How scarce (valuable) is core for the PDP-8?

--- Lawrence LeMay <lemay(a)cs.umn.edu> wrote: Someone else suggested: Charlie is indeed most wise, if you can read through his reams of detailed answers. I have always found him to be a great help in ferreting out bizarre tidbits of trivia. Having been to his house in Queens, I can say that he does have quite the wide range of hardware knowledge, but I think even he would blanch at attempting to disassemble a core pad and scavenge the bits (literally) to repair a broken plane. I know I'm intimidated by the prospect, but I figure worst case I broke something that was already broken. I wish I had one of the stereo inspection microscopes that I used when I worked on the factory floor at a Lucent plant in Columbus. It has a sliding base and an optional pneumatic pedal to fix the jig in place. We used it to inspect solder fillets on SMT edge connectors for circuit packs (the AT&T name for a PCB) for phone switches. If I had one of those for a month, I could probably get the view necessary to attempt to thread hair-fine wire through the cores. I do have a Weller temp-controlled iron to avoid scorching the PCBs and I do have a 1/64" tip for it (normally, I use a 1/32" tip for general SMT rework). The only hard problem I have is how to test the memory without assembling the entire plane first (due to the interconnections between the diode matrix boards and the individual core plane PCBs). Someday, when I have better tools and *lots* of free time... -ethan _________________________________________________________ Do You Yahoo!? Get your free @yahoo.com address at http://mail.yahoo.com