visible in one of my early photos of the set) so that will get the cleaning treatment and possibly a replacement if its too bad.

I found the source of the snap. Its my fault. There voltage divider kit I used had too short of cable for the focus and ground wires. I spliced it with the wires from the old divider (solder) then filled around the solder with silicon and heatshrinked it. Apparently it wasn't thick enough and its arcing from the solder joint to ground (about a millimeter arc). Is there a more suitable way to lengthen high voltage cables besides finding the right kit?

Is there a more suitable way to lengthen high voltage cables besides finding the right kit?

IMO Probably not without a suitable insulated inline connector. Zenith in later designs evolved away from the exposed focus tie point on the flyback frame. The "CAUTION HIGH VOLTAGE AREA" label to the left of the tie point is quite appropriate.

It looks like the ECG or NTE HiDIV4 which is also a SK3871/DIV-4 is a nice part to have for this application. Multiple mounting options and long leads for every need.

Not to confuse things but you still have the option of going to a Tripler with an internal divider. I will try to post a scan from Sams 1375 tomorrow that indicates the Late Production 25DC56 and 25DC58Z went to a 212-141 Tripler. Which was "Preferred to CR224 and R361"

If you plan on watching this set, which is a really nice TV, the best advice would be to use the right part in the end, whichever direction you go with the focus divider. What you have now was useful for troubleshooting. Interesting, the Avanti series are still sought after. One of the few sets you could sell and get your money back out of it...... you would not want to quit your day job...

In your previous pictures the greenish tint on the back of the CRT socket is an ominous sign.

Don't forget the Degaussing thermistor from your earlier post. I can't tell from the picture if it is cracked or the lead broke off or not.

These are the changes documented in Sams for the 25DC56 Late Production. I haven't had any luck finding a copy of the Zenith manual. Interesting they added the spark gap as well.

Is there a more suitable way to lengthen high voltage cables besides finding the right kit?

Easy Peasy. Double wall heat shrink and corona dope - Corona Dope is an anti-corona coating with a high voltage/mil strength that is used to prevent arcing. Double wall heat shrink (available from NTE) is what we used - with 100% success.

Corona Dope - GC 10-5002 is the good stuff. Dod specified it for connections above 40KV on airborne radars, followed by Humidseal. We used it with the AWG-9 (Tomcat) radar. Let it dry well before shrinking the heat shrink to prevent cracking (from uncured layers within...)

Double-wall heatshrink - NTE Part No: 47-23248-R (red) - 3;1 shrink ration, 3/16" and 1/4" cover 90% of electronics needs for HV insulation.

Our bench test jig HV connection was jury-rigged - we used a plastic squeeze bottle like they use for ketchup in restaurants. It kept the connection from arcing - and only one hole needed drilling.

IMO Probably not without a suitable insulated inline connector. Zenith in later designs evolved away from the exposed focus tie point on the flyback frame. The "CAUTION HIGH VOLTAGE AREA" label to the left of the tie point is quite appropriate.

It looks like the ECG or NTE HiDIV4 which is also a SK3871/DIV-4 is a nice part to have for this application. Multiple mounting options and long leads for every need.

Not to confuse things but you still have the option of going to a Tripler with an internal divider. I will try to post a scan from Sams 1375 tomorrow that indicates the Late Production 25DC56 and 25DC58Z went to a 212-141 Tripler. Which was "Preferred to CR224 and R361"

If you plan on watching this set, which is a really nice TV, the best advice would be to use the right part in the end, whichever direction you go with the focus divider. What you have now was useful for troubleshooting. Interesting, the Avanti series are still sought after. One of the few sets you could sell and get your money back out of it...... you would not want to quit your day job...

In your previous pictures the greenish tint on the back of the CRT socket is an ominous sign.

Don't forget the Degaussing thermistor from your earlier post. I can't tell from the picture if it is cracked or the lead broke off or not.

Thank you for the info on the substitution! My apologies in the delay, I had to step away from the set for a couple weeks. This TV will be a daily driver once I get it all sorted.

