Reading old HP-65 program cards

[Gene Dorr]

Does anyone have any experience or advice with respect to reading really old (ca. 1975) HP-65 program cards?

The National Air & Space Museum has in their collection the program cards that were used on the ASTP space flight in 1975, and I'm wondering whether there is actually any chance of being able to read them. It's doubtful they'd allow anyone to even try... but I'm just trying to determine if it's worth trying to convince them.

I understand the rollers degrade quite badly over the decades, so I wouldn't attempt with the HP-65 in their collection -- that would probably have a horrible outcome for both the calculator and the cards.

[Dave Britten]

(03-02-2021 06:37 PM)Gene Dorr Wrote:  Does anyone have any experience or advice with respect to reading really old (ca. 1975) HP-65 program cards?

The National Air & Space Museum has in their collection the program cards that were used on the ASTP space flight in 1975, and I'm wondering whether there is actually any chance of being able to read them. It's doubtful they'd allow anyone to even try... but I'm just trying to determine if it's worth trying to convince them.

I understand the rollers degrade quite badly over the decades, so I wouldn't attempt with the HP-65 in their collection -- that would probably have a horrible outcome for both the calculator and the cards.

I'd say you've got reasonably good odds, as long as they haven't been stored in any unusually harsh conditions. I have 5 of HP's application pacs for the 65, and have only found a few cards that needed to be rewritten. I also recently acquired a surveying pac for the 67/97 which included a couple of blanks that the previous owner had written programs on, and I was able to read those just fine.

Perhaps they could be convinced if shown a 65 that is reading cards without any issues?

[ThomasF]

Maybe a bit farfetched, but I remember from the old PPC times, that cards was examined by using magnetic powder. So, using a plastic film over the cards, some metal powder and the cards could be photographed and the pattern examined and decoded. Maybe there are other ways today to view magnetic patterns without touching the originals.
On the other hand, I think that it should be easy to find a restored 65 with a good cardreader and convince the museum that reading the card would be ok. I have recently restored a 65, and it could read cards that no one had touched for at least 35 years, without any problems.

Cheers,
Thomas

[Gene Dorr]

Re: visual decoding of the card -- I actually wondered about that for a while, as I too remember the discussion. In fact, there's a decent image of the magnetic recording on those cards on page 7 of the November 1976 HP Journal, in an article about the HP-67. But I am extremely skeptical that it could be decoded visually -- according to Bob Taggart, the density is around 300 bits per inch.

Plus, I don't recall anyone reporting (and documenting) the format of the data tracks recorded by the HP-65. I'd love to be wrong about that, though.

I have had issues reading old HP-71B magnetic cards, so I am concerned about even older HP-65 cards. They might be less of a problem though, since the HP-65 card reader was motorized, and so read/write speed would be less variable.

[teenix]

(03-02-2021 10:47 PM)Gene Dorr Wrote:  Re: visual decoding of the card -- I actually wondered about that for a while, as I too remember the discussion. In fact, there's a decent image of the magnetic recording on those cards on page 7 of the November 1976 HP Journal, in an article about the HP-67. But I am extremely skeptical that it could be decoded visually -- according to Bob Taggart, the density is around 300 bits per inch.

Plus, I don't recall anyone reporting (and documenting) the format of the data tracks recorded by the HP-65. I'd love to be wrong about that, though.

I have had issues reading old HP-71B magnetic cards, so I am concerned about even older HP-65 cards. They might be less of a problem though, since the HP-65 card reader was motorized, and so read/write speed would be less variable.

Some HP-65 card info here near end of document.

http://teenix.org/ClassicNotes.pdf

cheers

Tony

[Gene Dorr]

That's certainly helpful. It looks like there's no header at all, just the raw program memory. Any clue where I might find the decoding of the 6-bit values beyond what is shown in the example?

[Dave Frederickson]

(03-02-2021 10:47 PM)Gene Dorr Wrote:  I have had issues reading old HP-71B magnetic cards, so I am concerned about even older HP-65 cards. They might be less of a problem though, since the HP-65 card reader was motorized, and so read/write speed would be less variable.

But the 71/75 mag cards have a pre-recorded timing track so I think the data rate as recorded on the card would have minimal variation. This is why you never degauss a 71/75 mag card.

[Gene Dorr]

Right, I get that. But what I was thinking about was the length of time the write head has to induce flux on a given spot on the card would vary depending on pull speed. At any rate, my concern is with HP-65 cards, and anecdotal feedback from one person (so far) is that old cards still are readable.

Rollers: I no longer have my HP-65 (weeping and gnashing of teeth for my short-sighted stupidity), and so am unable to answer for myself the critical question -- do all HP-65/67 polyurethane feed rollers turn to gum over time, or are there environmental factors at work that cause some, but not all to degrade?

[teenix]

(03-02-2021 11:53 PM)Gene Dorr Wrote:  That's certainly helpful. It looks like there's no header at all, just the raw program memory. Any clue where I might find the decoding of the 6-bit values beyond what is shown in the example?

