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Old 06-13-2017, 11:44 AM
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DavGoodlin DavGoodlin is offline
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Hallicrafters 602 acquired

12 inch round, a big screen for a Hallicrafters anyway and also unlike the famed push-button models, has some kind of continuous tuner that rotates between detents for channels.

This set was found in an attic of a house in the heart of coal country (initially served by only one VHF channel until UHF stations popped up in 1952-3) and brought to work by a friend of the original owner. I had been working on it over lunch-breaks where he and I replaced all the wax-paper and electrolytics. Since he is out on extended disability, he asked me to just take it home.

From VintagePC's thread on his Hally 815, I deduced there are quite a few issues beyond just the caps in this set as well. We did get a very dim but full raster, so its not hopeless but it has some funny symptoms.
IMG_8192.jpg
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Last edited by DavGoodlin; 06-13-2017 at 11:48 AM.
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Old 06-13-2017, 12:28 PM
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Jeffhs Jeffhs is offline
<----Zenith C845
 
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Quote:
Originally Posted by DavGoodlin View Post
12 inch round, a big screen for a Hallicrafters anyway and also unlike the famed push-button models, has some kind of continuous tuner that rotates between detents for channels.

This set was found in an attic of a house in the heart of coal country (initially served by only one VHF channel until UHF stations popped up in 1952-3) and brought to work by a friend of the original owner. I had been working on it over lunch-breaks where he and I replaced all the wax-paper and electrolytics. Since he is out on extended disability, he asked me to just take it home.

From VintagePC's thread on his Hally 815, I deduced there are quite a few issues beyond just the caps in this set as well. We did get a very dim but full raster, so its not hopeless but it has some funny symptoms.
Attachment 194916
What other symptoms is the set exhibiting, and did you check the CRT? The latter 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.
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Old 06-13-2017, 12:31 PM
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DavGoodlin DavGoodlin is offline
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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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