organtechnology wrote:Is that what the 27V Allen power supplies were used for? I think the one I have came from an MOS-1 organ.
No, the Allen capture power supply went through at least three versions that I have seen. They would show a nominal 44V for the drawknob organs and 30V for tabs. However, I've had my hands on two drawknob consoles that actually ran closer to 50V and two tab-style organs that were over 45V. It's possible that the lower voltage was used on smaller organs?? --don't know, but the ones I had with two full rows of tabs didn't use 30V or anything close. Maybe their measurements were based on a 115VAC input where 120VAC is more normal in a residence.
I haven't had one of these power supplies fail yet though I did need to repair the first one I had which is why I had to dig into the circuitry more than I wanted. The 27V is from the main power supply that's usually on the right as you look at the back of the console. I think that was a nominal 24V for relays and such, but I'm just guessing as I never kept any of the Allen internals other than the capture supply. I don't have a spare at the moment and I imagine they are hard to come by across the pond.