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Old 02-02-2014, 04:35 PM
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bandersen bandersen is offline
RCA 741PCS
 
Join Date: Mar 2009
Location: Chicago, IL
Posts: 8,808
Here it is cleaned up and ready for rewiring.


Unfortunately, I discovered one of the pins had broken off and been replaced with a bit of bent wire. Not sure what to do about it.



Also spent some time troubleshooting the chassis. It takes several minutes for the horizontal to stabilize and even then it's very touchy.

Also the 410 boost voltage is less than 300.


The horizontal is so touchy just bringing my hand near the tube has an effect.


That got me thinking one of the pins might be floating. Sure enough - pin 2 is open.

There should be a 1Meg resistor between it and pin 7 of the AFC tube. It's buried inside one of the networks so I must have made a mistake somewhere

I tried tacking an external resistor between the tube sockets. It had a definite effect, but now I can't get hold lock at all.
So much as I hate to do it, I'll have to pull the board again.
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Last edited by bandersen; 02-02-2014 at 10:51 PM.
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