Thread: 21zp4a crt sub
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Old 03-30-2025, 02:37 PM
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bandersen bandersen is offline
RCA 741PCS
 
Join Date: Mar 2009
Location: Chicago, IL
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Adjustingthe horizontal freq. & drive, use fresh tubes, recap etc. Make sure B+ is where it should be.

The focus voltage is probably derived from the boost voltage which comes from the flyback damper circuit. So, if you have low HV, the boost * focus voltage are probably low.

You really need a schematic. What model # is it?
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