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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Aug Sun 25, 2019 10:37 pm 
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Don Cavey wrote:
... What makes them bad? Physical damage.


Meaning damaged by breaking them...

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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Aug Mon 26, 2019 3:20 am 
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The bulge is just how they are made. They were just a little sloppy with the coating covering the working part of the cap. That is one of 3 styles of ceramic caps.

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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Aug Mon 26, 2019 6:40 pm 
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Those maroon ceramics should be fine unless they test electrically defective. They were made with that bulge. If they bulged like that after the ceramic was baked at the factory the ceramic would have cracked apart in an obvious way.

That paper body cap the schematic shows as plastic bodied paper that you claim was replaced by someone...did the solder workmanship match the rest of the set, or was it different? If it matches factory workmanship quality then it probably was a production change... Many factories would make hundreds of thousands of a given TV chassis and part values might change as much as a dozen times before manufacturing ends...most changes are improvements, some were to compensate for parts substitutions. Parts substitutions could happen several times a week depending on supply chain for things like capacitors resistors, etc...if Sprague couldn't give admiral 50K .047uF 400V black beauties this week they would call up sangamo and ask for 50k .047uF 400V little chiefs... nobody cares what brand it was as long as the critical numbers matched and it mechanically fit.

Sam's tried to record production changes but didn't capture a good portion of them.... Sam's also is somewhat prone to typos so when recapping a set always scrutinize the workmanship of what is there for originality...if looks professionally done but is different from the schematic then it is probably there for a good reason, but if it looks like some druno schmoe just soldered some random part in using his feet to hold the iron then you probably want to change back to the schematic configuration.

I don't think I've ever seen someone take video of doing a solder job on a long term replacement of a lytic can (seen plenty of troubleshooting vids where someone connects a cap with clip leads). You can find various pictures of finished recapping jobs give you layout inspiration...lots of them out there. Really what you want to do is REALLY read the schematic diagram of the circuit and understand where every wire on the can goes to and what it looks like on the schematic ( the spaghetti diagram with heiroglyphics depecting components not the photos)... once you can trace schematic to physical object and back your good. There are probably more than 100 valid physical ways to layout the new caps in the chassis that will all work perfectly... what counts is that the electrical connection map between the all items on each end of every wire you touch be the same.


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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Aug Sat 31, 2019 10:47 am 
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Updates...

Capacitors - I have been replacing the ordinary paper/plastic capacitors and tonight finished replacement of all of this sort on the sync circuit sub-chassis and had previously completed the video IF sub chassis. It was mostly straight forward and I didn't encounter any more issues with the PCB trace solder peeling off. As I worked at it I tested the removed capacitors in the cheap modern capacitor test that only tests for capacitance (not leakage nor voltage load). Some were quite at variance while many were still around the tolerance threshold. But again I suspect we'd see these have leakage or other issues in a proper tester so it was good to replace them all. I also did the basic test on the new ones before replacing them to ensure they were accurate. I have the sound board to do next, even though the sound currently sounds perfect. There are a few high voltage capacitors that are mounted behind the chassis that I am still awaiting replacements for (e.g., .001uf 1600V and .047uf 1000V). Those ones should be very easy to replace once delivered.

Electrolytics - The remaining electrolytic caps are the two canned styles. One concern is that I was unable to find 60uf for less than around $20 each and I need two of them. I did purchase and receive 68uF 400V for cheap—will that difference (12%) be suitable or is it too extreme? I understand I could alternatively chain several together but I'm not sure I have any good combo for that either. I have a lot of 47 and 4.7 electrolytics but would need to tie three together to equal 56.4. I also have many other sizes that'd make things easier to combine with the 47uF but the others are only 25V. But if the 68s would be acceptable I already have those on hand. I have been reading the articles on different approaches to this and will likely try this over the weekend.

Ion Trap - This part completely escaped my memory until I watched bandersen's video on a similar restore. This set did include a cardboard ion trap that I had stored away when originally messing with it. I honestly didn't realize at the time that this was anything other than a brace or such and still am quite confused on how it should be situated or if it is necessary since the picture tube manual states no ion trap is required and my replacement aluminized screen seems to suggest it is optional as well. Perhaps the one included was carry-over from the very original picture tube. The ion trap includes two adjustment rings that you can manipulate individually and it does seem to affect the screen to some extent but I'm not sure of its significant. I also see "Ion Trap" and "Centering Magnet" used distinctly and am still confused of their purposes or necessity.

