May I ask what is the white scale on the magnetic card?

[angenieux]

I noticed that there are some "scales" on the pre recording program magnetic card of HP 67, and each scale is different. Do these scales have any special significance?

[rprosperi]

Those are merely 'boxes' into which you can write notes as reminders for what each button (in the top row) do. The earliest 65 cards had simplified but similar art.

[John Garza (3665)]

I think the poster is referring to prerecorded cards - they have what seems to be a code of tiny white boxes on the edge. Maybe this was a way of sorting them electronically during/after manufacture to help ensure the right cards ended up where they needed to be. But that's just a guess on my part.

-J

[rprosperi]

(04-12-2024 08:23 PM)John Garza (3665) Wrote:  I think the poster is referring to prerecorded cards - they have what seems to be a code of tiny white boxes on the edge. Maybe this was a way of sorting them electronically during/after manufacture to help ensure the right cards ended up where they needed to be. But that's just a guess on my part.

-J

Probably you're right, that he meant these. The question of the scales being used for measuring has come up many times, so this was the first thing that came into mind. There were questions in the past as to why these boxes were not a 'normal' size like 1cm or 1/4 inch, etc. I hadn't considered the white marks. Good correction.

[teenix]

The Standard Pac has a single white square, maybe a start marker, followed by the binary representation of the card represented as 2 x 4 bit binary coded decimal numbers. Maybe it was for machine sorting the cards into the storage envelopes.

So if * = a white square and . = space...

Code:


M01234567
SD-01A  
**.......
SD-02A
*.*......
SD-03A
***......
SD-09A
**..*....
SD-10A
*....*...
SD-11A
**...*...
SD-13A
***..*...
SD-15A
**.*.*...

cheers

Tony

[John Garza (3665)]

Back then, it was easier to read pips and construct a number than OCR the card labels !
Typically efficient for HP.

On the TI side, there were no pips on the SR-52 cards, and the 'label' cards (non-magnetic) of the TI-58/59 mere mass produced on one big sheet. Leaving the user punch out the individual cards.

-J