The Sinclair QL Forum

I have the Minerva 1.97 and Toolkit II 2.20 ROM image if you want me to send it.

PM me your email and I can do that...

BP

Tonight I measured the voltages out of the official PSU on the 4 cables that are showing, as on mine the 6 pin DIN plug is missing! I got the following: Red - Green 16.2v AC Blue - White 9.9v AC SO my only assumption is that the label is not telling us the whole truth and the earlier wiring diagram ...

Did we get anywhere with the pinout for this?

15vac and 9v dc

Thanks

Russ

@Derek, You are correct and that is what has happened, 9v on the 5v line. I did not realise CST put the link in. JUst trying to ascertain what is damaged and what is not. So far 4 x DRAM and a 8049 destroyed, not checked the 8302 yet. Once I know they are all working then I will move onto the logic....

I am hoping that I may not have to change too much. My worry would be, if the board would be
better scrapped or rebuilt!

It was a shorting link put in by CST, by the main connector!

So far I have had to replace the 4 x DRAM and the 8049, just the ZX8302 to check and then
maybe some power can be applied.

Sorted.

Thank you.

OK! Just a cautionary tale. If using a QL motherboard from a Thor or unknown origin, check for this> https://preview.ibb.co/cxFQJw/IMG_2422.jpg ON my Thor board the regulators are removed and this link shorts the 7805 input to output. So if you want to use this board in a QL and then add the regulat...

Hi Derek, I have not got to the Thor cards yet. Still trying to get a stable system to test them with. I was trying to use the Minerva to test the QL mainboard removed from the Thor. Looks like the 5v line was up at whatever a normal QL PSU outputs at DC, 9volt plus! Not sure what will cope with tha...

Swapped the boards back. Put the regulators back on the board from Rich and cleaned up both boards. Rich's replacement board is now OK and running from the Sinclair PSU. Put the original Thor board back in and I get a black screen. Sooooooo back to diagnosing the issue with the Thor QL mainboard. St...