Denial

Hi all, I have a early Vic in very good condition apart from the pet style keyboard. it will only type characters on every other key on the two top rows of keys (qwertyuiop) but, the second rows of keys ( asdfghjkl) all work except for the return key. I'v tried a commodore 64 keyboard on the Vic and all is well, ruling out bad CIA chips. i'v had the keyboard apart and cleaned all the contacts (very carefully) with no detergents at all but still, it's exactly the same. any ideas what could be wrong with it?

Did you try mixing grafite into alcohol and dipping a q-tip into this. Then apply it to the pads

Is there a pattern to the non-working keys? Check the matrix shown in "VIC Revealed" it is probably one of the column or row lines. Either the pin on the connector is corroded or a wire has fractured.

Yes, there is a pattern of which keys work and which ones don't. As i said, i had the keyboard apart and the contacts where very clean with no dust or corrosion so it must be a problem with the block connector or a broken wire. what is the best way to clean the connector block that connects to the pins on the motherboard? i'v tried pulling & pushing it back on to try to create a clean connection but it didn't help.. i really like this PET keyboard & would love to get it working again as iv had this machine for 34 years & the C64 keyboard doesn't look or feel the same

If you have a multimeter then test the continuity between the connector block and the keyboard PCB. It might just be a dry joint on the PCB.

I had this problem briefly. I think it was with my PET keys VIC. It puzzled me ‘till I noticed that it only happened when I was using a SEGA joypad with option switches (auto fire, etc.). No other controller had this effect. I sold the offending controller. The problem never reoccurred.