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Old 10-03-2016, 11:00 AM
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DavGoodlin DavGoodlin is offline
Motorola Minion
 
Join Date: Aug 2011
Location: near Strasburg PA
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Quote:
Originally Posted by DaveWM View Post
ok now I remember, the HV is controlled by a horz bias pot which directly bias's the Horz out. So you adj the HV to about 25kv with that pot. The regulation takes place from feedback from the fly. The problem I ran into was the excessive heat (to the point of severe wax melting and even smoke) so adj the bias down to get the heat down resulted in under scanning of the crt. That was resolved with a HV disc cap across the yoke horz windings. Pretty mickey mouse fix that maybe was not the right thing to do. Perhaps it needed a new fly.. whatever just don't leave the set alone (good idea for any 50 year old color tube set). I think I adj to about 23kv
Sylvania used feedback from the fly to regulate pulse amplitude to the HOT grid on this on their later tube and hybrid chassis. Didn't Motorola do it also?

Ill make sure to copy these notes into my "Philco Color TV service manual" a Tab book by Robert L Goodman. I have a 19" chassis version of this set and its fly runs hot.

Few color TVs had a tuning meter or tuning eye tube. The OP's model might have the tuning eye tube. Only GE had a tuning device on their 1967-68 color sets and Westinghouse had that on-screen bar graphic on that one-shot chassis before they quit making Tvs. otherwise, I never saw visual tuning devices on an RCA, Zenith, Mag etc
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Last edited by DavGoodlin; 10-03-2016 at 12:03 PM. Reason: add sylvania note
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