Hi all, Instead of jumping straight in and ordering an SLU, I decided to check the power supply voltages. My +12V rail appears to be only giving about +4.6V, where as the 5V rails are something like 4.9V, which should be fine.
This is an 11/23+ chassis and the power supply seems very large, but reasonably easy to trace. I thought I'd ask first if anyone has any tips on how to debug this, common components to fail or what might even result in this sort of voltage droop. Thanks! Aaron. Aaron Jackson via cctalk writes: > Hi all, > > I'm pretty new to PDP-11s. I recently got a PDP-11/73, M8192 CPU, two > M8067 RAM, M7195 (2 async SLU card with boot ROMs and an extra 128K of > RAM), plus a few other cards which I've removed to try and figure out > what is going on. > > While playing in ODT, the console completely stopped responding. I > hooked up pin 1 to a scope and I can see the UART clock, divide by time > per division and 16 and I get something close to 9600. > > The M8192 CPU has four diagnostic lights, as does the SLU. The CPU shows > 1000, which I believe is fine, and means it's in ODT. The SLU card has > 1111. I've had a Google and I believe this means it can't communicate > with the CPU. > > I've cleaned the contacts with 99%+ isoproyl, but no luck > unfortunately. Does anyone have any ideas? It was working and then it > wasn't :( > > Thanks, > > Aaron. -- Aaron Jackson PhD Student, Computer Vision Laboratory, Uni of Nottingham http://aaronsplace.co.uk