0 NOP
1 STO 4
2 3
3 2
4 1
5 STO 6
6 x
7 x!=y?
8 g
9 ROLUP
10 RCL
11 STO
12 f-1
13 ROLDN
14 f
15 RCL 8
16 RCL 7
17 X<>Y
18 6
19 5
20 4
21 RCL 6
22 +
23 RCL 4
24 E
25 x=y?
26 D
27 C
28 B
29 RCL 5
30 A
31 RCL 3
32 RCL 2
33 RCL 1
34 R/S
35 .
36 0
37 STO 7
38 /
39 A
40 B
41 x>y?
42 RTN
43 LBL
44 GTO
45 STO 5
46 DSP
47 STO 3
48 STO 2
49 STO 1
50 9
51 8
52 7
53 STO 8
54 -
55 x<=y?
56 CLx
57 Sub Pointer
58 EEX
59 CHS
60 LSTx
61 Pointer
62 ENTER
63 Top Of Memory

cheers

Tony

[Gene Dorr]

Awesome! Thanks Tony!

[rprosperi]

I've found that 95+% of the original HP-65 cards I've tried could be read. That includes both original HP-made 'clipped' cards that came with Pacs as well as user-written cards; I don't recall any specific bias to be worse for one group on the other.

Are the NASA cards the normal 'white' blank cards that HP sold, which NASA wrote programs on in the normal end-user way, or were they the special limited-run professionally made cards which HP would manufacture for large or significant corporate customers, in which case it's hard to say how well/if they are preserved, as not many of those made it out into the wild, and they may have been prepared in a special way.

[Paul Dale]

I've not had any trouble with the 65 cards I've got that were written back then. The card reader has been restored, otherwise they are pretty much guaranteed to be non-functional.

Getting the museum to let you try to read them but be a different matter but it's worth a try.

Make several backups of each card. I have had occasional issues with old cards not always writing properly and without turning the machine off and losing memory, you can't tell if they've worked or not (unless you have two 65s for the task).


Pauli

[Kostas Kritsilas]

After many years of disuse, I have, with the help of members here, been able to get my HP-65 up and running. The drive roller did in fact, turn to goo, and was replaced, and after some heroic efforts by members here, the read/write ability of the card reader was restored as well.

I have the original, what I would guess is the standard pack for the HP-65 with the factory original black, clipped cards. I am able to read all but 2 of the cards (10% failure rate). The two unreadable cards come up as read errors. The other cards do in fact read and operate correctly. I will eventually get around to re-keying in the two unreadable programs, but they are not something I need to use on a regular basis, so no big deal for me. These cards were all stored in the original, tranlucent plastic flip top box that came with the HP-65, so you had 10 cards stacked together and in one slot, with two slots full of pre-programmed cards, and two slots of blank cards, which is a different and denser format than the later HP-67 flip books used to store cards.

From that, you may have a data point on what kind of success you would have reading the HP-65 cards at the museum.

P.S. My HP-65 is a 1976 machine, as dated by the machine serial number (starts with 1604S). From what I know, the cards date from the same time.

[isanchez]

Hi,

The cards maybe dead or alive at the same time, as if I try to read them I can kill them, but if I do not try to read them I do not know if they are fine...(just joking, please, I do not want to open a debate! :-D

IMHO: I find the valuable issue is the registered code, not the cards. I have a couple of HP65 and they read 99% of the cards perfectly.

Regards

Ignacio

[Massimo Gnerucci]

(03-03-2021 09:36 AM)isanchez Wrote:  The cards maybe dead or alive at the same time, as if I try to read them I can kill them, but if I do not try to read them I do not know if they are fine...

The Schrödinger's card.

;)

[Didier Lachieze]

(03-03-2021 02:41 AM)rprosperi Wrote:  Are the NASA cards the normal 'white' blank cards that HP sold, which NASA wrote programs on in the normal end-user way, or were they the special limited-run professionally made cards which HP would manufacture for large or significant corporate customers, in which case it's hard to say how well/if they are preserved, as not many of those made it out into the wild, and they may have been prepared in a special way.

You can see the cards here. And the whole NASA HP-65 picture set here.

[rprosperi]

(03-03-2021 10:52 AM)Massimo Gnerucci Wrote:  

(03-03-2021 09:36 AM)isanchez Wrote:  The cards maybe dead or alive at the same time, as if I try to read them I can kill them, but if I do not try to read them I do not know if they are fine...

The Schrödinger's card.

Of course a very nice setup, but still, an excellent line! You must have smiled when you read that.

[rprosperi]

(03-03-2021 10:58 AM)Didier Lachieze Wrote:  You can see the cards here. And the whole NASA HP-65 picture set here.

Thanks Didier, I don't recall seeing these.

Looks like vanilla blank cards prepared in the normal way, with labels added using those small rub-on, dry-transfer letter kits. Although easy to apply, the rollers would rub-off some of the transfer ink and cause streaks, after repeated use. It appears these cards were never read.

Also note that "Mfg by" equates to "Sold to NASA by".

[Didier Lachieze]

Well, I think that the "Mfg by" applies only to the case, not to the HP-65...

[CY-CL]

This is really an interesting NASA HP-65 calculator. No connections plugs for the charger are present !!!!