I've got a saved search should a 212-141 show its face, but so far no luck. Unless the focus divider I am using just doesn't work out, it will probably stay as I also have a NOS 212-130 universal tripler ready for use.

I agree on the socket, that will be taken apart and cleaned. Hopefully it doesn't require a replacement. I have also ordered a replacement thermistor per the service manual (surprisingly still available). The old one is cracked in half. Apparently it is common for these to just crumble away over the years.

Easy Peasy. Double wall heat shrink and corona dope - Corona Dope is an anti-corona coating with a high voltage/mil strength that is used to prevent arcing. Double wall heat shrink (available from NTE) is what we used - with 100% success.

Corona Dope - GC 10-5002 is the good stuff. Dod specified it for connections above 40KV on airborne radars, followed by Humidseal. We used it with the AWG-9 (Tomcat) radar. Let it dry well before shrinking the heat shrink to prevent cracking (from uncured layers within...)

Double-wall heatshrink - NTE Part No: 47-23248-R (red) - 3;1 shrink ration, 3/16" and 1/4" cover 90% of electronics needs for HV insulation.

Our bench test jig HV connection was jury-rigged - we used a plastic squeeze bottle like they use for ketchup in restaurants. It kept the connection from arcing - and only one hole needed drilling.

The parts you listed have just arrived in the mail. I've never seen so many warnings of death and harm on a such a small bottle... :smoke:

I'll be waiting for a warm day to do this outside. Thank you for the recommendations!

Finally had a nice warm day. I was able to correctly extend the divider wires with the red-x corona and double wall shrink tubing. So far no arching!

I opened up the picture tube socket and it was pretty clean. I removed any light dirt/traces and buttoned it back up. The degaussing circuit thermistor was replaced with an equivalent IAW the service manual. I also replaced the divider resistor with the one including in the kit (I forget the ohms off the top of my head). It helped with the focus, but what you see in the pictures is maxed out. For good luck, I cleaned all of the dura-module pins and re-seated each one.

Long story short, we have some real life now! I gave it a quick pass with the deguass wand and that sorted out most of the impurities. However, it is in dire need of a convergence alignment. I'm hoping that this will help with focus as I am still not impressed with it. The picture is currently wider than it out to be (need to find the horizontal adjustment) and there is some vertical linearity issues that the adjustment couldn't quite sort out.

Next up is to de-oxit the control pots and work on going through the service manual for calibration.

Is there anything that I should replace on the dura-modules before continuing? This TV will be a daily driver once fully up and running. Of note, I got a nasty shock when I touched the metal frame around the picture tube on the front of the TV after powering it up for the first time. It did not occur again. Not quite sure what was the cause of that.

On the 9-57 hoz board check for a 330 ohm IIRC. go to a
1 watt film.
Clean the service switch ( rear ) & normal - align sw ( top ).
Semis on modules if they plug in should be cleaned. If they go int
remove the socket. The sockets were more trouble than the parts.
Remember when doing the conv. the center is ONLY the center.
Ignore T, B, & sides. Brite & contrast should be about 1/2 turn
so as not to drive it too hard.

73
Zeno:smoke:

If the set is focusing such that you can defocus by rotating the control either direction from optimum, turn down the brightness some and adjust the focus again as well as the fine tuning...If the pot is at one extreme adding something 2M resistance to the end the end it's butting up against may help.

Hello all,

Sorry for the hiatus again. I've had time to spend a solid day working on this set. Items replaced before starting:

S-84384 coil (my slug broke inside)
212-72 rectifier (mine was cracked and falling apart)

I was able to replace all but the Chroma Duramodule with NOS modules that I happened upon.
I added another 2M ohm to the focus pot such that I can get to either side of out of focus and then center it. Personally I think its still blurry but that is either my expectations are a little high for the set.
I also noticed that the image is shifted to the right. I cannot find any horizontal position adjustments however.

Following the manual and advice I just cannot seem to get this set to align properly. My left and right sides are always out of alignment against the blue no matter what is tried. Convergence strips needed maybe? Below is the best I could get after about 4 hours. Given the age of the set, what level of compromise should I expect?

Is the vertical linearity as bad as it looks in the photo, or is it just the angle of your camera? Bad vertical linearity can affect convergence.

Is the vertical linearity as bad as it looks in the photo, or is it just the angle of your camera? Bad vertical linearity can affect convergence.

The angle of the photo skews it. Its not perfect, but its not to that degree. I am going to try adjusting the purity tomorrow and see if that helps any moving forward.

The pix is not up to how they looked. I think the CRT is a little weak.
That will make it hard to set up. Cant tell for sure from up here in NH. !

Check a few things.
Boost, 1K resistor on focus pin if CRT, be sure instant on
is working. Also for laffs check the CRT date codes & EIA ## to
see if its OEM. Check diodes on convergence panel.

73 Zeno:smoke:
LFOD !

In the earlier picture with crosshatch and circles, the height is way too big. If this is still true, it will affect convergence. Make sure the height is correct before proceeding.

The pix is not up to how they looked. I think the CRT is a little weak.
That will make it hard to set up. Cant tell for sure from up here in NH. !

Check a few things.
Boost, 1K resistor on focus pin if CRT, be sure instant on
is working. Also for laffs check the CRT date codes & EIA ## to
see if its OEM. Check diodes on convergence panel.

73 Zeno:smoke:
LFOD !

Too bad I didn't get this far on it while I was still in CT last year!
I am not sure what you mean by "Boost" but I checked the resistors out when I had the socket apart, all good there. Instant on is working.

I attempted to re-do my purity and I think that helped a bit. I re-seated all of the Semis. The 221-46 Semi on the Chroma Duramodule had two legs fall apart. Thankfully I had a NOS one from another Duramodule and that did the trick.

The CRT is OEM and an AG125VB0P22 (if I read the faded label right) with a date code of 4-13 punched out. Early on I complained of faint letterbox burn in. It never came across in the pictures, but it is certainly there. It wouldn't surprise me that this is a high mileage set. The red gun certainly seems weaker/more orange in comparison to blue and green when turning each color down.

Below are my best shots so far. I'm going to order some convergence strips for the left side. But other than that this may be where the set sits for awhile as I am bit burnt on it.

Is it feasible to source an Chromacolor tube for this unit? I have heard of people who hoard them.

I'm 95% I am dealing with a weak CRT. Hopefully I can find someone with a tester near Denver area.

Would replacing the HV tripler help at all? If that HV divider was destroyed its a possibility the tripler took some damage. I am not sure what the symptoms of too low of HV would be though.

Yup thats the original jug. Almost 50 yrs & still quite usable.
Make a list for subs. CC2 sets are real common & probably use
the same one. Just be sure its a 30 Kv tube. Hybrids will
have 25 Kv so no go. I think you have a 25VDQP22
check the Sams.
The set up looks good. Last test is turn off the lights & turn everything down low. If the pix gets sharper its CRT

Zeno

I've been checking possible replacement tubes off and on lately. I have a line on a NOS 25VAQP22, but I am not sure if it is a possible replacement.

I know the following information.

I have a 25VBQP22 in the set (looked like a D in the picture, confirmed with the Sams).
Per a 1976 Zenith interchangeability guide, the 25VAQP22 and 25VBQP22 (also equivalent to a 25VBNP22) are both replaceable by a 25VCNP22.

Per a 1982 Zenith guide, the 25VAQP22 is listed as a direct replacement for the 25VBNP22.

I am fairly confident that the 25VAQP22 will replace the 25VBQP22 based on that chain of equivalences, but I was wondering if anyone has information regarding this?

