1992 19" Trinitron - Videokarma.org TV - Video

karmaman · #1 10-22-2009, 09:33 PM

Hello guys, it's been quite a while since I was on here! Last time I visited, Videokarma and Audiokarma were both still one!

Anyhoo, I found a nice little curb TV today. It's a 1992 Sony KV-20TR22. When I plug it in, the standby LED lights but that's it. Any suggestions on what might be wrong or what to check for? I would LOVE to get this going, as I've been wanting a Trinitron for a while now.

karmaman · #2 10-22-2009, 10:13 PM

Update! Big update!! I got it to turn on! After resoldering the flyback, HOT, and a few assorted components in the Horiz. area, it turned on.

However...

It took several tries to make it turn on. It buzzes wildly and takes about a minute to power up. Slapping the area of the board with two relays on it changes the pitch of the buzzing, I think it's a stuck relay. What do you guys think? How do you clean a relay?

EDIT: Forgot to mention, great picture too. It needs a really good degauss (perhaps the thermistor isn't doing it's job?), but the picture is bright and the tube doesn't look like it's weak.

radiotvnut · #3 10-22-2009, 10:54 PM

Look for an electrolytic cap on the order of 47 uf, 250 volts located somewhere around the relay. Several months ago, I rescued an '89 Sony from the salvation army that had a buzzing relay and would not turn on. One new 47 uf cap fixed the problem.

On the degaussing issue, resolder the degaussing thermistor. Very common fault on '80's and '90's era Sony's.

karmaman · #4 10-22-2009, 11:18 PM

Thank you radiotvnut, I'll check that out tomorrow afternoon. I think the thermistor is fine; after I let it sit for a while I turned it back on and I got a beautiful picture.

This thing has a bangin' picture! A quick touch to the focus knob on the flyback made everything razor sharp again, and the colors are spot on. It's got that bright "Trinitron look" to it. Even the convergence and centering are perfect.

I let it sit for almost an hour, and upon plugging it back in, it started buzzing again. I let it buzz for a minute or so, but this time it didn't turn back on, so I unplugged it. I'll replace that cap tomorrow and try again.

Man I've been wanting a Trinitron for a while!

freakaftr8 · #5 10-23-2009, 12:59 AM

Hey karmaman congrats on a repair and troubleshoot well done! I had a 1992 19" trinitron a while back and repaired the same problem. Ended up givind it to my cousin. She says it still wood great 5 years later! Good luck

Findm-Keepm · #6 10-23-2009, 06:18 PM

Quote:

Originally Posted by radiotvnut

Look for an electrolytic cap on the order of 47 uf, 250 volts located somewhere around the relay. Several months ago, I rescued an '89 Sony from the salvation army that had a buzzing relay and would not turn on. One new 47 uf cap fixed the problem.

On the degaussing issue, resolder the degaussing thermistor. Very common fault on '80's and '90's era Sony's.

The ground connections to the tuner were also a problem, as were the connections to the vertical chip. We saw a lot of "post-military-move" Sony sers that only required a resoldering of the big three - degaussing thermistor, vertical chip, and the tuner. Later, JVCs were the solder scrooges.

Cheers,

karmaman · #7 10-23-2009, 07:29 PM

radiotvnut you hit the nail on the head. In mine, it was a 22uf 250v cap. I switched it out and no more relay buzzing!

What do you guys think?

MRX37 · #8 10-23-2009, 08:10 PM

I think you have a good set there.

Nice work getting her going again.

karmaman · #9 10-24-2009, 11:03 AM

Thanks MRX. There's one final problem to solve with this set though.

The colors! The picture is bright, clear, and easy on the eyes, but the colors are really dull. It looks as if somebody turned the "Color" control down. However, with my Sony universal remote, I can't make the menu come up. All I can get is an adjustment for "Hue", which doesn't do much. Is there any way to get the colors to look more vivid? It looks really dull with both my regular cable input and my dvd player.

ChrisW6ATV · #10 10-25-2009, 06:09 PM

Try a different universal remote control, maybe a newer Sony if you can. You should definitely get a full range of adjustments to appear.

karmaman · #11 10-27-2009, 12:33 AM

I bought a brand new Sony universal, but still no cigar :/. I also tried the remote from the 19" Sony LCD I bought my mom a few months back and it controls every aspect of my '92 Trinitron EXCEPT picture control. Ripping my hair out over this one. The only control I can bring up is "HUE".