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Toshiba TV problem?

I have a 32 inch Toshiba TV (CX32D60) vintage 1994. It developed a problem with the vertical aspect of the picture. It started after a local power failure. I, in my infinite wisdom, ran an extension cord out to the car and plugged it into a small inverter. Anywhooo ... now, when turned on, the lower six inches or so stays black until warmed up and then about the bottom few inches stays black. People on the screen look like cone head midgets. I'm a DIY type person ... do all of my own mechanical work on the cars and build my own computers etc. but don't know squat about TVs. I hate to toss it, without at least popping it open and having a look, and am sure not about to lug it down to a repair shop or pay to have it fixed ... especially considering how old it is. I somehow feel that I would get screwed in the deal, like a woman taking her car down to "Bubba's Auto repair" and being told that her muffler bearings are shot and need to be replaced. I've Googled around some and have come up with a few things. One is that you can get the shit shocked out of you, even though it's unplugged. I'm not sure where and what exactly has to be discharged before tinkering. Any tips on that would be appreciated and any thought as to what the problem with it is. I do have a digital volt meter. I came up with this on a web page about TV repair: Vertical squashed "This is a vertical deflection problem - possibly a bad capacitor, bad connection, flyback/pumpup diode, or other component. None of these should be very expensive (in a relative sort of way).

If the symptoms change - particularly if they become less severe - as the set warms up, a dried up electrolytic capacitor is most likely. If they get worse, it could be a bad semiconductor. Freeze spray or a heat gun may be useful in identifying the defective component.

It is often easiest to substitute a good capacitor for each electrolytic in the vertical output circuit. Look for bad connections (particularly to the deflection yoke), then consider replacing the vertical output IC or transistor(s)."

So, as I said, I don't know shit from Shinola about it but can't let myself throw it out, without at least having a "look see". Sure would appreciate your time and effort for any advice or tips. Thanks in advance

Reply to
Forrest
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Hi,

go to this site and you will get all the info :

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cheers

Reply to
newbee

If You can solder and have access to capacitors then this is likely fixable. 99% of the time what you describe is due to one 20 cent cap!

don't bother with ESR meters unless you plan on fixing tvs regularly,. just change the caps near the frame /vertical IC. there aren't many and they arent expensive. look for a small ish IC, usually on a metal heat sink with anything from 6 legs. ( older sets used a pair of transistors but this is doubtful in your case).

tip: if the ic is labelled say IC 401, then change all the nearby caps similarly labelled , eg c405 c408 etc etc. do them one at a time so you don't mix them up. good luck

-b

Reply to
b

Thanks for the replies and advice but I haven't quite figured out how to start without either killing myself or trashing the TV. One or two things I've read say to just short out the caps and picture tube. Then I read all this stuff about using certain resistors to do it. Like this:

For the CRT, use a high wattage (not for power but to hold off the high voltage which could jump across a tiny 1/4 watt job) resistor of a 1 to 10 M ohms discharged to the chassis ground connected to the outside of the CRT - NOT SIGNAL GROUND ON THE MAIN BOARD as you may damage sensitive circuitry.

Do I need to go to an electronics store and buy some resistors before I start and if so what do I want?

Reply to
Forrest

On Jan 8, 4:56 am, "Forrest"

that is just overkill. unless youre planning to remove the big line transformer then you needn't short out anything. just leave the set unplugged for a few hours or even overnight and you will be fine, just don't touch the big red wire going to the sucker on the tube!

Reply to
b

M
-

More important than the resistors, I think, is to have something that will allow you to safely make electrical contact with the high voltage clip on the tube. This is usually under a large, rubber-like cap. You need something that will allow you to poke under that cap and touch the clip while electrically insulating you from high voltage, also bearing in mind that you're scraping against a glass tube (so it shouldn't have any sharp edges). Obviously (I hope) a long screwdriver is out, since its metal shaft would be bringing the high voltage charge close to your hand. All sets probably use built-in discharge circuits, but I never trust those - I just feel safer knowing I've discharged the tube myself.

Reply to
Mr. Land

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