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Old 07-04-2018, 06:00 PM
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compucat compucat is offline
1949 Motorola 9VT1
 
Join Date: Apr 2005
Location: Suffolk, VA
Posts: 950
I pulled the chassis today. After partially dismantling the high voltage cage, I found the trouble. A hole had burned into the hv rectifier filament wire. I found another wire in a box of Zenith roundie parts and installed it. I also replaced the 1.5k resistor with a 1k since it is all I had. The high voltage came right back up with no arcing. I put the set back together and checked the high voltage. It was a 30kv presumably because of the resistor replacement. I turned it down to 25kv as recommended in the Sams. Now for a new problem. The horizontal hold will not lock. I suspect the afc diodes because it will operate throughout the range of the horizontal hold control but at center it will not lock in. I have been having trouble up to this point where the horizontal hold would drift especially after being on for a half hour or more and would have to be set further toward the end of the control range to bring it in. I don’t have any diodes to replace them with so I will have to wait until I can order them. I did replace the 6U10 horizontal osc, afc and discharge tube to no affect. I am just glad the flyback did not fail.
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