Mac Plus success - clean contacts!

All, another update on my Mac Plus - previously, I've had trouble with getting the +5V supply adjusted right, and noticed that reseating the power cable connectors helped. This time, I actually took some measurements. Looking from the solder pad on the far side of the power board, through the connector, the cable, and the connectors on the digital board, to the solder pad on the far side of that board, I saw anywhere from 1 to *5 Ohms* through that cable. No wonder it was not reliable! I'm astonished it ever ran long enough to get through the RAM checks! Pulled off both connectors, ran a VOM probe back and forth through each slot on both ends of the cable a few times. Got some 400-grit sandpaper and lightly sanded the pins on the board connectors, swabbed them off with Q-tips and isopropyl alcohol, then swabbed on a trace amount of silicone oil (in hopes that it'll be a while before I have to do this again). Resistance measurements, after reassembly, went down near enough 0 that I would not attempt to put a number on them other than << 0.2 Ohms. Pulled out all of the SIMMS, scrubbed their contacts with Q-tips and isopropyl, and re-installed. Reseated the CPU (Brainpower Accelerator daughterboard). Tuned the +5V supply back *down* a little, to about midway between where it would crowbar and where it wouldn't start (This looked on my ancient VOM to be around 4.95 V). System has been running solidly for several days now, through multiple power cycles and multiple extended play sessions. My 6-year-old is getting reacquainted with Dark Castle and Sim City. Hope this is useful; questions welcome! -- - Mark, 210-379-4635 ----------------------------------------------------------------------- Large Asteroids headed toward planets inhabited by beings that don't have technology adequate to stop them: Think of it as Evolution in Fast-Forward.