HP67 Card reader Message #1 Posted by Charles on 9 Feb 2004, 7:05 p.m.
Another one !
I also have a 67 which worked as a calculator but the card reader didn’t work at all. I changed the "gummy" wheel and it pulled the card through but didn’t read it. The action was a bit jerky so I took it apart again to check the clutch but 3 of the 4 red and black wires between the motor and bridge PCB became disconnected. Can anyone help with the order in which they should be reconnected ?
The two centre wires seem to be the black (one is still connected) while I think that the outer wires are the red ones. I’ve traced these back to the external power supply plugs. Looking at the calculator lying face down, one red wire comes from the left bottom round plug (this in turn is connected to the battery supply) while the other red wire comes from the right plug. Looking at the bridge PCB from the top (chip) side, which way do they go ?
Could the magnetic head also be faulty ? The clutch seems to be OK.
Thanks again for any help
Charles
(p.s. Perhaps I should give up trying to repair these !)
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