Video Quality Although I haven't tried any DVD since recapping, the replacement of the caps I've already finished seemed to greatly improve many aspects of the display even on the clearly poor CRT. This appears to had resolved a lot of the distortion and skewing that was initially going on. However, it seems to be overly sensitive to vertical scrolling and will continue to slowly scroll/wrap vertically no matter how meticulous I am with adjusting the controls (including vertical height, vertical linearity, and vertical hold). I'm still not real familiar with the relationship between these items and there appears to be many possible combinations I can set between them to still get the picture to appear properly synced (minus the scrolling issue). Speaking of controls I wonder if they need to be serviced in any way themselves as they may seem a bit over-sensitive/touchy.

Bottom Video Cut-Off Still Occurring Unfortunately I still get the issue where the bottom of the display is cut off straight across. This cut off area does rotate as the yoke does and is always at the original bottom of the yoke (so if yoke is rotated 180' the black bar will appear on top instead of bottom). It almost feels like it is a centering/alignment issue but I haven't been able to figure it out. I can try to record video of this to better demonstrate. I wonder if replacing the CRT itself may resolve it or if the remaining bad caps/electrolytics might.

Center Dot Stays For Long Time on Power-Off - After powering it off, the beam hits the center of the TV and remains for around 3 minutes before it fades completely. I noticed this when I had first gotten it as well.

Here is a 9 second video showing the current video functionality; if I can resolve the scrolling and cut off issue I think I will be in great shape to wrap-up this restoration! https://www.youtube.com/watch?v=nqvn9TgqY1A


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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Aug Sat 31, 2019 3:27 pm 
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The 68 uf should do fine. usually the factory tolerance on electrolytics is very wide, something like +50%,-20%.
I hope when you say cheap that it isn't as old as the TV.

I do think you are talking about the centering magnet assembly, the triangular cardboard like thing. Some TVs use a DC current through the yoke windings for centering and I think some used movement of the yoke. Ion traps, also called beam benders, have a kind of horseshoe shape that wraps (clamps) around the CRT neck.

It is possible that some of the controls are dirty.

I doubt that the cut off bottom of the picture is due to the CRT. It could be the vertical output transformer, the yoke, the vertical output tube or some other part.

The lingering dot after turning the TV off is a characteristic of TV of a certain vintage. Many people think it is sign of the real thing, so to speak. It is there because the voltages on the CRT are still there for a time after the sweep circuits stop. There is a circuit, that will turn off the gun immediately, that you could add if it bothers you. Later sets had something like it.

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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Aug Sat 31, 2019 5:41 pm 
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the lack of vertical height is not the crt. recap the vertical section. if that doesnt fix it you can then check resistors in the vertical circuit. this is the most likely. you can do a resistance check on the vertical winding on the yoke. if it is close to what the service notes call for it is most likely not your problem. the same for the vertical output transformer. the vertical roll is also part of the vertical circuit and not caused by the crt.

an ion trap is only used on early crt with a bent gun. they suffered from ion burn so the gun was cut at an angle. this would cause the electrons and ions to shoot out to the neck of the picture tube so they wouldnt hit the phosphor mask at the front of the screen. an ion trap would bend the electron beam so the electrons would hit the phosphor mask on the crt but the ions being heavier would not.

a centering ring is used to center the picture on the crt. it is not the same as an ion trap.

could you show a pic of the part you thought was an ion trap because to the best of my knowledge an aluminized crt does not use one. also if memory serves if your crt needed a ion trap and the ion trap was not present or was misadjusted you would get no light on the crt at all.

electrolytics had a tolerance of +80 -20 so the 68 mfd ones should be fine as long as the voltage rating on the origional electrolytics is not greater than 400 volts. never go lower on the voltage ratomg but higher should be fine.

Center Dot Stays For Long Time on Power-Off do not worry about this it is normal.

maybe it is the youtube video but the pic looks to me like it has poor contrast and is blurry. this could be caused by weak video tubes components in the video circuit or a weak crt.


