Hey, so I'm getting squared away for my next build and once again I am using a donor amp as foundation. And once again all major complications will be related to the conversion part of the project. For my build the original schematic calls for a 320-0-320 HT secondary with a 430V B+. Just FYI The build calls for a solid state (bridge) rectifier, and a 3H choke is in series between B+1 and B+2. The power circuit can be modified as necessary, of course. In this case the donor (an Ampeg VT-40 that I picked up for $100) has the following power transformer: I annotated the voltages measured as indicated and according to the secondary wiring on the Ampeg schematic. - How am I going to get the 430VDC B+ (and current) I need out of this PT? - Can I use other combinations of secondary windings (red to CT, for example) to get closer to 320VAC? - Why do you think they separated the red HT and screen windings, does this indicate something about the PT current ratings? - Not having PT specs, is it possible to approximate the current ratings for each of the windings? - Can the power tubes plates really handle that much voltage (586VDC)??!? - Seems to be a lot of power circuit before the standby switch is tied back to the CT like a ground. Is that common? Looks odd to my inexperienced eye. - I was also wondering how that Screen power rail (E) got dropped so far, as it's after a full wave rectifier and I don't see any resistors in that circuit at all. I would expect the voltage to be much, much higher. Where all those volts go to? I have so many questions as usual. Thanks in advance.