6128 Plus keys issue

[zeropolis79]

Dusted of my 6128 Plus to try out a new project only to find out the 3, X and C keys aren't working.


Could this be a membrane issue or one of the chips?


Many thanks..

[Bryce]

If it's only those three keys it's either a crack/break in the membrane or (more likely) dust and dirt on the membrane.

Bryce.

[Phantomz]

I had this happen to my 6128 plus, all I did was remove the membrane carefully and put it back together, I believe it happens because the two parts of the membrane got stuck together.

It's easy enough to do as the keyboard is only clipped together so you haven't got loads of small screws to unscrew like on some keyboards.

I'd give it a go if I was you.   

[zeropolis79]

Thanks - will give ti a try..

[zeropolis79]

Problem sorted thanks!

[zebulon158]

Another possibility for CPC Plus (in french) :
Réparation du clavier des CPC+ [Quasar Net] (cpcscene.net)

[Maniac]

I can confirm that removing the keyboard connector and reinserting it fixes the issue for a while and then it comes back again. I even managed to get another membrane when Trade In Post still had some in stock. This seemed to be a longer term fix but it too more recently has had the same issue. I've yet to be brave enough to remove the resistor network which I'd rather do properly than break it off as described in the article.

[CraigsBar]

I can confirm that removing the keyboard connector and reinserting it fixes the issue for a while and then it comes back again. I even managed to get another membrane when Trade In Post still had some in stock. This seemed to be a longer term fix but it too more recently has had the same issue. I've yet to be brave enough to remove the resistor network which I'd rather do properly than break it off as described in the article.

The problem will 100% be a build up of crud (Technical term) and corrosion on the springs in the keyboard connectors. Fortunately the 2 used in the plus are FAR more robust than those in the Spectrum 48k (which will collapse as soon as you breathe on them) so cleaning them is easy.


step 1: Douse the connectors with Isopropyl Alcohol
step 2: cut a piece of stiff cardboard (such as a Kellogs Cornflakes box - Other cereal boxes work too) into a strip that is about 3 inches long and the width of the connector
step 3. push the cardboard into the keyboard connector with unprinted side towards the contacts and wiggle it in and out a few times until the Isopropyl has all evaportated.
step 4: use the other end of the cardboard strip on the other connector
step 5: replug in the keyboard and re-assemble the plus machine
step 6: marvel at how well the keyboard works again and place that new membrane you bought on the shelf ready for when you *really* need it.


this simple cleaning trick has saved many a plus membrane for me. and I have not needed to unplug and replug a keyboard in years.


Hope it helps


Craig

[DanyPPC]

Thanks for the trick, I had same problem on my CPC+ series (464 and 6128), but even on standard classic 464 machine.

[CraigsBar]

Thanks for the trick, I had same problem on my CPC+ series (464 and 6128), but even on standard classic 464 machine.

I'll never have the issue on my CPC 464's, as they are both the tall key model