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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Aug Sat 31, 2019 9:17 pm 
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Here is what that cardboard piece looks like. You can see this in place on the original tube in this video which is of the exact same set I have. The metal rings can be rotated and the springs would connect to the back of the chassis when everything is in place to hold it steady.

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Quote:
the pic looks to me like it has poor contrast and is blurry. this could be caused by weak video tubes components in the video circuit or a weak crt.


It definitely is. I can adjust the contrast but never to the point of it looking real good. And yes everything is heavily blurred which was what I initially described as "ghosting" in an early update. Here is what text looks like up close. You can see how everything has heavy shadows.

Attachment:
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I assume that these artifact issues are from the very poor condition CRT itself (gases etc), which originally had a brightener attached. My B&K 465 was essentially unable to get any reading at all from the CRT when I tested it, marking it at the lowest on the "Bad" scale (and when I did the 6V battery test prior to that the CRT was getting terrible results as well). The new CRT I have tests great with the CRT tester.

I may honestly swap out the old CRT for the new this weekend and see what a difference that makes visually. It apparently won't resolve the vertical issue/cut-off which I still have to narrow down but will be good to see if the quality and such is much better.

Quote:
the lack of vertical height is not the crt. recap the vertical section. if that doesnt fix it you can then check resistors in the vertical circuit.


Just to be clear the "vertical section" and "vertical circuit" mentioned above are two separate regions--part of the "Video IF Sub-Chassis" or the "Sync Circuit Sub-Chassis" boards? At this point I believe I have replaced all of the paper-like capacitors on both of these boards. The only ones I haven't were the micas and related ceramic ones. I do have the electrolytic cans (C1. C2) and a couple larger non-board mounted capacitors on the back (C44, C67, C77) to replace yet. To test resistors do I have to generally remove one lead from the board first?

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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Aug Sat 31, 2019 10:56 pm 
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MattPilz wrote:
Here is what that cardboard piece looks like. You can see this in place on the original tube in this video which is of the exact same set I have. The metal rings can be rotated and the springs would connect to the back of the chassis when everything is in place to hold it steady.

Quote:
the pic looks to me like it has poor contrast and is blurry. this could be caused by weak video tubes components in the video circuit or a weak crt.


It definitely is. I can adjust the contrast but never to the point of it looking real good. And yes everything is heavily blurred which was what I initially described as "ghosting" in an early update. Here is what text looks like up close. You can see how everything has heavy shadows.

I assume that these artifact issues are from the very poor condition CRT itself (gases etc), which originally had a brightener attached. My B&K 465 was essentially unable to get any reading at all from the CRT when I tested it, marking it at the lowest on the "Bad" scale (and when I did the 6V battery test prior to that the CRT was getting terrible results as well). The new CRT I have tests great with the CRT tester.

I may honestly swap out the old CRT for the new this weekend and see what a difference that makes visually. It apparently won't resolve the vertical issue/cut-off which I still have to narrow down but will be good to see if the quality and such is much better.

Quote:
the lack of vertical height is not the crt. recap the vertical section. if that doesnt fix it you can then check resistors in the vertical circuit.


Just to be clear the "vertical section" and "vertical circuit" mentioned above are two separate regions--part of the "Video IF Sub-Chassis" or the "Sync Circuit Sub-Chassis" boards? At this point I believe I have replaced all of the paper-like capacitors on both of these boards. The only ones I haven't were the micas and related ceramic ones. I do have the electrolytic cans (C1. C2) and a couple larger non-board mounted capacitors on the back (C44, C67, C77) to replace yet. To test resistors do I have to generally remove one lead from the board first?

Yes, that is the centering ring assembly. Many TVs have these rings attached to the back of the yoke.
I think that blurring is most likely because of the CRT. I don't think I've seen anything like it.
"Vertical section" and "vertical circuit" can refer to the same thing, most of it would be on the sync board.
After you finish the re-cap is the better time to do trouble shooting. You are going to fix problems in the process of re-caping, then you can see what problems remain. As was said, leave the ceramic and mica alone until they are suspected to be the cause of a problem. Some resistors can be accurately tested without
un-soldering, some cannot, it depends on the circuit connection. Since you are probably fairly new at reading a schematic to tell, the simplest aproach is to un-solder one side of the resistors.

