Recent content by JC8080

This is a Total Systems Mercury with the RAM expansion board. I have problems with it without the expansion board installed. Previously it was working fine, which is odd. The machine also works great with my Performer clone. That's odd you are having problems with your Performer clone, I have...

After more testing I think the problem is with the accelerator. I don't think there was ever a problem with the mouse button, I think the system was freezing right after booting to the desktop and the cursor was still able to move, but everything else was frozen.

I checked continuity from pin 7 of the DB9 connector to pin 13 on the VIA and it is good. One of the DB9 connector solder joints looked a bit dodgy (not pin 7) so I went ahead and re-flowed them all. The mouse button works now, though I have some other odd stuff going on that I'm sure is...

Thanks for the info and schematic, I'll get out the meter later and check.

Yes I should have been more clear, the pointer works properly, there is just no response when the button is clicked. I tried repeatedly clicking the button while I wiggled the mouse cable at both ends to check for an intermittent connection, the system never registered a click so I don't think...

I just set up my Plus and found that the system no longer recognizes the mouse button. I checked with a meter and confirmed the button is functioning properly. I recently had the machine apart and had the logic board out to install the diode needed to power the external SCSI port and found the...

I have a working board with the RAM expansion. If you decide to base something on this design and run into a roadblock where having access to a working board would help, and you are in the US, let me know and I would be willing to loan it out for nondestructive reverse engineering.

Plus accelerators are hard to find, and expensive when they do come up for sale. The MicroMac Performer clone will work with a Plus, though it is more complex than using it with an SE, because the Plus does not have an expansion slot. Here is a writeup I did on a Performer clone build, I talk...

Have you tried the Plus keyboard on the 128k? Do all the keys on the 128k behave the same? I have never had one of those mice apart, but I would start by putting some deoxit into the switch contacts and see if that fixes the mouse. Definitely don't start looking for replacements yet.

If you haven't already, look at btbs other post where he links to his redrawn schematics.

Great work. Those schematics look nice, maybe there is hope for my Classic II after all!

Thanks for the info, I'll add those to my cart for my next order.

The caps on the analog board (power board) on those machines tend to leak badly. Look at the PCB at the base of the capacitors, you will likely see a pool of liquid electrolyte. The caps on the analog board are all through-hole, so they are easy to replace with some basic soldering skills. The...

Here is a link to a thread describing a similar problem with the clones, I don't think a solution was found in the thread, but you might want to post on that thread and see if anyone has updates with their situations. Here's a post I did about my original presto board and which drivers I used...

Unfortunately I do not. What are the symptoms of your faulty board? There is currently a mostly complete HyperDrive kit on eBay, though $550 + $50 shipping is a good chunk of change.