Quote from: J M Fahey on November 27, 2015, 09:58:01 PM
The power amp is reasonable, but avoid the multiplier if you need any power, get HV from a proper HV winding.
Bias with a scope until you get rid of the crossover notch, we are talking very low current anyway, almost pure Class B
What about something like this smps with the MC34063 for the high voltage?
http://www.imajeenyus.com/electronics/20111010_40-400V_supply/index.shtml
And if I'm not wrong, you could use another chip to get -12v. I bet you could make it all run off a single 12v gel battery or a cheap laptop-type supply.
[EDIT]
I have run some simulations of a similar circuit on Proteus and I got to the following results, with the output adjusted for 280v with no load.
- 5K Ohms load: 280v, 56mA (15.68 Watts)
- 3K Ohms load: 247v, 82.5mA (20.37 Watts)
So, in theory, this could be a suitable power supply for small tube projects (probably up to 10w, depending on the tubes used).