|Re: Hp-67 Card reader|
Message #6 Posted by Tony Duell on 29 May 2007, 4:30 a.m.,
in response to message #3 by Dan W
Do you have another 67, 97 or 41 (that is, something that can read a 67 card)? If so, try writing a card on the faulty machine and see if you can read it on the good one.
If you can't, check the head wiring, and check the head windings for continuity. There are 2 windings, IIRC, one has red and yellow wires, the other blue and orange wires (but I would have to check that in the schematics). If one winding is open, you can neither read nor write a card, and you're looking for a new head assembly (yes, I have had them fail).
The other thing to check are the decoupling capacitors on the various power lines. If one is defective, you get noise in the read amplifier from the motor. This will stop the machine from reading (although it will normally write OK).