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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Sep Sun 01, 2019 12:48 am 
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i wish i had an online pic of a tube tv block diagram to show you but i dont. a tv is made up of several sections. rf if video audio sync vertical horizontal and high voltage.

the vertical section is comprized of the vertical multivirbrator also called vertical osc vertical amp in older sets vertical output tube vertical output transformer vertical winding on the yoke and associated components. if memory serves the vertical osc vertical amp were seperate tubes in old sets.

by vertical circuit i ment the individual components in the vertical section.

the sync section would be the sync tubes and associated components. i do not know if the vertical section has its own board or is on the same board as the sync section without looking at the service notes. it could be either.

a quick check of the resistors in the vertical section is if the schematic has resistance chart for each of the tube socket pins of the vertical tubes you can make the measurement from the different socket pins to ground. any pin that shows a resistance that is off by more than 20 percent would indicate that individual components connected to that pin need to be checked individually. you can also make voltage measurements at the tube socket pins and any pin that the voltage is off by more than 20 percent would indicate the necessity of checking individual components connected to that pin.

the answer to whether you need to lift one end of a resister to measure it is it depends. if a component is in paralel with the resistor then yes if no component is in paralel with the resister then no. a time saving thing is to measure the resister in circuit and if it reads in tolerance leave it alone. if it is out of tolerance lift one leg and measure it again. if it now reads in tolerance reconnect it to the circuit. if it still reads out of tolerance replace it.

the cardboard part in your picture is definitely not an ion trap. that is the centering rings for your set.

do not replace the crt with the new one untill all work is finished. all you need is to nock the chassis over and hit the new crt or drop a tool on it and the new crt is toast. i know it is tempting to see what it will look like with the new crt but dont do it till the repair work is done. the old crt is pretty much dead so you could try the rejuvinate function on your crt tester on the old crt. you dont have much to loose. this could improve it for awhile or kill it outright. does the brightener help anything at all. if it does you could try that on the old crt. never put a brightener on a strong crt.


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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Sep Sun 01, 2019 8:37 am 
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The centering magnets can cause that blurring if misadjusted. Try it without them to see.

If the gun inside the CRT neck is NOT bent (it will be obvious) then an ion trap should NOT be used. It can also cause that blurring.

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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Sep Sun 01, 2019 12:34 pm 
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Well, I had an unfortunate setback after attempting the C2 electrolytic can repair... For starters, the existing connections to it differ almost entirely from the schematic (I stuck with this configuration for the replacement, assuming it was done for some valid reasons previously). This is C2:

  • (C2-A) ▲ 5µ/200 | (C2-B) ■ 60µ/200 | (C2-C) 20µ/50

In the schematic, the connections indicate (see photos):

  • C2-A ▲ branches to R38 (8.2K) and V6 (Video Output Tube).
  • C2-B branches to C3(-) (40µ elec), C58 (.0047µ cap) and V11 (Audio Output Tube)
  • C2-C ■ branches to R5 (3K - Vertical Linearity Control), C4(-) (10µ elec) and V13 (Vert Multi Vert Output Tube).

However, the actual wiring in the chassis itself was very different... It was:

  • C2-A ▲ - One connected wire; Branches to R38 (8.2K) (this one seems to match schematic)
  • C2-B - No wires connected at all
  • C2-C ■ - Three connected wires; 1 to noise gate control, 1 to audio sync board cap, 1 to C3(-)

I hooked up new electrolytics in this same style (the 3 wires reconnected to positive of ■ replacement, the 1 wire reconnected to positive of ▲ replacement, nothing connected to positive of C2-B ... all negatives chained together ultimately to chassis).

Turned it on and image was badly wobbly/distorted and scrolling. When attempting to adjust the vertical linearity (I believe I was turning it counter-clockwise) suddenly "POP" saw a spark and screen turned to just a washed out gray... I believe I traced it to the Damper tube which now appears fried and filaments busted.

So clearly something got screwed up in the translation to the new electrolytics. I did not have a terminal strip to more cleanly connect each electrolytic so the cables/leads were merely soldered ad-hoc together. Originally I had tried cutting off the old metal can to use its base to mount the new as I saw in a tutorial, but it proved impossible to access with a hack saw much. I wound up desoldering/disconnecting the existing wires from the can leads and connecting them instead to the new electrolytics.

