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Alexanderpentagon · (This post was last modified: 08-17-2023 10:38 AM by Alexanderpentagon.)

Hi, A couple of year ago I bought an HP-97S that missed the BCD pod. I restored it partially , I changed printer gear etc. then I started to search an eBay another 97S also in bad condition but with the pod in order to make a complete calculator. After two years of searching I found this from US eBay: one 97....without S but with original .. 'primitive' ... Pod. The date-code of this strange 97S is 1708A00949, the label and the board are the first version of 97 ( without the IDC header) . The pod cable end was soldered and deployed in professional style ... seems to be made in factory.... ( like MIL-std object) The chips date code are compatible with the first series of 97 and prior the launch of 97S . The housing of cable exit in the shell of calculator is made in factory , surely not hand-made. The surprise was when I opened the pod! It was a totally different pcb layout of the photos that are on the web ... an earlier release ...datecode on the chips and correction wires confirm that . Do You have information on 'earlier' 97S , images and datecode?
Thank You in advance
KR
Alex
p.s. I'm trying to include imgs

Alexanderpentagon · 08-17-2023, 01:13 PM

other images

brouhaha · 08-17-2023, 05:12 PM

I've seen several HP-97S units made as you describe from the early 97 PCB. I think that was how they built early 97S units, before the PCB redesign.

Kostas Kritsilas · 08-19-2023, 07:27 AM

I had one of these "non S" HP 97S a long time ago. At the time, I did some research, and found that there were standard HP-97 units that were modified by a third party to add the external pods. They were some form of a non-standard pod that communicated using some handshake and BCD encoding. That was as far as I ever got. Since this was a while ago, I can't recall the name of the company that did this, altough later on, HP brought out the HP-97S and the company stopped making there own version of the HP-97S. Evidently, there was enough demand that HP felt that they needed a HP-97S.

Alexanderpentagon · 08-19-2023, 08:56 AM

(08-19-2023 07:27 AM)Kostas Kritsilas Wrote: I had one of these "non S" HP 97S a long time ago. At the time, I did some research, and found that there were standard HP-97 units that were modified by a third party to add the external pods. They were some form of a non-standard pod that communicated using some handshake and BCD encoding. That was as far as I ever got. Since this was a while ago, I can't recall the name of the company that did this, altough later on, HP brought out the HP-97S and the company stopped making there own version of the HP-97S. Evidently, there was enough demand that HP felt that they needed a HP-97S.

Ok , but , from the images I can see that my pod is an original HP Pod and the printed circuit boards are original HP with early/pre-production chips and design ( as I can see on other photos in the web)... I appreciate if You can post any link or photos related
Thank You
KR
Alex

TellyS · 08-19-2023, 03:27 PM

I have an HP 97S that i think is an original. It was not working, so I replaced all ICs (with the exception of the one that was HP custom ROM) and the calculator worked great. I have attached some before/after pictures, if they help. These are from the top board. I don't remember why I did not take any pictures of the second board. Maybe a left that one alone.

Anyway, included for reference. And I also have the replacement IC list, if ever needed.

Kostas Kritsilas · (This post was last modified: 08-23-2023 07:43 AM by Kostas Kritsilas.)

(08-19-2023 08:56 AM)Alexanderpentagon Wrote:
(08-19-2023 07:27 AM)Kostas Kritsilas Wrote: I had one of these "non S" HP 97S a long time ago. At the time, I did some research, and found that there were standard HP-97 units that were modified by a third party to add the external pods. They were some form of a non-standard pod that communicated using some handshake and BCD encoding. That was as far as I ever got. Since this was a while ago, I can't recall the name of the company that did this, altough later on, HP brought out the HP-97S and the company stopped making there own version of the HP-97S. Evidently, there was enough demand that HP felt that they needed a HP-97S.

Ok , but , from the images I can see that my pod is an original HP Pod and the printed circuit boards are original HP with early/pre-production chips and design ( as I can see on other photos in the web)... I appreciate if You can post any link or photos related
Thank You
KR
Alex

Alex, as I wrote previously, I HAD that HP-97 with the ribbon cables, as in no longer have anymore. So pictures are not possible.

From recollection, the printed circuit boards inside the machine were all HP original. There were soldered wires all over the motherboard, a stuck (as in foam tape/double sided tape) clamp used as a strain relief, and two ribbon cables coming out to DIP connectors. The DIP connectors were NOT marked HP. The ribbon cables exited the back of the case, in the small recess that joins the top to the bottom case halves. There were two square cut rectangular cut outs to allow the cables to pass through.

Alexanderpentagon · 08-23-2023, 08:05 AM

(08-19-2023 03:27 PM)TellyS Wrote: I have an HP 97S that i think is an original. It was not working, so I replaced all ICs (with the exception of the one that was HP custom ROM) and the calculator worked great. I have attached some before/after pictures, if they help. These are from the top board. I don't remember why I did not take any pictures of the second board. Maybe a left that one alone.

Anyway, included for reference. And I also have the replacement IC list, if ever needed.

From Your photos I can see You have a release B of PCB , I Have a A2 reiease... so it's compatible with my 'proto' /pre-series theory.
Thank You

Alexanderpentagon · 08-23-2023, 08:11 AM

(08-23-2023 07:42 AM)Kostas Kritsilas Wrote:
(08-19-2023 08:56 AM)Alexanderpentagon Wrote: Ok , but , from the images I can see that my pod is an original HP Pod and the printed circuit boards are original HP with early/pre-production chips and design ( as I can see on other photos in the web)... I appreciate if You can post any link or photos related
Thank You
KR
Alex

Alex, as I wrote previously, I HAD that HP-97 with the ribbon cables, as in no longer have anymore. So pictures are not possible.

From recollection, the printed circuit boards inside the machine were all HP original. There were soldered wires all over the motherboard, a stuck (as in foam tape/double sided tape) clamp used as a strain relief, and two ribbon cables coming out to DIP connectors. The DIP connectors were NOT marked HP. The ribbon cables exited the back of the case, in the small recess that joins the top to the bottom case halves. There were two square cut rectangular cut outs to allow the cables to pass through.

Ok , Thank You for the info Smile