Hi,
After nearly two decades my 808 SET is finally operational, with an experimental PSU:
Due to the unusually high Z plate load (5k), I'd like to keep the B+ as close to the 450V rating of the caps as possible but without severe voltare overshoot during startup.
I'm currently using a 310V toroid, 1300V SS diodes and a simpe CLC filter which works quite well but my gut feeling tells me there's more output power to be harvested if the B+ is increased.
The best idea I can come up with using parts I already own would be a 360-0-360V AnTek toroid followed by a 430-440V Zener string and a big Mosfet as a pass device.
IDH tube rectifiers would solve the startup problem but the current draw is close to 300mA (almost 1/3 of that through the cathode follower driver stages).
Any advice for a current production Mosfet (or IGBT, or whatever) that would survive this situation in the long run?
After nearly two decades my 808 SET is finally operational, with an experimental PSU:
Due to the unusually high Z plate load (5k), I'd like to keep the B+ as close to the 450V rating of the caps as possible but without severe voltare overshoot during startup.
I'm currently using a 310V toroid, 1300V SS diodes and a simpe CLC filter which works quite well but my gut feeling tells me there's more output power to be harvested if the B+ is increased.
The best idea I can come up with using parts I already own would be a 360-0-360V AnTek toroid followed by a 430-440V Zener string and a big Mosfet as a pass device.
IDH tube rectifiers would solve the startup problem but the current draw is close to 300mA (almost 1/3 of that through the cathode follower driver stages).
Any advice for a current production Mosfet (or IGBT, or whatever) that would survive this situation in the long run?