Slipping magnetic cards

[AndiGer]

I have here some cards - also the diagnostic programs SD-15A and SD-15C from orignal Standard Pac - that run thru the card reader of more than one calc Hp-67 and HP-97 smoothly but at the end of the card slip thru the reader causing Error. Some read one side ok the other side slips. Other cards read well both sides.
Is there a recommended treatment to make the cards read well again?
I remember for TI cards ... spit on them ...

[rprosperi]

(11-19-2017 09:25 PM)AndiGer Wrote:  I have here some cards - also the diagnostic programs SD-15A and SD-15C from orignal Standard Pac - that run thru the card reader of more than one calc Hp-67 and HP-97 smoothly but at the end of the card slip thru the reader causing Error. Some read one side ok the other side slips. Other cards read well both sides.
Is there a recommended treatment to make the cards read well again?
I remember for TI cards ... spit on them ...

Here is one solution:

http://www.hpmuseum.org/cgi-sys/cgiwrap/hpmuseum/articles.cgi?read=63

[AndiGer]

Dear Bob,

Thank you for your reply. That post I already had found (and practised but a little modified using paper that is as thick as the card).
My actual problem is that the cards (have several with the problem) run thru smoothly but when the card is nearly thru the motor accelates for a short time before it stops and card is thru - but resulting in an "Error" display.
Sounds as if the card slips a very small way. Other cards don't behave like this but the faulty card(s) in another reader behaves the same. So I know it should be a card problem. Seems like the card is slippery somehow. Already did some cleaning on the upper side of the cards using some alcohol.
Don't believe re-writing the card will solve the problem.

[PANAMATIK]

(11-20-2017 08:58 AM)AndiGer Wrote:  Don't believe re-writing the card will solve the problem.

Did you find blank cards with the same problem? If the surface of some cards is slippery it could be happen also to blank cards. If so, you can easily check whether rewriting solves the problem, before rewriting the original cards.

Bernhard

[Sylvain Cote]

My trick for slippery or oxidized magnetic cards is to rub them with a white gum pencil eraser from staedtler.
It worked most of the time on all magnetic card types, the short ones (65/67/97/41) and long ones (71/75).
You must hold them very hard on the extremities when you apply the gum, because if you do not, the card will follow and bend. When that happen it is over for that card.
To solve the issue I have made myself a card cleaning jig using a stainless steel ruler (cut at the appropriate length) and strong paper clip to hold the card on each end.
Sylvain
edit: typos

[AndiGer]

Thanks for the advices. Also the pencil rubber didn't change the behaviour.
Came to the idea to try in the HP-41 card reader. After I got checksum error there I decised to add the clipped corners and rewrite the cards. That finally did the job :-)
Somehow the 97/67 readers seem to have also some logic when to stop the motor running depending on the card read successfully?
After writing the before malfunctioning card with motor acceleration it now works like a charm.
Andi

[rprosperi]

So you were able to write the 67/97 Diagnostic card program back to the original 67 card, using the clipped corner technique, with a 41 card reader?

I would have thought writing that after 'translating' the card to '41 FOCAL would not work in a 67/97 again. I guess the diag card uses only very simple instructions that are not changed during the translation process.

Thanks for sharing this news.

[AndiGer]

Dear Bob,
No, sorry for the confusion I may have caused.
The HP-41 was only to verify the cards are good or not.
I rewrote it in my HP-67. And read it there, in my HP-97 and in the HP-41 card reader.
Andi

[rprosperi]

OK, thanks for clarifying. I was surprised by my wrong interpretation, so this sets things back to what I would expect.

[knife31]

I have had some luck by trying to read the card in a different calculator such as the HP41/67 or 97. Worked for a couple but not all.
Randy

[John Garza (3665)]

You could try...

1) clean the mag head and card surface
2) clean/polish the battery contacts
3) adjust the drive roller to apply a bit more pressure on the card
3) if it is in fact damaged data and the card surface is still good, the Kemper correction card is the preferred method for recording onto write-protected cards.

-J