Sylvania console - Page 8 - Videokarma.org TV - Video

DaveWM · #**106** 02-03-2010, 08:26 PM

pics of the stereo and TT.

When I was hooking up the TT I noticed the CRT filament glowing dim, must have one of those instant on features. I will have to look into how to disable it. The Stereo has a "main power" which up to now I did not know its function since there was also a stereo power switch as well. Since the TV chassis plugs into an outlet that comes from the stereo, perhaps that will do it, turn off the main power and see if the CRT goes dark when the TV is off.

Findm-Keepm · #**107** 02-03-2010, 10:13 PM

See one of my earlier posts - Sylvania liked to use one section of the on-off switch for insta-on functions. Later models used a diode matrix to merely drop some of the voltage to the tube when the set was off.

Should be easy to rewire - some had a "vacation" switch on the back of the set that turned off the insta-on feature when it wasn't needed/wanted.

Cheers,

DaveWM · #**108** 02-04-2010, 09:23 AM

Watched it some more last night (Rockford) geez it has a nice pic, but the cabinet is so B ugly....

I would like to build a custom cabinet and just keep the TV in a much smaller package.

I know its frankenstien but man its tough to look at.

Charlie · #**109** 02-04-2010, 09:50 AM

Quote:

Originally Posted by DaveWM

...but the cabinet is so B ugly....

I would like to build a custom cabinet and just keep the TV in a much smaller package.

I know its frankenstien but man its tough to look at.

It's not really ugly... it's just... well let's say it a bit exotic!!

DaveWM · #**110** 02-04-2010, 10:04 AM

DaveWM · #**111** 02-04-2010, 11:16 PM

pulled the chassis, wow that was easy, checked two of the cans, both 100-150uf at 200-250v. Both of them checked fine for value and leakage so I will leave them be. I will pull the 1000-1500 50v can and restuff it. I know one section for sure is bad (that is the one that was causing the hum bars).

There is what looks like a motor start can cap (oval shape with odd connectors). Not sure what it is.

I was toying with the idea of removing and re heat sinking the HOT, what do you guys think?

Lastly I did some work on that deflection board mount rail. It uses pins that insert thru a plastic rail. The CRT board pins were loose, the rail had broken. Its ok as long as you dont pull the board for service but I did not like that idea and since I had the chassis out it seemed like a good idea to deal with it.

I was able to bone saw out some "doner" plastic mounts, I just cut them flush up on the rail 3 in a row. I then cut out and cleand up the rail where the busted mounts were. Next I made up a small wood support that lock in the doner plastic to the existing rails, providing both alignment and glue surface. I seems to be solid now, I am letting the glue set up over night. I will try removing the board to see how well it all works tomorrow (assuming I did not manage to glue the board in place).

I am still leaning toward building a custom box for the tv, I just can stand the plastic faux wood inserts on the speaker. Fake wood, well that pretty much sizes up the whole of the 70's...

I will say one thing even though the cabinet bites, I cant say anything bad about this chassis (well other than the plastic rails failing).

Oh and I watched it some more, seems the purity is getting better, my guess is the auto degausser must be improving it.

radiotvnut · #**112** 02-05-2010, 12:29 AM

You're doing the right thing by replacing every section in that can cap. I can remember twice that I tried to skimp by only replacing the one bad section in a dual section cap. In both cases, the other section opened within a week of replacing the first section. Now, I replace all sections, regardless of condition.

I don't know quite how it works; but, that oval cap is connected to the power transformer in some sort of way, which regulates the voltage. Zenith, RCA, Wells-Gardner, and others used that set-up during the '70's. And, I have seen those caps dead short and trip the CB in several Zenith CCII TV's.

Findm-Keepm · #**113** 02-05-2010, 08:51 AM

Quote:

Originally Posted by radiotvnut

I don't know quite how it works; but, that oval cap is connected to the power transformer in some sort of way, which regulates the voltage. Zenith, RCA, Wells-Gardner, and others used that set-up during the '70's. And, I have seen those caps dead short and trip the CB in several Zenith CCII TV's.

It's called Ferroresonance - the cap is there to help regulate the output voltage over wide voltage swings. Rather than regulate each supply in the CCII, Zenith chose to regulate upstream at the transformer.

