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VA561 05-30-2014 10:05 PM

Expertise Needed
 
5 Attachment(s)
I hope someone at videokarma can share their knowledge/experience to help repair this set. I have a 1959-60 Sylvania halolight tv, model 21C09W. As I am a relative beginner with this hobby, I took the set to a friend of mine who operates a tv repair shop. I first had the tubes tested and one turned up shorted (5T8). After installing the tubes, he used a variac to try to slowly power the set up. No picture, no sound. He then found a fusible link that was blown.After repairing that problem, the set was slowly powered up and we had sound and the picture that is attached below. He diagnosed a vertical issue with the set and checked all of the caps and resistors in the vertical circuit. I highlighted on the schematic all of the caps /resistors that were checked and replaced if bad.

The problem is still not solved. In his opinion, the only potential problem areas related to the vertical issue are a defective vertical transformer and/or yoke. Advice would be appreciated.

Kamakiri 05-30-2014 10:57 PM

1 Attachment(s)
I did a Halolight 21C611M last year that ended up being quite a handful. The base recap on the upper chassis board, though, was actually kind of fun. Here's a pic of the one that I restored, from the back, and laying down.

If the set's something that you plan on keeping and enjoying for a long time, a full recap is the first thing I'd do. But beyond that, I don't think it's the yoke because you don't have a discernable picture even if it's really short (I assume that you hooked it up to a source to test that). A bad yoke will usually yield some kind of picture even when the vertical sweep is mostly collapsed.

Seeing your scan lines doubling up and all over the place to me points to the vertical output transformer, but maybe someone else can chime in and verify what I'm thinking.....

rca2000 05-30-2014 11:07 PM

This may be a dumb question--but did your guy REPLACE the filter capacitors in the POWER SUPPLY? I do NOT see any marked on your manual. They ARE bad by now--those ones off of the 2 doubler diodes in the power supply. No doubt if they have not been replaced--you have low B+ along with a host of other problems.

Kamakiri 05-31-2014 01:29 AM

If that's the same chassis setup, which I suspect it is, this is what I had to go through just to do the filters (and do them right)

http://www.videokarma.org/showthread.php?t=259581

VA561 05-31-2014 08:10 AM

One of big caps was replaced , the other checked good so we let it alone for the moment. At least until we fix the current problem. We are using a vcr as the video source.

miniman82 05-31-2014 08:52 AM

PM me your address, I can stop by tomorrow.

zeno 05-31-2014 05:08 PM

Halos are just before my time but the pix sure has a bad
transformer look to it. As for testing the caps the best & most
accurate test is a NEW cap. You may want to recap the
vert before trying to find a VOT for this beast. Also if you
got an analyst unhook the transformer & just drive that. Should
get a much more normal sweep ( but not perfect) if the prob is behind it.
As for the main filter cans although they are probably in need of
changing the pix is full width & no apparent hum bars. Best to start
with the worst problems & be sure to find them before doing
all the preventative stuff & total recaps etc.........

73 Zeno:smoke:

ggregg 05-31-2014 05:34 PM

At least change out the electrolytics even if they test good. I wouldn't trust them at all, especially the ones in this set. Just replace them. Neither of mine had any type of raster and both worked well, and still do, after a full electrolytic and paper recap.

Take Nick up on his offer. He'll get you on the right track.

Notimetolooz 06-01-2014 12:09 AM

Besides the vertical, you probably have video and horizontal sync problems.
The vertical seems to be a possible show stopper however.


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