Some of the keyboard keys not responding (A1200)

[Kenan]

I took my keyboard apart and (thx Lord Aga for the advice!) cleaned the green membrane with 70% pure alcohol and reattached it. However, the same keys that didn't work before (arrow keys, HELP and "-" on the Numpad) are still unresponsive. The other keys work just fine. Not much of a big deal as very few games rely on arrow keys but I would still like to figure this out anyway. Could it be the cable ie. the part which plugs into the mainboard (at first I didn't think this might be the issue but now..)?

I haven't really looked into the keys as at the first glimpse, the contacts seem to be fine as well as the springs. So, hence my "Might it be the plug end of the cable" dillema..

[demolition]

It could very well be the end of the cable which slots into the connector on the motherboard which has a problem. Sometimes people pull out the cable without releasing the clip and this wears down the cable a lot, causing these connection problems.
I had the same problem with my A1200, and I just replaced it with another used keyboard.

I did read about someone who cut off the end and carefully peeled off the plastic to reveal some fresh tracks and made it work again, however it didn't seem that easy to perform.

[Kenan]

^^Thx for the reply. Not sure I'm gonna go that road (peeling off stuff) perhaps try to reattach it and see if it works. If not, well, I could leave it as it is or perhaps buy a new replacement keyboard.

[Mrs Beanbag]

Originally Posted by demolition

I did read about someone who cut off the end and carefully peeled off the plastic to reveal some fresh tracks and made it work again, however it didn't seem that easy to perform.

I did that once, it wasn't that difficult. There's a limit to how many times you can do that though, of course. I think I cut that one a bit short, it was a struggle to get it back in again but it did work.

[Kenan]

I took the cable out and when I reconnected it, now the keyboard is totally dead.
On the second cleanup and the second attempt, I managed to break that little white plastic thingie that gets plugged in with the cabel (round of aplause please! Thank you, thank you.. ).

So, untill I fix it or get a replacement keyboard or whatever, I guess, in the meantime, I'm gonna be enjoying my A600.

[jimbob]

About cutting the end of the ribbon. It is really simple, no peeling back or anything required. Peeling back the plastic beyond the carbon contacts is really difficult, the adhesive is likely to tear the trace off the other side. What has often happened is the contacts on the motherboard connector have been wearing the same spot for years and maybe reseated a few times and worn right through the carbon coating and the metal trace at the point of contact. If you hold it up to a light you can see the worn spots. All you need to do is slice off maybe 1mm at most with scissors or scalpel to move the contact point up to a fresh area. With luck and care you won't have to do it again for another 20 years.

Careful what you clean the membrane with too. I think the green plastic might be alcohol soluble. My cloth went very green the first time I did it, I just use water now.

How broken is the clip? If it's just the little retaining tabs it will still work, if you somehow snapped it in half, not so much.

[Kenan]

^^The clip attached to the motherboard is fine. I'm talking about the other part that goes with the cable. It's not "destroyed" but piece of it got disconnected so..

[demolition]

That clip was missing in the A1200 I got, and instead it had a piece of cardboard stuck behind the cable to keep it tight, but it's not a good solution IMO as it could put too much pressure on the cable so I found a cheap replacement clip from our well-known Amiga parts pusher on Ebay.
Cutting off 1mm sounds like a good and easy to do solution, I will probably try that with my non-working keyboard to see if that will get it working again.

[Kenan]

I spent a whole hour trying to make it work. I failed. No matter how hard I pushed the cable the keyboard was dead. Yes, I clipped the top and everything but no luck. The cabel is either bust or I'm doing something wrong..either way, gonna leave my 1200 in the cardboard box..untill I figure out what to do ..I'm too disheartend to buy a new keyboard as I'm not sure if it would work at all OR if I'm gonna attach it properly..perhaps I should simply consider getting one of those pc keyboards extension instead..meh..

[demolition]

The right way to connect the cable is to lift the clip, insert the cable as far as it will go and then push down the clip. Disconnecting is the reverse order and as with many other things, never use force.

[Kenan]

My clip is brokem (my fault), is there any way I can replace it with something else?
Also, is the cable folded on top while being inserted or is it straight, edges directly going in?

Thanks.

[Lord Aga]

Originally Posted by Kenan

On the second cleanup and the second attempt, I managed to break that little white plastic thingie that gets plugged in with the cabel (round of aplause please! Thank you, thank you.. ).

Oh man, I told you to use a screwdriver, not a piledriver

[demolition]

Originally Posted by Kenan

My clip is brokem (my fault), is there any way I can replace it with something else?
Also, is the cable folded on top while being inserted or is it straight, edges directly going in?

How broken is the clip? It might still be functional.
And I'm not sure what you mean with 'cable folded'? There is only one way the cable can go in as seen in this picture:

[Kenan]

Originally Posted by Lord Aga

Oh man, I told you to use a screwdriver, not a piledriver

Screwdriver, piledriver..potatoes, tomatoes..

Originally Posted by demolition

How broken is the clip? It might still be functional.
And I'm not sure what you mean with 'cable folded'? There is only one way the cable can go in as seen in this picture:

I was refering to when you plug the cable (the very top of the cable) if it should be slightly bent (the very top, the part that enteres the motherboard) or should it go straight as it is.

[roy bates]

if your not technicly minded just get a working keyboard there not that expensive.
or even just the membrane and just undu all the little screws from the backplate and replace the whole membrane.
if youve broken the plastic clip there dirt cheap on ebay,ive got a few spares but i dont know how much it would be to ship it.

[demolition]

It should just be straight. And then when the clip is pushed down, it presses the cable against the contacts in the socket.

[Kenan]

Tried, even fixed the clip which is now holding it down but no luck. Tried to plug it several times..Perhaps the cabel is simply dead.

[demolition]

Very likely. I found a working replacement keyboard locally for the equivalent of £10, so they are not expensive. If you get one with a different key layout, you can just move the keys from the old keyboard.

[Kenan]

Well, at least a valuable lesson has been learned (considering the clip usage). I'll be more careful next time.

Thanks guys for all your help and input regarding this matter.

[ElectroBlaster]

There is a solution!

Dead a1200 board - steal the clip from it. Highly unlikely as the board could well be harvested for parts

or

Find a dead/broken A500 keyboard, zero in on the controller board. If it has a single slot ribbon connector for the membrane, you can pilfer the plastic clamp as they are exactly the same type as the a1200 connector!