I am at the same place with my 25DC56 restoration. My set has the original Zenith 25VBQP22 CRT. I believe my set is low hour but it was plugged in it's entire life, prior to me purchasing it on FB last year. My CRT tests good on a Sencore CR70 but does not test well with the life test. The red gun is the weakest of the 3 and no matter how I set it up, it does not want to track well. The focus peaks but isn't very good. It looks much better in low light. I did not try to rejuvenate/restore because it is still watchable. I'm hoping to get my set to a better level.

I have several generations of Zenith, Video Display, and Sylvania CRT guides and came to the same conclusion you did that the 25VAQP22 was a substitute. I was able to find a VDC 25VAQP22 and plan to install it over the holiday weekend and will let you know. Is the tube you are considering NOS or rebuilt?

I haven't been able to understand how a rebuilt VDC 25VAQ compares to the original Zenith CRT? Black Matrix? How did the rebuilders, Zenith, Sylvania, RCA, VDC, compare with each other?

Zeniths solid states with DC, EC FC & maybe CC chassii are
instant on. Be sure its working, when turned on cold it should come
right up in a few seconds.
All flat chassii & early CC2 uprights MUST have new 22-5001 HV
safety caps IF they are white. Orange ones are OK.
Late EC & FC chassii uses the 4 lead cap. Be sure it is orange.
Also be sure you use the right one ! There are at least 3 others for different
Chassii such as 13", EFL CRT's , System 3 etc. Most uprights
used the 800-860 kit BUT be sure !

enuf fer now
73 Zeno:smoke:
LFOD !

I am at the same place with my 25DC56 restoration. My set has the original Zenith 25VBQP22 CRT. I believe my set is low hour but it was plugged in it's entire life, prior to me purchasing it on FB last year. My CRT tests good on a Sencore CR70 but does not test well with the life test. The red gun is the weakest of the 3 and no matter how I set it up, it does not want to track well. The focus peaks but isn't very good. It looks much better in low light. I did not try to rejuvenate/restore because it is still watchable. I'm hoping to get my set to a better level.

I have several generations of Zenith, Video Display, and Sylvania CRT guides and came to the same conclusion you did that the 25VAQP22 was a substitute. I was able to find a VDC 25VAQP22 and plan to install it over the holiday weekend and will let you know. Is the tube you are considering NOS or rebuilt?

I haven't been able to understand how a rebuilt VDC 25VAQ compares to the original Zenith CRT? Black Matrix? How did the rebuilders, Zenith, Sylvania, RCA, VDC, compare with each other?

I look forward to hearing back from your efforts! I was able to get a NOS tube, but am currently working the shipping logistics part of it.

I currently have the same issues as well, but have done all of the replacements mentioned by Zeno. (Set comes on quickly). Thanks again Zeno and all who chimed in for helping getting my set to at least the "usable" level it is at.

Hello all, been awhile!

I've got a good Sylvania 25VAQP22 from ETF sitting in the garage ready for an install. I will begin chassis and picture tube removal in the near future. I will be taking my time and attempting to restore the cabinet at this time as well.

I've located the disassembly instructions in the service manual and it looks more or less straightforward. Does anyone have any tips/tricks/gotchas when doing this kind of work? And with this 25DC56 chassis, are there any items I should touch while the chassis is out of the console? I plan on installing a new voltage tripler given how destroyed the divider was.

Hello all, been awhile!

I've got a good Sylvania 25VAQP22 from ETF sitting in the garage ready for an install. I will begin chassis and picture tube removal in the near future. I will be taking my time and attempting to restore the cabinet at this time as well.

I've located the disassembly instructions in the service manual and it looks more or less straightforward. Does anyone have any tips/tricks/gotchas when doing this kind of work? And with this 25DC56 chassis, are there any items I should touch while the chassis is out of the console? I plan on installing a new voltage tripler given how destroyed the divider was.

Most sets the CRT comes out as an assy with DGS shield, conv, yoke etc.
Lift out by sides NOT neck. To have grab room put a box a little smaller under the face of CRT. The cabinet will drop away. Move to a table & transfer parts.
Install.
A helper is good, he can lower the cabinet slowly & hold it up to
get the MTG screws started.
Have fun :thmbsp:

Zeno:smoke:

One other thing. Xcelite used to make an extra long 1/4 inch
magnetic nut driver. I would guess its 25" - 30" long. If you can find one its a must for some sets. Also comes in phillips & #10.
I will see if I can find mine & post the model ## for the group.

