Search found 84 matches

by bagpuss22
Wed Nov 08, 2017 11:57 pm
Forum: Hardware
Topic: Anyone with a psu for Microperipherals Floppy Interface?
Replies: 45
Views: 8100

Re: Anyone with a psu for Microperipherals Floppy Interface?

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 ...
by bagpuss22
Thu Nov 02, 2017 11:22 pm
Forum: Hardware
Topic: Anyone with a psu for Microperipherals Floppy Interface?
Replies: 45
Views: 8100

Re: Anyone with a psu for Microperipherals Floppy Interface?

Did we get anywhere with the pinout for this?

15vac and 9v dc

Thanks

Russ
by bagpuss22
Wed Oct 11, 2017 12:29 am
Forum: General QL Chat
Topic: Bad evenings repairs
Replies: 10
Views: 711

Re: Bad evenings repairs

@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....
by bagpuss22
Wed Oct 11, 2017 12:19 am
Forum: Compatibles Corner
Topic: CST Thor 1
Replies: 75
Views: 9262

Re: CST Thor 1

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!

:?
by bagpuss22
Sun Oct 08, 2017 9:09 pm
Forum: Compatibles Corner
Topic: CST Thor 1
Replies: 75
Views: 9262

Re: CST Thor 1

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.
by bagpuss22
Sun Oct 08, 2017 9:07 pm
Forum: Wanted
Topic: Replacement ROM Image
Replies: 1
Views: 242

Re: Replacement ROM Image

Sorted.

Thank you.
by bagpuss22
Sun Oct 08, 2017 9:04 pm
Forum: General QL Chat
Topic: Bad evenings repairs
Replies: 10
Views: 711

Re: Bad evenings repairs

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...
by bagpuss22
Sat Oct 07, 2017 11:21 pm
Forum: General QL Chat
Topic: Bad evenings repairs
Replies: 10
Views: 711

Re: Bad evenings repairs

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...
by bagpuss22
Sat Oct 07, 2017 6:24 pm
Forum: General QL Chat
Topic: Bad evenings repairs
Replies: 10
Views: 711

Re: Bad evenings repairs

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...
by bagpuss22
Sat Oct 07, 2017 5:56 pm
Forum: General QL Chat
Topic: Bad evenings repairs
Replies: 10
Views: 711

Re: Bad evenings repairs

OK just found that the board that cooked my Minerva ROM somehow has a short around the 7805! I removed the 7805 and carrier and I still have 0 ohm between the in and out!? Anyone want to look at a Issue 5 circuit diagram and tell me what could cause this as I have been under a magnifying lamp to see...

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