Should I had attempted to rewire it to better match the original schematic instead of how it was acquired? How strange is it for C2-B to have not had anything connected to its positive lead? I do notice that there was some solder on C2-B connector, suggesting that at one point there did exist some wiring there. Not sure what my next step should be. I have one spare tube for that from the original that tested okay but am afraid to even try it knowing it could blow immediately again due to some connection trouble. Also can't reconnect the wiring to the original can since I cut/punctured it trying to remove it to use the base for mounting the new ones.


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File comment: C2-B
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File comment: C2-C
C2-C-Schematic.JPG
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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Sep Sun 01, 2019 3:49 pm 
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Wow. A lot to unpack.
Next time you find a problem where something does not match, or similar, ask for advice here before you act.
You might be in the wrong house.

That being said, you usually can't go wrong connecting things the way you found them. Mistakes can be found in SAMS from time to time.
Are you sure the values of C2 were what they should have been? Maybe SAMS confused C1 and C2. It is always a good idea to double check such things.
Several possibilities occur to me. You weren't where you thought you were. Someone modified the set in an attempt to get it to work better. SAMS has some mistakes. You made a connection mistake.

If the damper is dead it will kill the H.V. and so would not get anything on the screen.
It doesn't seem like there is much connection between C2 and the horizontal section but C4 and C2 are in series in a fashion. I don't have the whole schematic but I wonder if the line feeding that combination comes from the horizontal section. What if C4 was the old cap and that it was shorted, also the old C2 section was open. When you replaced C2 it could have caused too much AC current to flow because of the old C4, and effect the horizontal section.
C2 does connect (or should) directly to the video output tube, so a problem could kill the video signal and you could get a grey screen.
I would trace everything down and check your work.

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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Sep Sun 01, 2019 5:13 pm 
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Look at.the old cap and see what is printed on it. With the circuit changes you are seeing, the can may have different value caps in it. It may just be that they rearranged what caps went in what can.

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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Sep Sun 01, 2019 7:39 pm 
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schematic not matching the wiring then stop and do your homework. i have the riders for this set so if you want i can email it to you. compare the wiring on the two schematics and see if they match. if they do your set is miswired and in my opinion should be put back to the factory wiring shown on the schematic. if the riders shows the connections in your set then go with the riders.

re open terminal on c2 this sounds like it could be a repair trick. if one section of a can cap was bad but the rest is good unsolder the wire from the bad section and replace it with a new cap connected in its place. only way to know is trace the circuit that connects to the open terminal and see if a cap was put in its place. sometime the tec would just bridge across the terminal to ground of the defective cap section with a new one. this can not be done if the defective section is shorted.

there are some can caps being manufactured today and can be purchased at antique electronic supply. very limited values though. if they have the values you need this is the easiest way to replace a can cap.

when you said you had no terminal strip when you replaced the caps it isnt good to have them floating in the air. to much chance of something moving around and shorting. you can tie the negative leads to the negative terminal of the old can. this will at least give it some stability.


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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Sep Mon 02, 2019 1:54 am 
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Quote:
i have the riders for this set so if you want i can email it to you. compare the wiring on the two schematics and see if they match.

That would be great, I will send you a PM.

I agree that I should had waited on this one before attempting replacements when things weren't matching up to the schematic and with some other standard caps still needing replacing that I'm still awaiting replacements for (for the record I did previously replace C3, C4 and C5 electrolytics). I do have some terminal strips on their way that should make things easier to manage.

I find it extremely difficult to get solder to stick to the raw chassis for ground locations or adhering items such as a terminal strip to it. I have tried sanding the chassis, heating gun as high as 850° and applying flux but the solder just falls off. I am using a Hakko FX888D (70W) gun but just a pencil tip and 63/37 solder, maybe a chisel tip would help? I am sure I can find more tips and tricks about doing so online, I just haven't researched that much since most of my activities have been soldering to existing points. I may practice on a old computer case.

