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Old 06-05-2012, 10:15 PM
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miniman82 miniman82 is offline
First Light: 1952-2011
 
Join Date: Jun 2009
Location: Great Mills, MD
Posts: 4,183
Well, there's your problem! 110VAC is not enough, RCA specified 115VAC as the input voltage, but 117 wouldn't be unreasonable. Bump the line voltage up, HV should also rise but I would fix the drive line ASAP. I'm a little foggy, but I think mine put out 23kv with no regulator. Excessive drive can cause horizontal cathode current to spike, so run through the horizontal setup procedure. Adjust H-lin, width, drive and HV then see what the picture looks like. You'll probably have to do them several times through, since they affect each other to some extent.

Hint: before you measure across the resistor in the cathode of the horizontal output tube to get the current, measure its resistance with an accurate meter. I promise it's not the same value called out in the schematic, due purely to age. That will cause your current calculation to be skewed. Once you have the (actual) resistance, read voltage across it and plug those values into ohm's law. I got something like 140-160ma on my set.
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