Zeno:smoke:

Does anyone have any tips/tricks/gotchas when doing this kind of work?

Just one.

Take lots & lots of pics of everything before, and during taking it apart. :thmbsp:

Model for driver is Excelite LL-8-M- 1/4
Overall 21" long. Its needed for 19" Zenith hybrids. CRT screws & tuner screws very hard without it.
I have two of them. Cant make up my mind weather to leave each son
one or get buried with one & let them fight over the other !
They are on E-bay sometimes.

Zeno:smoke:
LFOD !

Just one.

Take lots & lots of pics of everything before, and during taking it apart. :thmbsp:

Most certainly!!

Model for driver is Excelite LL-8-M- 1/4
Overall 21" long. Its needed for 19" Zenith hybrids. CRT screws & tuner screws very hard without it.
I have two of them. Cant make up my mind weather to leave each son
one or get buried with one & let them fight over the other !
They are on E-bay sometimes.

Zeno:smoke:
LFOD !

Thank you for the tip about the box, sure that will come in handy! I was able to snag a 21" LL-8-M 1/4 on today, its going to save my bacon.

While I was looking around, I figured I should probably get some proper tools. I picked up an B&K HV-40 probe as well.

I am currently looking at NTSC Pattern Generators and I was wondering if you had any recommendations? I am between the B&K 1246 and the Leader LCG-396. I am leaning towards the Leader for the color bar ability, but thought I would ask around before committing.

Look at the Sencore VA48 & VA62 also. We ran them with good
luck. They will do almost everything. Be sure it has BOTH manuals !

Zeno:smoke:

Picked up a VA62 in good working order. Hopefully it survives the post. No manuals, but thankfully all manuals and schematics can be found freely online. :banana:

Hello all,

Here for the yearly check-in! Glad to see that Videokarma is back up and running. Was a bit worried all of this thread was lost to the wind. I backed it up manually just in case.

Anyhow, finally had some downtime to get into this set again. Turns out my replacement tube is actually a Motorola MV 25VAQP22. Hopefully it works well, at least it is not a rebuild to my knowledge.

Looks like the Tripler was replaced with a "SCI 212-139" at some point. I still plan on replacing it with my NOS Zenith universal Tripler. I did notice that it has a "focus" lead, but the current setup has the focus running through the divider instead. Unfortunately it did not come with the usual documentation in the box so I am unsure the best way to handle that.

Currently repairing the base with some epoxy and giving it a repaint while I work on the electronics. Fingers crossed the swap goes well.

While the label says Motorola, the EIA Code 312 is made by Sylvania. Do you see a date code anywhere?

The yoke bracket is secured with double-sided foam tape, probably no longer pliable. I use a plastic spackling knife to gently separate the bracket from the CRT envelope. You will need some double-sided foam tape to resecure. The plastic yoke cases are also no doubt brittle, baking in place for over 40 years, remove gently.

It would be very interesting to know from the engineers who designed these sets, how long they thought they would last???

Your exisiting Tripler looks original to me. If its producing 25KV and its not arcing, its doing what it needs to and could outlast everything else. You could pull the screws, look for signs of arcing, and clean underneath. Your replacement divider looks good.

While you have the chassis out, consider replacing:

The boost filter, if you are using SAMS its C270 10uf 300v, this capacitor takes a beating, and can impact the picture quality.

4.7Meg 2w resister from the focus control to ground. I often find these drift, so will the focus, the original is a carbon comp resister.

Happy New Year!

While the label says Motorola, the EIA Code 312 is made by Sylvania. Do you see a date code anywhere?