I double-checked the inscribed ratings on the can and they match what is indicated in the schematic (60-200 SQUARE, 5-200 TRIANGLE, 20-50 BLANK). It also notes "CAN COM NEG" so the can itself acts as the negative. When I connected the negatives to the new electrolytics, I did solder the end point to one of the existing 'ground' leads off the can which seemed like a good spot since I was having trouble getting solder to stick to the chassis directly. However, due to my earlier messing trying to remove the can to use its base for the new ones, it had come a bit loose from the chassis so there is a chance the ground was not making 100% solid contact.

One component I forgot to mention in my prior post is that there is a 820Ω resistor (R85) from the Vertical Linearity (R5) control to ground on the can (C2), as well as a wire from the Noise Gate (R7) control to the same ground on can. When I redid this, I reconnected these to the same ground peg where the new negatives all tied to. This seems consistent with the schematic but also seems related to why adjusting the vertical linearity would had overblown the vacuum if something is not connected suitably in what i had worked on.

Below is the full schematic and part list for anyone interested, from SAMs.

20Y4E Chassis Schematic (HQ): https://i.imgur.com/uzH0p93.jpg
20Y4E Chassis Part List (HQ): https://i.imgur.com/ZDpj0W5.jpg
20Y4E Chassis Part List Continued (HQ): https://i.imgur.com/soYj4YU.jpg


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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Sep Mon 02, 2019 5:33 am 
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Some TVs used an aluminum chassis...You can't solder aluminum. To get a ground on a aluminum chassis you have to bolt or rivet a solder able steel or copper contact to the chassis and solder to the steel or copper.


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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Sep Mon 02, 2019 8:40 am 
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Soldering directly to a steel chassis requires an 80 or 100 watt iron and a large tip. Yours will not be aluminium, it will be zinc plated steel.

With any soldering, the object has to be heated enough to melt the solder. The chassis sinks the heat away from the tip quite quickly. This is why a gun just won't cut it.

I keep a special large soldering iron just for this purpose.

Oh, with those NOS twist-lug electros, be careful when powering up for the first time. They will need re-forming.
That has been my experience with twist-lugs purchased from the US, because they haven't been manufactured for many years and so have been lying dormant.
I highly recommend you use a dim bulb tester (google it) for at least a few hours, or you could well see your expensive "new" caps explode.

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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Sep Mon 02, 2019 11:36 am 
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Joined: Sep Thu 20, 2018 8:53 pm
Posts: 109
It may be several weeks before I'm able to work more concentrated on this again, due to some upcoming travel and work obligations. A few additional thoughts and updates this weekend:

Reading Material - I stumbled across a great 196 page reference book (PDF) by M. N. Beitman called "Most Often Needed 1956 Television Servicing Information" that includes a 12-page illustrated section on servicing Admiral models and chassis from that era, most of which match or closely relate to mine (20Y4E). This helped me to better understand some of the baseline settings that the adjustments should be set to prior to testing/configuring as well as additional terminology and troubleshooting advice (and if I ever get an oscilloscope will prove beneficial as it includes simple layout and markings of the test points). The full reference is found here and the Admiral-specific section here.

Variac - After meeting with a friend this weekend who does a lot of vintage radio work (who helped test some of the new and old tubes I had ordered), he mentioned the benefits in having a variac to throttle the voltage of vintage equipment. I have only been using a Kill-A-Watt directly from power line in house which measures 123-124V. Since the schematics and measurements are based on 117V I believe a variac may simplify the process of troubleshooting and also be less of a load on the components. I ordered a 5A 0-130V version which should be well-suited for my Admiral (which rates 1.52A at 117V) and other projects. (Anesty TDGC2J-500VA)

High Temperature Soldering Iron - Based on the comments here and other research, I have ordered a 200W-500W variable temperature soldering iron with a wide tip. I could had bought a 100W soldering gun locally for half the cost but I feel this choice makes more sense for my uses including anything that requires soldering to tough materials. (EXSO JY-21500-500W-Stick type)

ESR Capacitor Meter - I already have a usable auto-ranging multimeter and basic capacitance tester (no leakage or load testing, unfortunately). However another facet I was reading about is for ESR testing—which I understand for vintage sets may only be pseudo-useful for electrolytics. But in general it allows another form of testing in-circuit PCB components to get a better indication of anything that may be suspect. I do mess with modern electronics, computers etc. a lot so just feel this may be useful in many cases. I have still been considering a proper capacitor tester for leakage etc. but think that will be a future investment as they are quite expensive. (Signstek MESR-100 V2)

