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Old 16th Feb 2019, 2:42 am   #77
Catkins
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Join Date: Feb 2015
Location: Chepstow, Monmouthshire, UK.
Posts: 234
Default Re: 1938 Murphy A56V television restoration

I spent quite a while replating all the various pieces of metal that needed restoring. Picture 1 is an additional photo of one of the replated brackets on the deflection coils, and shows quite a good mirror surface has been obtained. I have lots more pictures of the replated parts, but, I think it is important to get on with the story.

After doing the plating, I took stock of what I needed to do next. The obvious one was to reassemble the various components that had their metal bits replated. This meant the transformers, the scan coils, the potentiometers, putting the potentiometers back onto their replated mounting brackets etc.

While reassembling the potentiometers, I took the time to test them, and fix any of the potentiometers that didn't work. Some were just dirty, and needed a good clean. Some were discovered to be open-circuit on the resistance track. I used the same trick to fix them, as I did previously with the HMV 904 potentiometers. I used layers of conductive silver paint to join the breaks on the track, which also had the side effect of bringing the over-all resistance back to within tolerance.

Photo 2 shows one of the potentiometers repaired with silver paint. Photo 3 shows the repaired potentiometers replaced on the replated mounting brackets.
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