G07: switched out IC and pots, now have vertical collapse

vintagegamer

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G07: switched out IC and pots, now have vertical collapse

Swapped out the IC with a new one and a socket from Bob Roberts, and also swapped out the 4 pots (vert hold, vert lin, vert height, h freq), and now have vertical collapse.

The collapse happened right after doing the IC swap. Did not have it prior. Went through the swap of the 4 pots hoping it would resolve the issue, it didn't.

Please tell me what I did wrong. The viewable area is now about 3" high (you can see the pic area from left to right) in the middle of the monitor screen. Also, the image displayed on it looks upside down and, at times, reversed.

From what I have found so far in research, it's now sounding like the width coil? Why didn't I have that prob prior to the IC swap? Sigh.

EDIT: B+ voltage is at 119.6 btw
 
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Did you install the IC in the correct direction? Double check to make sure there are no bent pins?

If that checks out, check x401 and x402, as well as fr401.

Fr401 is a fusable resister. It should mesure right around 68 ohms. If its open, or way out of spec, it's bad.

X401 and x402 are your vertical output transistors.
 
RESOLVED (well, the vertical issues, that is).

I'm not quite sure what the issue was, but even when I was first installing the socket that came with the IC from Bob Roberts, it just didn't look right. It looked like one of the connectors was bent or not seated properly or something.

Luckily I had a 16-pin gold-plated socket lying around in the garcade from doing other work, I put that one in, reinstalled the chip, reflowed the solder joints at X401 and X402, and I got my vertical back.

The picture on the monitor looks BEAUTIFUL, except for................

(return back to my horizontal jitters thread :( )
 
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