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HP Forum Archive 04

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Ok, Repair Question Again - 41 Card Readers
Message #1 Posted by Mike Davis on 11 Oct 2000, 12:55 a.m.

I was quite successful in getting my 67 card reader working.

I then attempted to replace the drive wheel on my 41 card reader. Everything went smooth but after I got it back together, I get "Card Err" and "No Room" and sometimes "Malfunction", when I try to read cards. Most of the time it is "Card Err".

I cleaned the head before I assembled it and I double checked that the copper shim is in. Anyone have any know of something that I might have overlooked that can lead to this symptom.

The card go through the reader very smoothly but just can't be read. When I do a write, the reader prompts me for cards and does not give any errors. So, it looks like a read problem only.

There are no broken wires. Any ideas?


Re: Repair - Followup - Mechanical ?
Message #2 Posted by Mike Davis on 11 Oct 2000, 8:45 a.m.,
in response to message #1 by Mike Davis

In trying to figure out what might be wrong, I first am concentrating on some sort of mechanical thing. Two areas that I wonder about are the:

LED switch and the Mechanical switches.

First the mechanical switch. There are two switch contacts on the back of the card reader. Both of these switches appear to be activated as the card passes through the reader.

One switch is activated by the card striking a small tab on a rocker that stick out into the path of the card. As the card passes this rocker, it strikes the small tab and rotates the rocker which causes the switch to snap up and contact the circuit board. This appears to function ok.

The second switch contact is essentially the same design. But there is no tab and there does not appear to be anything missing or broken on the rocker. My confusion on this switch is that I don't see any way that this switch contact can be thrown. Nothing sticks out into the path of the card so this switch does not appear to be functional.

The only other thing that I can see that could go wrong mechanically, is the LED light beam (IR ?) switch. Not sure what the purpose of this is and if it is out, I wonder if that could be the source of the problem.

So here are my questions: 1) Are both of these switches functional in the 41? 2) I see only 2 switch contacts but there are 3 slots. Is this 3rd slot just unused with no switch contact? 3) What is the purpose of the LED?

If the reason that I cannot read cards is not mechanical, then I'll have to concentrate on the electrical side.

Re: Repair - Followup - Mechanical ?
Message #3 Posted by Andrés C. Rodríguez (Argentina) on 11 Oct 2000, 2:40 p.m.,
in response to message #2 by Mike Davis

Not 100% sure, but the second leaf switch may have to do with the detection of the corner (write protect) tab on the cards. The time interval between the detection of the card at the two switches will differ depending on the shape of the card corner. I think the LED detector senses the END of the card, so to stop the motor.

Re: Repair - Followup - Mechanical ?
Message #4 Posted by Mike Davis on 11 Oct 2000, 3:47 p.m.,
in response to message #3 by Andrés C. Rodríguez (Argentina)

As best as I can tell by watching from the end, as the card goes through, is that this switch detects when the card it removed.

The first one is actuated when the card is pressed in. As the card moves through the reader, the 2nd one is actuated.

It remains actuated, until the card is removed. As I physically remove the card, the switch is opened.

Re: Ok, I have the solution
Message #5 Posted by Mike Davis on 11 Oct 2000, 3:50 p.m.,
in response to message #1 by Mike Davis

Ok, for anyone else that runs into this problem, the problem was becaused the 2nd leaf spring was malformed, either by me or before I got the reader.

This copper strip is right over the heads and it presses the card against the head. The only thing now is knowing how much spring there should be.

I have the reader working now but a faint line is drawn on the front of the card when the card passes over this piece of copper. Don't remember if that is normal or not. Seems to me that a perfect adjustment should not put a line on the mag card.

Re: Yep, ok......
Message #6 Posted by Dave the "lostrabbit" on 12 Oct 2000, 5:24 p.m.,
in response to message #5 by Mike Davis

Hey Mike,

I told you to be careful with the leaf springs! Glad to see you got her going again, I'm out to check my mailbox for the postcard. You did send me one right? :)

Re: Yes and No...
Message #7 Posted by Mike Davis on 15 Oct 2000, 11:49 a.m.,
in response to message #6 by Dave the "lostrabbit"

Yes, I am sending a post card. No, I have not sent it yet. You'd be surprised at how hard they are to find in Renton.

I'm going to take a trip out to the airport later today to get one.

I also have not received the tube or O rings. However, I found both at a local hobby shop. I bought 3 feet of silicone 1/4" tubind for about $3 and got 4 very small O rings for about the same. I went with the tubing.

I will try and get the post card out today. It's just a matter of finding one, in a non-tourist area.

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