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Old 08-04-2022, 04:55 PM
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bandersen bandersen is offline
RCA 741PCS
 
Join Date: Mar 2009
Location: Chicago, IL
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It was one of the first CRTs to use electrostatic focus. Much nicer than having a big, clunky electro-magnet on the neck to adjust. Downside is it requires around 3,000 volts.

They got that from a tap on the HV secondary and used the 1V2 to rectify it.

Later design got it down to around 500 volts which they could get from the boost voltage.
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