10-01-2023, 01:11 PM
(10-01-2023, 12:07 PM)chriswood Wrote: I was wondering if the Mullard EHT unit used in the early 50s projection TVs would qualify as switch mode, it seems to have the essentials found in switch mode units.
Chris
In a sense I guess it is. The repetition rate of the pulses supplied to the voltage tripler diodes varies according to the beam current of the CRT, although I'm not sure if the pulse amplitude remains level.
In the BRC 3000 switched mode power supply line timebase pulses are supplied to a monostable and the mark space ratio of the chopper drive pulse depends on the current and voltage demands of the timebases. SMPSU supplies 55 to 63volts.
Geordie McBoyne.
