|Re: HP41 Card Reader not Pulling Card|
Message #11 Posted by Colin Verrilli on 29 July 2012, 9:59 p.m.,
in response to message #7 by Luiz C. Vieira (Brazil)
Ok, well, it's working now!
Bad news Is I'm not exactly sure why.
Here's what I did:
I took the drive pin out and tried to insert a card. I noticed the motor was running for a short period of time.
I put the drive pin back in and inserted a card. The motor was now pulling a little, but not much and on the display I got "malfunction" and then "card".
Then I tried rotating the drive pin to different positions. No change.
I then used the ohmmeter to check the Card Insert switch continuity - between pins 4 & 5 of the top PC board. This time I noticed that the switch made continuity when the card first touched the contact but as I pushed the card further, continuity was broken.
I took off the top PC board and cleaned the contacts again. I also swapped the two metal strips around.
This time when I put it back together and tried it, the card was pulled through perfectly. I got a card error since it was a blank card, but then I tried to write a small program, clear it from memory and read it back and it worked!
I re-assembled the case, tried again and it still worked. That's all for tonight. Don't want to push my luck :)
Thanks everyone who responded for your help.
One more question. The two metal strips are supposed to be identical aren't they? Why would swapping them make a difference?