The middle pin of the HOT on a K7000 reads short

Black Matrix

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Hey all,
I've got a K7000 chassis that seems to have the middle pin of the HOT reading shorted to the other 2. I don't think this is normal...and was just wandering if anyone had any thoughts as to what might be causing it. I pulled the HOT to replace it with a new one (although the old one read fine to the best of my knowledge). The middle pin reads shorted even with no HOT installed. Could a bad Critical Cap cause this. It also had a blown fuse. Wanted to make sure this wasn't some other problem before I put power back to it. I also don't think the IC-4 is bad although I may change it just to make sure. The pin being shorted just has me a bit worried. Any ideas?
 
Is this a 19" or a 25" chassis? Also which voltage regulator STR30123, STR3123, STR30130 or STR3130? Which pins to look for a short on will depend on which voltage regulator. Yes the critical safety cap can cause there to be a short on the B+ along with other poly caps in the horizontal circuit.
 
It's a 19" K7600 chassis. I believe it's the larger sized voltage regulator STR-3123 I think. Which poly caps should I be looking at. Could the LIN Coil cause this. It looks like its seen better days. Thanks in advance.
 
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It's a 19" K7600 chassis. I believe it's the larger voltage regulator STR-3123 I think. Which poly caps should I be looking at. Could the LIN Coil cause this. It looks like its seen better days. Thanks in advance.
 
those linearity coils can break, but as long as the copper is still connected to the pins they should be fine. you can tack it back together with silicone if need be.

C38 should be replaced. there's something in there that can drag R101 down, which can cause B+ issues. probably advised to change out C36 and R101 while you're at it -- potentially R89.
 
I appears to be a bad Critical Safety Cap at C36. Its blue, has 4 legs and tests shorted across between both sets of pins....the ones closest to each other. Posting now to find a good source.
 
the 2 legs that are closest to each other on a 4 legged C36 cap are the same leg connected inside the cap.

they will always read shorted.

Peace
Buffett
 
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