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Old 02-28-2014, 05:50 PM
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Phil Nelson Phil Nelson is offline
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Quote:
Originally Posted by Phil Nelson View Post
No doubt it is something simple
Or maybe not. The no-signal condition persists, as if there's nothing coming out of the tuner. I found that I can connect everything if I stand the chassis on our trusty old cooler. Not convenient, but I'm lacking a workshop at the moment.



Injecting a video signal at the video amp gives me a faint picture.



Injecting an IF signal in the IF strip also gives a (fainter) picture.



Subbing the 6X8 and 6BQ7 tubes in the tuner changes nothing. I still get absolutely nothing from the tuner -- no static/scratching when you change channels, nada.

I guess the next step is to pull the tuner and try some cleaning. I'm still at a loss to see why the signal suddenly disappeared. There are no obviously torn-loose wires, etc.

I posted the Sams manual here for anyone who's curious:

http://antiqueradio.org/art/RCA-CTC4-Sams-314-9.pdf

I believe the schematic from my RCA field service manual is more accurate, but I don't have a scan of that.

Phil Nelson
Phil's Old Radios
http://antiqueradio.org/index.html
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