Northstar Horizon Update

Just wanted to share an experience. The Northstar that I got working this week up and quit working on me Thursday night. For no reason, it just stopped printing the NSDOS 5.1 banner on boot. I checked SINP on the bus and it was looping, I checked for read errors on the controller and found none. I swapped the 3 1488 line drivers around, then the 1489s for no reason and finally the 8251 USARTS to see if the problem would move from port to port. No dice. I checked for chips that may have popped out of sockets. I pulled chips and reinserted them. I pulled cards and reinserted them. Still nothing. I changed terminals. Nothing. Finally, it occured to me that I had flipped the chassis over to put some new rubber feet on the bottom and wondered if I could have shifted something, like a loose screw or nut. So I removed the motherboard and looked underneath. LO and BEHOLD! A previous owner had replaced an LS series chip and its socket and had not CUT OFF the excess leads on the bottom of the board!!! When I shifted the machine, it pushed the leads against the bottom of the chassis effectively grounding them! Once those were clipped and a piece of anti-static foam inserted beneath the motherboard, the machine now talks to the terminal FAR more reliably than before. So my Tip for the Day: When restoring a machine that isn't working, check out the user mods FIRST! They're the most likely suspect IMHO. Note: The machine still isn't acting 100% perfect. Sometimes it takes a reset or two to get it to boot properly. Is the N* A2 Ram-16 card known to be a bit flakey? I have an A3 that needs a capacitor replaced and I'm wondering if the A3 fixed specific problems with the A2. The problems it seems to be having look like memory problems to me. Thanks... Anthony Clifton