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Old 06-30-2017, 11:12 AM
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SwizzyMan SwizzyMan is offline
Restoring an admiral c322
 
Join Date: Apr 2015
Location: Side Lake Mn
Posts: 886
Quote:
Originally Posted by Phil Nelson View Post
That's what I had hoped, too, but video injection is not as simple on the CTC-4 as in typical BW sets. The last two sections in the article at https://antiqueradio.org/RCACTC-4ColorTelevision.htm discuss this issue.

Executive summary: video injection requires adding a video preamp as described in the 1956 RCA Broadcast News article. I did breadboard such a preamp, but version 1.0 was disappointing and I set the project aside to work on other stuff for a while.

On the positive side, those are pretty true-looking color bars. You are not far from having a very watchable CTC-4. The edge convergence might never be as good as the center convergence, but that's common in early color roundies. Whichever manual you follow, take Bill's advice -- go step by step in the order shown and do not skip steps.

Phil Nelson
Phil's Old Radios
http://antiqueradio.org/index.html
I had a feeling that it would be a bit more than just injecting a signal into the grid. I originally was under the impression that this was able to be done. Member DaveWM paid a visit to my place and suggested that I should try this. Not sure if he knew that there was more to it than just injecting a direct video source. Or hopefully he was right? He has worked on a couple early color sets so maybe he was on to something?
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Admiral C322C2 Regent (Restoring)
RCA CTC-7 Pensbury (Restored)
RCA CTC-5 Westcott (Restored)
CRA CTC--4 Director 21 (Restoring)
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