For those of you that want to mod a Northgate Omnikey 101 like this, and are annoyed with the original cable, here is another mod.
Personally, I am no fan of detachable cables anyway, and this one has several annoyances. It comes out at the right rear, with an L-shaped mini-DIN6 plug (which makes you think that a male-male PS/2 cable would work) pointing to the right, and an AT-style plug at the computer end, and it is coiled. My desk setup expects a cable going left, but I am just out of synch anyway.
But you can easily use a PS/2 cable from a junk keyboard, such as the $1 kind from the thrift store. I used a good long beige/gray IBM non-coiled cable that also had a ground wire. The original Northgate has a ground wire screwed to the metal case back, so I hooked it up that way anyway. Perhaps it is not really needed. I also pulled off the clip that the donor cable plugs into so that I could use female-female jumper connectors and avoid soldering, but that is only one way to do it.
Here is the pinout noted directly on a photo for your convenience. Always double-check on your own rig just to be sure.
The 2 blank wires do not seem to be doing anything, but I did notice one thing that seems strange. With the original cable running through an AT-to-PS/2 adapter, the arrow keys made the cursor fly, much faster than with my other keyboards. With this new wiring, the cursor moves very slowly, more slowly that with the others. I have not changed any settings, otherwise. Weird.
