Problem with trackball of 'new' M5-1

[Campus]

Hi,

I bought a 'new' IBM Model M5-1 and cannot get the trackball to work. I tried two different active PS/2-USB converter but both failed. The keyboard always works fine, the trackball never works. I disassembled the keyboard and hooked an oscilloscope to the data and clock line of the connector of the main pcb but I was unable to see any rectangular signal that I would expect on a PS/2 line.

As I am now out of ideas I would really appreciate if someone would have an idea how to proceed in such a case.

Thanks!

[Computer-Lab in Basement]

I can't attest to the M5-1 from personal experience, but I can say that I had issues with the M5-2.

If you can, I'd try using just the trackball on a dedicated PS/2 port of a PC with a PS/2 port on the motherboard, see if that makes any difference. In my experience I was able to get the trackball working after several PC reboots on a dedicated PS/2 port.

Alternatively, maybe the SDL cable is defective on the mouse side of things; not sure where you'd obtain a replacement though; maybe Unicomp or ClickyKeyboards?