Ferroresonant transformers are more common in industrial power supplies.

Cheers,

DaveWM · #**114** 02-05-2010, 09:58 AM

3.5 uf NP 440v connected across the secondary of the power Xformer.

I assume its ok so will leave it be (or should I check it with my cap tester).
any idea on the relialbity of these?

looks like if it shorted it could take out the xformer if the breaker did not cut out quick enough.

*zenithfan1* · #**115** 02-05-2010, 11:18 AM

Quote:

Originally Posted by Findm-Keepm

It's called Ferroresonance - the cap is there to help regulate the output voltage over wide voltage swings. Rather than regulate each supply in the CCII, Zenith chose to regulate upstream at the transformer.

Ferroresonant transformers are more common in industrial power supplies.

Cheers,

Cool, I learned something new today. Thanks!

DaveWM · #**116** 02-05-2010, 11:55 AM

Tested the value ok, but for leakage not ok. If it switch the cap tester to the electrolytic Selection then the leak test is ok.

I am gong to leave it alone, esp since all the replacements I have found (Dayton) have an origin of China.

DaveWM · #**117** 02-06-2010, 07:57 PM

Replaced the two LV power supply caps (the two in the one can, 1500uf 50v). I also went thru the IF board and replaced a few out of spec resistors and a few 1uf caps that were just high on the power factor setting of my cap checker (think that is the same as a higher than norma ESR).

the picture is easy the best color of any of my home sets, don't know how but it seems the old CRTs have better color than the later gen CRTs.

I love the fact that you can pop out a whole board by undoing 4 screws. I re enforced the IF board mounting rail it to was cracking up but I was able to save with with out the major surgery requried by the deflection board.

I am leaning toward the custom cabinet, and for sound I will use either a stereo (I have a Fisher 400, Kenwood 44, or an Allied 333) and some nice vintage speakers (wharfedales 60's or KLH 21's). Or a may just do the custom cab (just a nice veneered box) and set it on top of my Magnavox Astro sonic then when watching color I will just turn on the top color set, B&W use the Maggie, but use the astro for stereo sound either way.

ctc17 · #**118** 02-06-2010, 08:31 PM

I though those oil filled caps were for power factor correction? I know thats what they are used for in electric motors. They never short, only open and the motors run current goes up. They also use them in HID lighting ballasts.
I guess it makes sense though, I remember something I had used a SOLA constant voltage transformer like that.

I think you should leave this one all stock and get going on that beautiful Zenith combo you got. That should be your start show piece.

DaveWM · #**119** 02-06-2010, 08:49 PM

Indeed that Zenith has a siren song going...

I also hae a Zentih (same chassis) that is just at TV in a very attractive cabinet. that one was playing (only needed a focus rectifier) and a shot of rejuv on the red gun. I will need to go thru it and check some of the paper caps (the HV kind in the hard white tubes) and it needed a slight touch up on convergence, but I could get that one going very quickly, and get it in the house somewhere.

I also have a CTC-17 combo, not as nice a cab or stereo as the zenith.

My biggest problme is space, I have taken over 1/2 the garage, I need to figure out a way to get some of these in the house so I can get my Exp back inside.

I sorta want to go it this order:

1. B&W Maggie, 23" all tube combo, just needs the vert integrater (I think, it has interlace problems).

2. Zentih TV only Color late 60's couple caps and a touch up of the convergence

3. Zenith combo color late 60's tube TV nice SS receiver (CRT tested that is the extent of my work on this one, no power up, have not touched)

4. RCA combo, OK cab (dirty grungy front panel) CTC17 (same status of 3 CRT test only)

5. RCA roundie (this one will need a new cabinet, the old one was infested with termites, LOTSA damage to the wood. The pictrue is near perfect, this one had a shorted vert output and a few minor things but that was the only real problem.

I am prioitizing by the ones that will take the least time to get knocked out, rahter than the ones that interst me the most.

Of course this is busy time of year for me at work so its kinda having to take a bit of a back burner for a while.

Reece · #**120** 02-07-2010, 11:35 AM

Dave wrote: I was toying with the idea of removing and re heat sinking the HOT, what do you guys think?

I would do it. I had a 1979 Sylvania console that liked to eat HOT's so I regooped the heatsink and added some more aluminum fins to it and that worked well.