83 GE 25" Console on the Fritz!

[AshTray900]

I have an 83 model ge console tv that is acting up. the video signal is blanking on the top from time to time and pinching in and wiggling. sometimes it seems to draw down to the bottom portion of the tv and pops in and out. static picture is 100% fine. I recently took both parts of the tuner out. checked for bad solder joints. resoldered a bunch of poor looking candidates and actually got a dead led digit back on and the problem seemed to have gone away. I am trying to narrow down my search so I don't spend two weeks checking capacitors like I did on my 73 zenith chromacolor.

I assume hv and vertical / horizontal output to be ok since static picture has no problems. is this a correct assumption?

I have no color issues during the problem, im thinking I still have an issue in the tuner somewhere but im not sure, its broken down into two parts, its a digital set and one part mounts up by the controls and the other is down next to the main chassis. im hoping someone might have seen this before and can give me a hand. sometimes changing the channel up one and back down one stops it for awhile. I have tried on both channel 4 and 3 and same results. will try to post a youtube video of the issue if the site will allow

this isn't the common vertical problem ive seen in these sets where the picture drops down an inch or two then blows a resistor, this set has already been serviced for that issue before I got it back in 97 as I can tell the culprits have been replaced. Any advice would be greatly appreciated http://youtu.be/J32vi6HFsgg

im sure I can fix it but id rather not spend weeks troubleshooting or a few hundred dollars for a complete recap when im not sure that is the real issue.

[AshTray900]

http://youtu.be/J32vi6HFsgg

[zeno]

If its an EC or EM chassis its almost always cold
joints on the griplets. Almost nothing else went on them.

73 Zeno

[AshTray900]

Well turns out when I cranked the brightness up it did the same thing on the static too. C904 was replaced in the past with two 47uf caps instead of a single 100uf cap one had blown. Had one in stock luck has it rated at the high voltage of 250v set called for atleast 160v. Problem looks gone now but only time will tell! C904 on this chassis must be a common problem. It was related to the other issue I was wrong. Didnt figure it would have been replaced with a makeshift cap and thats most likely why it behaved as it did instead of just shorting out the vertical all together

[radiotvnut]

Sounds like you have a "PC" chassis set. The most common problems were the 100uf cap in the vertical circuit failing. Early productions used a 50V capacitor, later productions used a 63V capacitor; but, both types are high failure. When I fixed these sets, I always used a 100V high temperature capacitor and I never had any callbacks. The other common problem is the big 100uf, 160V capacitor that's located at the rear right corner of the chassis, close to the flyback. If this capacitor opens and if the set is left on too long, the horizontal centering control will burn up and the HOT will short. Sometimes, when the centering control burns, you can isolate it's case from the heatsink that it's mounted to and it will work OK. I have also replaced the control with, IIRC, two 250 ohm, 5 watt resistors.

I can't remember the value; but, there is another capacitor in the B+ line to the video output stage that will open and cause one side of the screen to be darker than the other, along with a smeary, streaky picture.

There was one other capacitor in the vertical circuit that gave trouble; but, I can't remember the value. I want to say 10uf and it was close to the yoke plug.

[AshTray900]

It was the 100uf 160v by the flyback. When I pulled the makeshift hunk out I replaced with a single nichicon 100uf 250v cap I happen to have parted out of a usless sony bluray player that sony wouldnt release new firmware for. So far so good.

[AshTray900]

Thanks for the tips I need to print and put with my schematics attached to the black box on the side

[AshTray900]

[AshTray900]

From the looks of it that other cap in the vertical circuit was replaced with a better cap. Maybe orange = high temp?

[AshTray900]

good pic now scanlines seem more stable

[davet753]

Made lots of money replacing caps in those old GE sets. I always close replacements with a much higher voltage rating, and I can't remember ever seeing one come back across my bench again with the same problem. Seems like there was a total of 3 capacitors I usually replaced....I can't remember now.....but I remember charging $60 for a portable and $100 for a console to do it

While I wasn't necessarily a big fan of GE's in the early 1980's, they were actually a pretty dependable TV, and they made a lot of profit for the repair shops.

[AshTray900]

This one just keeps on going. Going to run it till the crt is dead