The yoke bracket is secured with double-sided foam tape, probably no longer pliable. I use a plastic spackling knife to gently separate the bracket from the CRT envelope. You will need some double-sided foam tape to re-secure. The plastic yoke cases are also no doubt brittle, baking in place for over 40 years, remove gently.

It would be very interesting to know from the engineers who designed these sets, how long they thought they would last???

Your existing Tripler looks original to me. If its producing 25KV and its not arcing, its doing what it needs to and could outlast everything else. You could pull the screws, look for signs of arcing, and clean underneath. Your replacement divider looks good.

While you have the chassis out, consider replacing:

The boost filter, if you are using SAMS its C270 10uf 300v, this capacitor takes a beating, and can impact the picture quality.

4.7Meg 2w resister from the focus control to ground. I often find these drift, so will the focus, the original is a carbon comp resister.

Happy New Year!

Unfortunately no date code, not that I can find anyway. Its possible that Sylvania was the OEM for Motorola's CRTs.

The bracket on the replacement tube fell right off, but it looks like the Zenith one is going to be a bit more a job. I have some good double sided foam mounting tape that will do. Fingers crossed everything comes off in one piece.. this is a very high hour set.

As for the tripler, the I replaced the divider after the old one was cracked and covered in HV putty. After seeing that, I am suspicious of the tripler, even if it looks fine. I've got it all apart so might as well while its out and keep the SCI as a spare.

I'll take a look at those components and see if I can source some replacements.

Since I had to epoxy the base and repaint it, I figured why not make the set unique. I give you the Golden Sunshine Avanti.

It's definitely unique. If I was going to go with a custom period color I think I pick Avocado green though.

I looked for a good Avocado green that was gloss and worked for both plastic and wood, but no dice. We had a few favorable days of warm temperature before it goes back to cold so ran with the next best color I could find.

Got around to putting the chassis back in and firing it up!

Got snow and then hooked up the function generator and got worried with the crosshatch image. Triple checked all of my connections were correct and finally found the culprit. Turns out I knocked one of my socketed transistors on the Horizontal module out and it was just laying on the chassis. Thankfully it didn't short any connections. Hooked that back in and got horizontal lock.

Lots of adjustments needed, but it works! Tube appears strong. I ended up removing the extra 4.7 MOhm resistor in series from when I installed the new divider to allow the focus to center.

Work done on the chassis: NOS universal tripler, replaced the 10 uF 300V capacitor as previously recommended, cleaned (deoxit + wire brush) all module connections, DeOxit + Fader Lube on all pots, overall clean to get rid of grime.

On to what will no doubt be a lengthy alignment period. Glad it didn't blow up.

Your new CRT does look strong! A great amount of what you are seeing will clean-up with purity and static convergence. Excellent progress!!

Hello all,

Exciting update! Thanks to help from BeamT, the set has come back from the dead. I was working on the convergence and just couldn't get it right. Turns out you need to have a lateral blue magnet, of which my set was missing. BeamT sent one in the mail and it worked great!

This is the first time the set has really been up in running in years. I am currently chasing down a brightness issue with the set.

The problem: Intermittent pulses in brightness. Sometimes whole screen, sometimes brief sections of the screen get brighter. Overall brightness seems to be down. The Plex picture is at max brightness and it can barely pull apart grey from black. Along with this, there has also been some screen jerking in the horizontal direction, usually bottom portion of the screen. Some fluctuations will also occur and can be audible through the speaker. I've recorded a video of the issue, but will have to link it later.

Work Done: I replaced the Horizontal module (9-57) back to the original one in the set (had replaced with NOS). Initially, this brought the brightness back up and it held until power down of the set. Since power cycling, cannot get this to reoccur. I measured the 24V (24V read) and 125V B+ (123V-125V tuned to blank channel, 135-137V tuned to active channel). High Voltage reads dead on 26 kV. No arching or abnormal noises. Percussive maintenance did not reveal and lose or intermittent connections. All pots have been thoroughly cleaned with DeOxit and Faderlube.

Appreciate any ideas on this! Its so close to being finished (until something else thats 50 years old fails).