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Working on my RCA 21D645 KCS97 again
Since my work on my Admiral 12X12 went fairly well, I feel like I may be able to tackle this problem again. Back in early 2018 I started working on restoring an RCA 21D645, the first antique television I ever worked on. I had someone who was helping me learn how to work on these sets, but eventually he just didn't have the time to help anymore. I then started working on it again during quarantine back in March of 2020, and I made the stupid mistake of replacing all the paper capacitors in the set at once without regularly checking if the set worked, and I didn't take any photographs either. After looking over the set I noticed one capacitor on the audio board had not been properly soldered, and after making sure it was secure I was able to get the audio back, but still no video signal. There is a raster on the screen, and I noticed that the 6AQ5 video output tube and the 6AW8 video amplification tube were not lighting up when the set turned on, and removing them had no effect on the set, moving them around in their sockets also did nothing. All the other tubes lit up just fine. I tested all the tubes in my tube tester and aside from one bad 6U8 with a short (which I replaced) the rest of them tested well enough that they should at least produce some kind of picture (some had weaker emissions). I checked all the capacitors on the video board and none of them seemed loose or disconnected. I've gone over the schematic several times, and quite honestly this would've been a million times easier if I had taken a reference photo all the way back before I replaced the capacitors, I learned from this mistake when working on the Admiral. I have the photofact and the RCA service manual for this chassis and while they do help quite a bit, the photo of the chassis in the photofact is incredibly grainy and its hard to make out the leads on some of the capacitors that aren't installed on the circuit boards. If there is any way someone could either take or direct me to a clear reference photo of the underside of a KCS97 chassis, I would be incredibly grateful.
Last edited by rca21d645; 02-03-2021 at 10:05 PM.
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