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  #24  
Old 01-17-2019, 06:21 PM
Jeff Jeff is offline
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Join Date: Oct 2015
Posts: 32
So I figured it out... Initially I was trying to figure out why I wasn't getting a signal out of pin 5 of the IF amp IC, so I tried some stuff not really worth mentioning... only to find out that pin 3 of the IC was shorted to ground. C140 in the schematic was responsible for the short, and once replaced I was able obtain a good signal out of pin 5. But, the set's picture still displayed the same issues as previously discussed. So, after some probing I found that I had a good signal out of Q200, but basically no signal out of Q205. I replaced Q205 with no change, checked it, and it checked just fine. I then found that R206 on the schematic, which comes out of the emitter of Q205 and goes through an inductor to ground, was practically open, and had a burn spot. Upon replacing it, the set now behaves like I think it should. So how did the resistor burn up? Well, a while back I was trying to directly inject a video signal into this set, which little did I know doesn't play well with a transformerless set. From what I understood, Q200 went POP when the grounded rca cable tip shot 120v through it, then through chassis ground, then through one of the bridge rectifiers (which also blew) to the hot side of the plug. So prior to posting here, I had replaced Q200, and R202, which was between it and chassis ground. What I didn't know was that it also blew R206, which was between Q205 and chassis ground.

TLDR: I blew it up and didn't replace everything that blew.
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