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Old 09-17-2011, 01:31 AM
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miniman82 miniman82 is offline
First Light: 1952-2011
 
Join Date: Jun 2009
Location: Great Mills, MD
Posts: 4,174
I'm beginning to notice there are some issues with the horizontal oscillator. Pin 5 is right where it should be at 270, but the grid is sitting at -65 when it should be around -85. This in theory would cause the tube to conduct harder, leading to an increase in output waveform, which could in turn overdrive the HOT. This makes sense, since I'm no longer able to get rid of the drive lines in the screen even with the drive control all the way at minimum. There is a cap (C236 in the RCA manual) connected between terminal F on the hor osc sweep trans and tube pin 4 (grid) that if leaky, could cause this rise in grid voltage. Tomorrow, I'll see if I can find me a sub. This is exactly why I never trust these old micas, nothing but trouble and headaches if you leave them in.
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