Amiga 500 Plus keyboard problems

[adgloride]

I recently bought a amiga 500 plus. I've had some problems with it so had to replace the disk drive and removed the battery. What I found out now I've got it working is some of the keys don't work. mostly on the left hand side of the keyboard W,S for example. I have got these keys to work but they only work sometimes. The return key does not work at all. I took out the keyboard membraine to have a look at it and it seems fine. Put it back in the amiga and still having problems. Can anyone help?

[D-Dan]

Make sure that the keyboard connector is firm and secure (A500 uses a wire connector, not a ribbon connector, IIRC - so no major task). It's about 15 years since I used an A500, but I did have a similar problem as best as I can remember, and that was the solution.

[adgloride]

Tried that still no luck. The keys that don't work are 3,e,d,c the space bar and the return key. 1 or 2 keys don't work on the numeric key pad either.

Either the connectors or the keyboard controller chip fails. Just try to find a replacement one, these failures are common for such old hardware.

[adgloride]

I think it may be easier just to replace the keyboard. I can get hold of an amiga 500 keyboard would this work on an amiga 500 plus?

[D-Dan]

I belive the A500 and the plus keyboards are the same. IIRC, the only significant difference between the two machines was OCS/ECS.

[Jope]

Originally Posted by D-Dan

I belive the A500 and the plus keyboards are the same. IIRC, the only significant difference between the two machines was OCS/ECS.

They're the same.

[Computolio]

The keyboard membrane might not be damaged on the key part, but on the part where it plugs into the circuit board. You should save the key caps and the circuit board for spare parts, they might come in handy in the future.

By the way-there isn't any way to repair a button membrane, is there? I could've sworn someone made a special pen or paint you could use to re-draw broken traces.

There are some paints but a friend of mine tried that on my A600 keyboard membrane with no luck. I didn't witness him doing that so I cannot detail more.

[adgloride]

Found the problem one of the metal prongs on the motherboard as snapped, what the keyboard connector connects to, the metal prong stuck is in the keyboard connector, and part of the metal prong is still in the motherboard. This is why I'm having problems with the keyboard. What I want to know is is it repairable? Or could I just replace the metal prong and how easy is it to replace? If the metal prongs come out easily (don't dare try it yet because I might damage the metal connectors all togeather) can I soilder the broken metal togeather and get the keyboard working again.

[Jope]

It is repairable, just get a similar pin strip, unsolder the old one and solder in the new one.. (logical, eh?) If your motherboard has a key pin (a missing pin) on the strip, you can pull that one out before soldering the new strip in.

The old one comes out easiest, if you first remove the old pins one by one. Grab a pin with a pair of pliers, then heat that pin from below and once the solder melts, pull it out.

Do that to the rest of the pins. Don't pull before the solder's heated all the way! You'll damage the motherboard if the solder isn't fully melted.

Then use a desoldering pump or solder sucking wick and clean out the holes.. Insert new pin strip, solder the pins on the bottom of the motherboard and let's rock.

Remember to remove the broken pin from the keyboard cable's connector before you plug it in.. ;-)

Oh, and no, don't try to solder the broken pin back together - it'll be like trying to band aid a snapped flagpole.. It won't hold.

[adgloride]

I got some pin strips from maplin to try and fix the keyboard on my miggy. The pin strips however seem slightly narrower and smaller than the orginal pins. I soldered them in and the pins seemed a bit loose. I now have to fix 3 pins because the broken bin was in the middle of the three pins at the right hand side of the pin strip. Now the power light won't come on and neither will the disk drive light but the miggy works, apart from the keyboard not working at all now. Will the pin strip I brought work or do I need another pin strip the same as the one already in the amiga. If I do need a new pin strip please could someone tell me where to buy one from.

[Jope]

Originally Posted by adgloride

The pin strips however seem slightly narrower and smaller than the orginal pins.Will the pin strip I brought work or do I need another pin strip the same as the one already in the amiga. If I do need a new pin strip please could someone tell me where to buy one from.

Hmm, you really should have bought one that has the same size pins and the same pin pitch.. There are a few standard sizes for this..

You might want to go to the electronics store with your keyboard, so you can verify the correct pin pitch with the keyboard's connector.

You probably can use your wrong pitch pin strip, but you'll need to break it apart and solder the pins to the Amiga individually.. Try and keep the plastic bits intact so it'll be easier to get the pins in the correct depth.. If you solder them too deep, they might short out on the RF shield under the motherboard.