Help me restore this Focus FK-2001

[Geroximo]

Hey,
I'm having this sweet little Focus FK-2001 (german version aka FK-2002) right in front of me. I think it has complicated white ALPS, but im unsure.


There's just one little problem. It doesn't work 
When it's plugged in, all LEDs (CapsLock, NumLock and ScrollLock) are on permanently and it does not register anything.

I'm going to open it up and take a look inside. Does anybody know what the problem with this thing could be?

edit: I'll give the switches a good clean and lube them if I can get it running again

[Daniel Beardsmore]

Does the logo lift up to reveal DIP switches? It might still be old enough to be XT/AT switchable, and Focus hid the DIP switches under the badge.

Incidentally, those switches … fascinating. Unbranded scrawly switches. I've never seen that variant before — the scrawly switches I've seen have always been branded. What's the date code on the controller chip?

(There are a number of strange variants of white Alps switches that I assume came from factories outside of Japan.)

[Touch_It]

A shot in the dark, but maybe it has a bad capacitor somewhere?  I know nothing about this keyboard in particular, but just an educated guess based on the symptoms.  Also, does this have a ps/2 end on it, and are you using an adapter?  Could be the culprit here as well.

[Geroximo]

Controller Chip:


Date in the housing 10/1990

It also has an AT/XT switch, set on AT. I'm using a 5-pol DIN to PS/2 adapter.


I cannot see any obvious damage on connectors or resistors. Maybe reheating the soldering points helps?

NOTE: LEDs are off initially, but lighten up as soon as you press a key.

[Nover]

http://circuit-board.de/forum/index.php/Thread/15776-Mechanische-Tastatur-reparieren/

Quite sure that's the one you bought on ebay one or two weeks ago. Maybe it helps to see what kinda attempts have already been made. It's one nice keyboard, so GL!

[Daniel Beardsmore]

You're connecting it to your PC via PS/2 with the PC switched off, or are you using a PS/2 to USB converter? If the latter, which one?

[Geroximo]

http://circuit-board.de/forum/index.php/Thread/15776-Mechanische-Tastatur-reparieren/
Quite sure that's the one you bought on ebay one or two weeks ago. Maybe it helps to see what kinda attempts have already been made. It's one nice keyboard, so GL!

it is.

You're connecting it to your PC via PS/2 with the PC switched off, or are you using a PS/2 to USB converter? If the latter, which one?

via PS/2 with the PC switched off.

[Snowdog993]

Did you clean the contacts between the controller and the keyboard?  You are saying it is lighting up.  Maybe that's it.

[Daniel Beardsmore]

Hm, unless the cable's damaged, it's starting to look like component failure on the PCB.

[Geroximo]

Update:
I'm planning to use the switches on a custom board.
Thx for your input.