I have been given a link to the following site

http://www.homemade-circuits.com/2011/12/variable-0-to-300-volts-regulated-power.html?m=1

which has a regulator circuit for 0 - 300 VDC. Circuit is shown below. i am not clear on exactly how this circuit works and if it is any good.

i believe the 50 v zener is to protect the base of BF337 from over voltage
the 24v Zener is to protect the base of BF458

All the supply current and voltage is controlled by BF458 and the output voltage is controlled by the 1M ohm resistor. If the output voltage was to rise the resistor network will see this being across the output supply and so the voltage divider to the MOSFET gate will increase. This will then adjust the voltage through the MOSFET and cause the BF337 to conduct more which will then cause BF458 to adjust the output voltage to the original set voltage.

Have i got this correct and will this work
View attachment 94704

One of the magazines published a project for a HV PSU - it might have been Elektor.

The PCB service offered a board with alternative mounting holes so there was a choice to build it valve or solid state.

The FET type was unusual in being depletion mode so it behaved pretty much like a triode, it was most likely a MOSFET but I can't remember for certain.

 

Was this it, published 1961?

https://www.elektormagazine.com/magazine/elektor-200704/18496

I still have my collection of Elektor books, fantastic library....

 

That would be a good article to get hold off. This power supply would be a good addition to a lab

 

Was this it, published 1961?

https://www.elektormagazine.com/magazine/elektor-200704/18496

I still have my collection of Elektor books, fantastic library....

Much more recent than that - maybe 90s or later.

People were still playing with germanium transistors in the 60s.

 

That would be a good article to get hold off. This power supply would be a good addition to a lab

My real paper magazines are in a tea chest somewhere at the back of the garage.

 

I am tempted to subscribe to this online mag. I have been looking for a good one. i use to get the following

http://www.epemag.com/

this is cheaper but that HV supply you showed looks good

 

i used to get both from 1973 up to 2010, fantastic mags.....

 

i used to get both from 1973 up to 2010, fantastic mags.....

Elektor withdrew news stand distribution, so I wait for the whole year DVD in the spring.

 

Explanation impossibility quick and precise adjustment of the output voltage of the first circuit.
Kodensator 1 uF and 1 Meg resistors do not allow it to do.
That regulator does not have the drawbacks: