Plessy core memory

I'm working on my pdp11/10 getting it back together. One problem I think I have is that the secondary memory (a Plessy 700101-100) may be shorting the -15 line for some reason. Working on it, but does anyone have a manual or anything like that for this kind of memory board? Alternately, what kind of Unibus 16k memory board exists to get a 11/10 requires +20 and -5, both of which are not provided by the power supply or sourced on a DD11-B backplane module. The 11/10 has +15, -15, and +5. On a related note, where did +20 come from for Unibus and which systems even supported it? Was it an 11/45,11/70 thing? Thoughts? C (Yes, I could build a regulator to take the 30 volts between +15 and -15 and create an independent 20 volts. Maybe. Likewise I could generate -5