"New" PDP-8

--- Loboyko Steve <sloboyko(a)yahoo.com> wrote: What else would be "useful" from a DECmate board? I agree about the difficulty of removing chips from multi-layer boards. Depending on the exact nature of the power/ground pins/planes, it can take a lot of heat to remove the chips. Usually, you pick either the chip or the board as what you want to survive and you sacrifice one for the other (it's possible to do both, but it's a *lot* more work, and sometimes you still ruin one or the other or both). I recently pulled a custom 20-pin DEC chip from a DWBUA to install in another DWBUA in an attempt to get one working board. First, I had to remove the dead chip from the recipient board - that took 30 minutes to get the power/ground pins out and the thru-holes clean; then I had to remove the chip from the other board without destroying the chip - another 30 minutes. It's easier with the "right" tools... all I had was a Weller temp-controlled soldering station, solder, solder wick and a solder sucker. With about a $500 desoldering station, it probably would have taken under 10 minutes. But, again, I'm curious what you would save from the DM board if you could. Personally, if I ever build Bob's design, I'll probably crack open a DM (I have one I, one II and one III) and borrow the CPU chip. EPROMs I have aplenty, as well as PALs, GALs and TTL "popcorn" parts. I can't imagine what I'd want to pull from the donor system except for the CPU chip itself. That way, I could put it back anytime I wished. -ethan __________________________________________________ Do You Yahoo!? Yahoo! Greetings - send holiday greetings for Easter, Passover http://greetings.yahoo.com/