deskthority

First I bought a Focus FK-2002.
Not working.

Now I bought a Monterey K104.
Not. fucking. working.

Why?

What's broken? Not recognized as all?

Build an Aikon replacement controller

First, let's get a few generic troubleshooting questions out of the way:
Are you using an active PS/2-to-USB adapter? Passive adapters don't work.
Older keyboards draw more power and not all adapters are able to provide as much as some keyboards need. The adapter should also be connected directly to the computer and not through a hub.
If you connect the keyboard directly to the motherboard, you must do it when the computer is off. PS/2 and AT can not be hot-plugged or you would risk damaging the motherboard, the keyboard or both. Connecting through a USB adapter and hot-plugging that should work though.

Next:
One common fault in older hardware is that some electrolytic capacitor(s) has dried out. The IBM Model M2 is infamous for this but it is not alone. Open up and replace.

Not recognized at all.
I picked up Cherry boards that looked like they were used as ashtrays - all of them still worked fine.

I am using a 5pol-to-PS/2 adapter and am aware of the fact that PS/2 cannot be hot-plugged.

How can I recognize dried out electrolytic capacitors?

Opened the board up, it only has 2 capacitors, 1,34€ on ebay. Maybe worth a try

Bad coincidence. Listen to Findecanor.

Geroximo wrote: How can I recognize dried out electrolytic capacitors?

There are ways to check capacitors with a multimeter. Some have a capacitance-measuring mode. For those without it there are methods to check if it works or not. There are lots of guides of how to use them on the web...

Electrolytic capacitors tend to bulge or leak when they fail, but not all capacitors have this venting, nor does the lack of bulging/leaking indicate a perfectly functional capacitor. Go with what Finecanor says and use a multimeter to test the capacitance. Maybe the PS/2 adapter isn't supplying enough power to the older Alps keyboards?

Hey guys,
I changed all the capacitors on the boards and now they work!
The leds on the FK-2002 are dead but at least I can type on it now.
Thank you so much Findecanor! Much appreciated!

The M K 104 now only works, when you put it in XT mode, boot and then turn the switch to AT. If you boot it in AT the keyboard doesn't work. Well ... at least it works now when flippng the switch.

I'm glad to hear it!

Geroximo wrote: The M K 104 now only works, when you put it in XT mode, boot and then turn the switch to AT. If you boot it in AT the keyboard doesn't work. Well ... at least it works now when flippng the switch.

I had a problem somewhat similar to that on my Northgate. Turned out one of the capacitors had a bad solder joint. I had it replaced and that fixed it. See if your caps are all right.