A500 is donor to A4000 Keyboard

[iamaboringperson]

Hi,
Today I just transplanted the flat green floppy thing from my A500 keyboard to my A4000T keyboard! The A4000T keyboard was playing up(some of the keys weren't working) and both of these thin green things were the same model # so, I thought what they hey.

I havn't tested it yet, so when I do, I'll let you all know how it went! ;-)

[Kronos]

You replaced just the green foil ?

Should work, but I doubt wether it will fix your problems.

If you had/have dead key, you might want to replcace the black
plastic which carries the keys.

[Jope]

Edit: seems I didn't read everything.

Yeah, go for it. The contact foil usually isn't the culprit, but the elastomers under the key stems. You can swap them from the A500 keyboard or buy a PC Mitsumi keyboard and get them from there.

All you need to do with the foil is use a moist cloth and wipe off all the dust you can see. Then use TP or some other household tissue and dry it up very carefully so that it doesn't start oxidising (very very important, the metal bits are very thin and oxidisation eats through them very fast)

Also, my trick for revitalising the elastomers: crack open the keyboard, press down on an intermittent key to expose the elastomer, then just wipe the elastomer with a piece of office paper from your printer.. Mind the sharp paper edges, as they can cut the elastomers off.

A few wipes will leave some of the elastomer's hardened surface on the paper and expose the good bit underneath. Don't wear them down too much!

This works with most Mitsumi keyboards, be it Amiga, CBM 8-bit, or PC. :-)

[Lo]

I used to fix dead keys by replacing the conductive black rubber "feet" of A1K & A2K keys either by using C64 ones or less used keys on the faulty keyboard itself like F7,8,9.  The rubber feet crack and separate when the key is pressed resulting in no conduction.

[Jope]

The A1000 usually has a Cherry keyboard with keyswitches.. Are you sure you've seen a mitsumi one?

[Cass]

Brutality! Another A500 useless KB!
Take a look on the following URL, it must solve most of the problems:

http://www.qdev.de/?location=electronics/keyboardrepair

Afterall, we have over a 10 years keyboards on our amigas, we have to take care of them!
________
Bmw m47 history

[iamaboringperson]

Okay, I tried the keyboard last night, it worked except for the left 'alt' and left 'Amiga' keys. :-(

I inspected the black plastic part that holds the key conductor things this morning, and remembered that the green part was actually glued to it. While ripping it off I think I damaged some of the tracks, probably the ones that lead to the left alt and Amiga keys.

On the A4000 K/B the '9(', 'oO', 'lL', '.>' (a straight line down the keyboard), mostly didn't work, and the neumeric '2' key sometimes didn't work, and the '3' (newmeric KP) key never worked.

I've decided that even though it will take a while to get used to the new broken(and working) keys, I'll stick with the newer(A500) green thing.

I'm now just wondering what the best way to repair the tracks would be. I would rather not use solder, since it would probably melt through the green thing.

(Note about the A500: The A500 that was the donor, was my first Amiga, and I left it with my brother for a few years, and just like every other thing he owned, he didn't know how to look after it, so it's dead, the space bar was stuffed(the plastic hooks that hold the metal leavers were broken), so now it's spare parts)

[Dr_Righteous]

You can try using a conductive-ink marker.

[xeron]

I once transplanted the entire keyboard from an A500 to an A4000 keyboard case. The only thing from the A4000 keyboard (apart from the case) was the controller PCB. It worked fine for a year or so, but the A500 k/b was already on the way out when i swapped it (the 4K keyboard was worse, though, so it was still an improvement).

Now i've got a brand new one from Power Computing, and its lovely ;-)