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John Garza (3665) · 08-01-2023, 06:18 PM

I am in a pickle.

I have 2 broken machines a 25C and a 29C.
But only enough parts to repair one of them!

Let's take a vote. Which one do you think I should repair?

Of course the 29C is more powerful, but the 25C is more historic and groundbreaking.

-J

Massimo Gnerucci · 08-01-2023, 06:29 PM

29C, there are many 25C out there.

**rprosperi** · 08-01-2023, 06:32 PM

(08-01-2023 06:29 PM)Massimo Gnerucci Wrote: 29C, there are many 25C out there.

1 +

Josef · 08-01-2023, 06:35 PM

I also vote for the HP-29C, they are rarer and significantly more expensive

Maximilian Hohmann · (This post was last modified: 08-01-2023 07:13 PM by Maximilian Hohmann.)

29

or: repair the 29 and put a Panamatik board into the 25.

agarza · 08-01-2023, 10:35 PM

I agree, HP29C is the one to fix.

Johnboy · 08-01-2023, 10:59 PM

Repair the 29C then give it to me !!!!

BobVA · 08-02-2023, 02:35 AM

+1 for repairing the 29C. If the 25 has enough surviving parts also +1 for repairing it with either a New ACT or, better yet, an LP kit from Panamatik.

John Garza (3665) · 08-02-2023, 03:41 PM

Wow! 7-0 in favor of the 29C. So be it.

The details:

25C is functional except for a bad '5' key. My fault as years ago (1990's) I was over aggressive in cleaning and punched a hole in the metal strip. New metal should fix it.

29C cannot reliably store/recall numbers in the primary registers. Manual indicates this is likely a faulty DS0 chip - the same type as in a 25C.

I do have an uninstalled spare Panamatik package I could use on the 25C once I remove the memory chip. GPS and printer too!

-J

Massimo Gnerucci · 08-02-2023, 03:43 PM

A Win-Win situation, then.

John Garza (3665) · 08-02-2023, 04:20 PM

When I bought the Panamatik, it did not have an upgrade to use subroutines in the 25C.
Does anyone know if they ever did that?

I'd gladly trade some of the less desirable features (temp, stopwatch, anti-flicker, right-adjust, etc.) for subroutines.

-J

**rprosperi** · 08-02-2023, 07:40 PM

(08-02-2023 04:20 PM)John Garza (3665) Wrote: When I bought the Panamatik, it did not have an upgrade to use subroutines in the 25C.
Does anyone know if they ever did that?

I'd gladly trade some of the less desirable features (temp, stopwatch, anti-flicker, right-adjust, etc.) for subroutines.

-J

The HP-25A ACT behaves exactly like the original 25C, so constant memory but no subroutines.

The Enhanced Act (which it sounds like the one you have) and Woodstock Low Power (WLP) do not really support HP-25 subroutines per se, since the 25 doesn't, however the personality of a machine with either of these boards installed can be set to be a complete 21, 22, 25, 27, 29, 31, 32, 33, 34 or 67, with all the features of that model (Enhanced Act does not do 31, 32 or 33), all with Constant memory, etc. Of course overlays must be installed if you plan to use it long-term as one of these others as the KBD is different on all models.

Sanjeev Visvanatha · 08-03-2023, 01:42 AM

A working 29C and a 25E are good problems to have!

For the Continuous aspect of the 25E - does it behave exactly like the 25C? As far as I know, the 25C retains the 49-step program memory, 8 addressable storage registers, and LAST X register. Whereas, the 25E will always retain the program memory, but to store also the 8 registers, LAST X, and stack, you need to slide the run-prgm switch in order to force a write to flash. Is that correct?

Paul Dale · 08-03-2023, 02:09 AM

Don't even think about it: 29C always.

Pauli

John Garza (3665) · 08-03-2023, 02:20 PM

(08-03-2023 01:42 AM)Sanjeev Visvanatha Wrote: you need to slide the run-prgm switch in order to force a write to flash. Is that correct?

Yes, that's my understanding. That also means you have a limited number of write cycles to flash ram. Around 100K I think. Still, probably more than I will ever use.

I wonder if it has the option to use the existing ram chip. I didn't see that in the manual.
Anyway, not applicable to my situation as that ram chip will be donated to the 29C

Tonight I should finish the transplant. Last night I unsoldered the ram chip from the 29C and installed a low profile socket. The Hakko FR-301 breezed right through the unsoldering job.

-John

**rprosperi** · 08-03-2023, 02:38 PM

(08-03-2023 01:42 AM)Sanjeev Visvanatha Wrote: For the Continuous aspect of the 25E - does it behave exactly like the 25C? As far as I know, the 25C retains the 49-step program memory, 8 addressable storage registers, and LAST X register. Whereas, the 25E will always retain the program memory, but to store also the 8 registers, LAST X, and stack, you need to slide the run-prgm switch in order to force a write to flash. Is that correct?

No, it's complete RAM retention. including stack, Last-X, program memory. Enter numbers into stack, power-off, power-on, stack is back to how you expected, program runs, etc. So, strictly speaking not fully compatible, but in a very nice and useful way! Smile

Sanjeev Visvanatha · (This post was last modified: 08-03-2023 06:23 PM by Sanjeev Visvanatha.)

(08-03-2023 02:38 PM)rprosperi Wrote: No, it's complete RAM retention. including stack, Last-X, program memory. Enter numbers into stack, power-off, power-on, stack is back to how you expected, program runs, etc. So, strictly speaking not fully compatible, but in a very nice and useful way!

Hmmm. I just purchased my first Panamtik ACT, and that is not the behaviour I see. R1.18 of the ACT behaves as I described above.

**rprosperi** · 08-03-2023, 06:48 PM

(08-03-2023 04:55 PM)Sanjeev Visvanatha Wrote:
(08-03-2023 02:38 PM)rprosperi Wrote: No, it's complete RAM retention. including stack, Last-X, program memory. Enter numbers into stack, power-off, power-on, stack is back to how you expected, program runs, etc. So, strictly speaking not fully compatible, but in a very nice and useful way!

Hmmm. I just purchased my first Panamtik ACT, and that is not the behaviour I see. R1.18 of the ACT behaves as I described above.

This may be a difference between the different versions of PANAMATIK's ACT modules. I have the WLP, and should have noted that in my post. Which version do you have? If the Extended ACT, I think there is an option to enable/disable enhancements, perhaps this is set for maximum compatibility?

John Garza (3665) · (This post was last modified: 08-03-2023 11:57 PM by John Garza (3665).)

29C up and running fine with transplanted memory chip from 25C !
(it's a nice clean one too with white keys - no yellowing)
Now to dig up my Panamatik chip.

-J

Sanjeev Visvanatha · (This post was last modified: 08-04-2023 12:25 AM by Sanjeev Visvanatha.)

Congratulations!!!

My Panamatik 25E has new white keys also, and a very bright LED. So happy with it. The 25 donor was in great condition except a fried ACT and a key that didn’t register (easy fix). It looks new.