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Old 06-13-2017, 12:31 PM
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DavGoodlin DavGoodlin is offline
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Join Date: Aug 2011
Location: near Strasburg PA
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Quote:
Originally Posted by Jeffhs View Post
Did you check the CRT? This could be the reason for the dim raster, although I would look elsewhere first. The horizontal output tube could be so weak it is just barely working. In a set this old (late 1940s-early 1950s), this seems very likely, but again, I would check the CRT cathode emission before doing anything drastic. Of course, if the set is using a CRT brightener, the tube is just about shot anyway and should be replaced.
Yes, the 12RP4 had a bright-ner on it and tests weak. I also get red plate on the video amp 12AU7 when I turn up to contrast control.
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