Hi,
I am trying a KeyTronics KB5151 keyboard I just bought on eBay with a Racore XT keyboard adapter. The lights on the keyboard flash and there is no post error, but there is also no input once it boots to either BASIC or DOS. I just tried the keyboard on my PC 5150 with the same result. I opened up the keyboard and everything looks clean and unburnt.
Does anyone have any suggestions for troubleshooting steps I can try?
David
Problem with KB5151 keyboard
Re: Problem with KB5151 keyboard
Does yours have the rotting foam under the keys? You might not be getting input because the foam has deterioriated.
This keyboard works on capacitance. You'll see little foam discs with what looks like a Mylar backing. When those go bad the keys appear to be dead.
Mike
This keyboard works on capacitance. You'll see little foam discs with what looks like a Mylar backing. When those go bad the keys appear to be dead.
Mike
Re: Problem with KB5151 keyboard
I have that keyboard, and had to replace almost half of the foam pads on it. I just cut out foam squares and glued them in place. However, you should still be able to get a response from some of the keys though, unless all the foam pads are rotted away...
It's a huge and heavy keyboard, and IMHO kind of clashes with the small form factor of the Jr. I do use it on occasion for certain applications where easy access to the function keys and a numeric keypad are needed. Also typing on it is very mushy with little tactile feedback.
It's a huge and heavy keyboard, and IMHO kind of clashes with the small form factor of the Jr. I do use it on occasion for certain applications where easy access to the function keys and a numeric keypad are needed. Also typing on it is very mushy with little tactile feedback.
Re: Problem with KB5151 keyboard
Well, I was surprised by just how big and heavy this keyboard is. Anyways, I cannot get any of the keys to register a keystroke. In case I did not mention it, the LEDs give an initial flash on power-up and it passes the bootup keyboard test with no errors. In the PC BIOS POST there appears to be code that checks for a specific character string from the keyboard and it must be getting that for it not to indicate an error. This leads me to believe it is not an error between the keyboard controller and the computer, but between the key matrix and the controller inside the keyboard. When I was cleaning the insides I did not see any debris that would have come from disintegrating foam pads. With only a multimeter I can only check that all the chips are getting 5 volts. My hopes for a simple fix is vanishing.
Re: Problem with KB5151 keyboard
Took it apart again and the little foamies are all rotted. I blew a little air it that direction and a bunch of mylar disks and foam dust came out; strange that there was none already falling out. Anyways, I should be able to trigger a response from the keyboard by manually touching the discs onto the sensor pads, but it still doesn't work.