PSU III Pre and Phono

[bob orbell]

Hi all, I have been correcting a Phono III for a chum after they drilled the board holes out to fit bigger components , New PCB put this right, he then got back to me about a lot of hum when using Phono and CD, so I have all three units here on the bench and for two days been scratching my head, with nothing connected to PSU the voltage took around 9 seconds to reach 370 volts, under load Pre was 209 volts and Phono was 211 volts, I chatted to Matthew questioning the resistor values as I don't have a PSU III circuit diagram, any chance of supplying me with one Greg, thanks, any how I think I have found the problem, the choke, I removed the choke and fitted a 510 ohm resistor across the pins on the board, voltage now rises almost instantly with too much at Pre and Phono. Has any one had a choke break down like this ? it measures just over 500 ohms. I there any better test to confirm good or bad. Thanks'. Bob