The Sinclair QL Forum

Sooo, after much messing around I've fixed the problem. After much faffing around it came down to line 8 on J11 in the connector not being right enough. I looked at that damed connector so many times, but in the end I needed to insert a little paper behind the membrane going into the connector to ap...

Hi all I've been working on my QL to solve a keyboard problem I've been having. It was originally that no keys on the keyboard would register at all. Having tried two new membranes it was obvious the machine was at fault. I've messed around changing all sorts such as the 8049 and 8302 and I've final...

I agree Dave. While I hate to be beaten, I may need to look for another motherboard/QL :( and in the meantime get familiar with the schematic to see if I can work out enough of what should be happening to perform more checks. Going to need to up my kit with a simple logic analyser etc to see what is...

Based on the advice from the group I've checked the connectors and they are clear and tight fitting. I've also checked the continuity between the connectors and the 8049 and that is fine for all pins but still the same problem. I've checked the board for other solder or track breaks and can't see an...

Thanks for the info Rich. I've just plugged in a new 68008 and still the same. So that's a replace 68008, 8301 and 8049 and still not working, so time to check out the connectors based on your info

Cheers

Mike

Thanks Tobias, while I've re-seated the chips I've not checked the ports or expansion bus, so that's something else I can try

Did this particular issue get resolved? I have a QL in which I've tried two new membranes and I get no keyboard input at all. I've replaced the 8049 and 8302 and still get no keyboard input. The machine does give me the start F1/F2 start screen, so it would seem the CPU and ROM are OK. That said, th...