Resistors - To this point I really haven't given resistors much of a thought. At one point I did itemize all of the resistors on the board and found a new 860 piece kit that includes enough to cover almost any of them I'd ever need to replace. I didn't end up ordering it after reading that resistors rarely go bad but have now. The reason being is I tested the R85 mentioned in my prior comment, and instead of reading 820Ω it reads 2KΩ (including with one lead disconnected)! This is the resistor that runs from the Vertical Linearity Control which is what I was adjusting when the damper went out. Could this be the culprit? (Joe Knows Electronics 1/2W 86 Value 860 Piece Resistor Kit)


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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Sep Mon 02, 2019 3:04 pm 
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Joined: Jun Thu 25, 2015 3:21 am
Posts: 1352
a modern cap tester like you mentioned is about useless for leakage or esr testing on any cap found in antique electronics because it just doesnt put enough voltage on the cap to do an accurate test.

what you need for antique electronics is a vintage cap tester like the folowing
https://www.ebay.com/itm/Sprague-TEL-OH ... Sweydc4eZ1

https://www.ebay.com/itm/Vintage-Spragu ... SwI31dXfrq

one thing about them is you wont find an esr test but they do have a power factor test which is basically the same thing, they may need recapping. not to hard to fix. they are under 60 dollars plus shipping.

the 200 watt iron should be fine for soldering to the chassis. if i was you i would drill a small hole through the chassis and get a terminal strip that can be bolted to the chassis. i didnt see what you did but connecting the negative lead of the new caps to the negative terminal on the can should be fine. i never had a soldering station. i used a 75 watt gun for working on point to point wiring and a smaller radio shack gun for pc board work. the small radio shack gun is no longer available. i dont remember the wattage i want to say 45 watts. a 100 or 150 watt gun is good for soldering to a steal chassis. a little no korode soldering paste flux works wonders. not sure if this is still available. it can be bought on ebay now but make sure there is a good amount of the flux left as some people sell the can as a colectable and they are almost empty. dont ask how i found that piece of info its embarasing.

i will get you the riders for your set later today or tommorrow.

a variac in my opinion is a must for working on electronics while some people will disagree the way i was taught to do it is bring the equiptment up slowly on a variac while monitoring current. alternatively you can monitor wattage. this will tell you if you have a short somewhere. a dim bulb tester is also a good thing to have as if you do have a dead short the bulb will limit current flow and save potentially unobtainable parts in the equiptment.

the hookup i would use for this would be variac plugged into the wall dim bulb tester plugged into variac kill a watt plugged into dim bulb tester to monitor current or watts drawn equiptment plugged into kill a watt

most often needed television diagrams will give you the same info you get in sams or riders. all three were collections of service info on different sets by year.


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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Sep Mon 02, 2019 5:17 pm 
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Joined: May Thu 14, 2015 4:15 pm
Posts: 1839
Location: Dallas, TX
Matt, I think that you might be getting conflicting information. You have to keep in mind that repair advice
that was written for equipment that was half a dozen years old does not always apply to vintage equipment 60 years old. " Resistors rarely go bad" might be true for a TV five years old, but 50 year old resistors often drift.
A radio or TV that was only five years old that is having a problem would likely be a tube, but in a vintage unit the electrolytic caps and paper caps are most likely. Bad electrolytic capacitor have the most potential to damage other parts so they should be replaced first, then the paper caps. Off value resistors can cause many problems, but the radio or TV at least works to some degree. A few old resistor types like "candohm" can short and cause serious problems or damage. There is always a possibility that transformers, coils, tubes, switches and wiring can cause problems.
I also would be careful of things seen on Youtube. There is very little oversight there, anyone can put anything on it and no one is going to force bad info to be removed. Bob Anderson's videos are one reliable source of info.
There are a few books currently published that deal with restoring vintage radios but I haven't found any about vintage TVs.
You seems to be willing to spend more than some others that are starting on doing this type of work.
Most of the time I avoid soldering a new spot to the chassis. The important aspect is a higher wattage not a higher temperature. I don't waste time and effort testing electrolytic or paper caps. Usually I don't even apply power until I replace the caps.

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It's not the Destination, It's the Journey.


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