|
Well, tonight I finally got to make a DIY variac per radiotvnut's suggestion, so here is what I found:
I started out with a 75W light bulb in series with the TV set. The first couple of times pushing the power button the light bulb came on brightly then went off quickly, accompanied by one clicking sound inside the TV per push of the button. The third time, The TV came on and tried to stay on, but clicked off after about 2 or 3 seconds. The bulb lit up simultaneously and continually dimmed in the same period, and then went out. The fourth time, the set came on and stayed on, with the screen reaching full brightness and the speaker outputting static (the set was on a blank channel). The set continued to stay on, but the screen was flickering, bending, and rolling badly, and the light bulb was dimming up and down. Pressing the channel button made it worse, to the point that it was almost completely shutting off in between flickers. I assumed that this was due to the voltage being too low, and so swapped the 75W bulb out for a 100W.
With the 100 watt-er, the first couple of times the set clicked on and off, third time it came on and shut off after 3 seconds, and the fourth time it came on and stayed on. This time, the screen was much less distorted while nothing was being pressed, though I noticed that the volume went down ever so slightly while it was just sitting there. The light bulb remained in a steady, half-way dimmed state. Pressing the channel button sent the unit back into it's flickering, distorted mode, with the set alternating between a twisted, flickering screen and nearly shutting down; the light bulb dimmed and brightened during this time as well.
Just for reference, I plugged the set into the wall, bypassing the variac, to compare results. Plugged straight into the wall, the set would come on, stay on with volume, but the second I press the channel button it shut right off. A few weeks ago it wouldn't even stay on, so I'm not sure why tonight it stayed on until I pressed the channel button (the only thing I can say is that it was unplugged for the last two weeks).
Anyway, this is the info I currently have. I did look at the board again before I put the case back on for testing, and I did not see any noticeable bulging or crease breaks in the caps. I'm still going to look into new caps though, since I definitely smelt that ammonia smell when the set was first in my possession.
|