jimp discovered his two C64 PSUs do not have all 7 pins in the plug, only the 4 required (9v AC, 9v AC, +5v, Gnd) and actually have the +5v pin in a different position to my PSU, TK's diagram of using a C64 PSU (http://www.ucapps.de/mbhp/mbhp_4xsid_c64_psu_optimized.pdf) and unfortunately the socket pin used on the MB-6582 Base PCB. As can be seen in these references:   http://www.hardwarebook.info/C64_Power_Supply   http://personalpages.tds.net/~rcarlsen/cbm/pinouts.txt Pin 5 is shown w