The Sinclair QL Forum

I´d need some help with a broken Sandy Super Q Board Mouse.

At first sight, it didn´t look too bad: It´s an Issue 3 board with the mouse add-on as a piggy-back board:

However, when inserted into a QL, the computer doesn´t start any longer. Screen stays black.

I simplified the interface by removing the mouse add-on board, but no change.

I then removed the plastic cover and I could spot that someone did some de-soldering (between the resistors and the fat, black thong; hope you can see that): So the question is, what has been removed here and would that cause the computer to not boot? Anything else I can check?

Stefan,

here

http://www.dilwyn.me.uk/docs/hardware/index.html

are some re-engineered schematics (search for "QBoard" on that page)

Tobias

Hmm, mine does not had the mouse port piggy back instead it was on the main PCB.

I guess the different design has something to do with the fact mine has a RAM expansion as well.

Thanks for the suggestion, but I'm struggling with interpreting the text files. Beside from the ICs, I cannot really see anything about the small components I'm after. The PNG circuit diagrams, I don´t understand, I have to admit...

Hi,

I have a working SuperQ Board Mouse, without the ram expansion, I was going to add the Mouse circuit, but never got around to it.

The problem might be in the logic chips maybe a problem, you could test them with a logic probe.

I will post pictures of my board, but I think there are photos already on the forum.

Thanks Derek. Hmm, if that was the photo you were referring to http://theqlforum.com/viewtopic.php?f=2& ... use#p12060, then your Issue 3 board is totally different populated than mine in the left hand area. My board has additional resistors, capacitors and is missing the voltage regulator, but has this strange coil-thing instead. I´m totally confused now...

schombi wrote:I guess the different design has something to do with the fact mine has a RAM expansion as well.

As far as I know, sandy just produces SQB with mouse port + 512k, mine also had 512k.

Seems to be a different layout, as my mouse port was at the upper left part of the main PCB, nearby the shugart port (or parallel port, whatever is there).

schombi wrote:Thanks Derek. Hmm, if that was the photo you were referring to http://theqlforum.com/viewtopic.php?f=2& ... use#p12060, then your Issue 3 board is totally different populated than mine in the left hand area. My board has additional resistors, capacitors and is missing the voltage regulator, but has this strange coil-thing instead. I´m totally confused now...

I realize this thread is already pretty old, but the missing voltage regulator could mean that the board was maybe modified to run on a QL that has been changed to 5V. I mean, normally the expansion connector only provides 9V, so if there is no regulator it can't work and may even fry the chips. I'd remove the extra fluff and return it to the simple design shown in Derek's picture.

This board looks like it was modded to work in a Sandy QXT640 or another system that provided regulated 5V power.

The logic is likely history, given it was plugged into a regular QL.