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Radio Wrangler · 31st Jul 2012, 8:10 am

I'd pick a frequency between 20 and 30 kHz, then you can use a TV line output transformer core, and TV HT rectifier diodes will be fast enough.

10kHz risks making the thing irritatingly audible.

Back in the 1960s I used to use a 50Hz iron 400-0-400 transformer driving a Cockroft-Walton multiplier (the circuit posted in number 72, above) to make -2kV for my VCR97 tube. The capacitors were 0.1uF and about 50mm diameter by 150mm long. I never thought of a high frequency oscillator. It would have made things a lot simpler, and I'd taken a lot of dead TVs apart for the components. I must have been stupid. All the clues were there.

Cheers
David

31st Jul 2012, 8:10 am	#74
Radio Wrangler Moderator Join Date: Mar 2012 Location: Fife, Scotland, UK. Posts: 22,902	Re: Building an oscilloscope at home I'd pick a frequency between 20 and 30 kHz, then you can use a TV line output transformer core, and TV HT rectifier diodes will be fast enough. 10kHz risks making the thing irritatingly audible. Back in the 1960s I used to use a 50Hz iron 400-0-400 transformer driving a Cockroft-Walton multiplier (the circuit posted in number 72, above) to make -2kV for my VCR97 tube. The capacitors were 0.1uF and about 50mm diameter by 150mm long. I never thought of a high frequency oscillator. It would have made things a lot simpler, and I'd taken a lot of dead TVs apart for the components. I must have been stupid. All the clues were there. Cheers David __________________ Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done