Schematic for LR8 IRF840 variable PSU?

[GBeared]

Hi all. I wonder if anyone can please point me in the direction of a PSU schematic.

I am looking for a well designed variable PSU schematic using IRF840 MOSFETs and LR8 HV regulator. It will be used for powering small valve amp projects on the bench and so I would not need anything above 300V 200mA max. Something with current limiting/short circuit protection if at all possible.

Any suggestions would be greatly appreciated.
Thank you

 

[MarianB]

What is your input voltage range? And does it absolutely need to be with that mosfet or can it use something else?

 

[GBeared]

Hi, thanks for the reply.

Mains 240V but we are very close to a substation so actually more like 285VAC!
Does not have to be MOSFETs but I happen to have a bunch of IRF840 parts in a draw.

Thanks