Phillipe, I am working on a project that will allow me to test many/most of my flip chips as you did. I got the idea from seeing what you did on your web site. I am hoping mine is not quite as bad off as the one you fixed. It was fully functional, and still partially is. My main problem right now is I have no memory access. I hope as have as much luck as you did. I like my 8i system, as it's what I originally learned on and finally got one of my own. Tim R --- On Wed 03/01, Philippe Sonnet < sonnet at sols.ucl.ac.be > wrote: From: Philippe Sonnet [mailto: sonnet at sols.ucl.ac.be] To: cctech at classiccmp.org Date: Wed, 1 Mar 2006 23:10:57 +0100 Subject: Re: My pdp-8i problem Dear Tim,It is very hard to answer your question. I also spent hours fixing my pdp-8/L, in which almost all circuits had to be repaired. It took me two years. The only way : use a logic probe and have a set a spare flipchips which you know are OK. I created a system to test the flipchips using a digital acquisition card on a PC (see www.sonnet.be). Collect all possible schematics, study them, have a confortable seat, stay calm and systematic and use a card extender to have better access to all the lines. Good luck,Philippe _______________________________________________ Join Excite! - http://www.excite.com The most personalized portal on the Web!