Decisions Decisions....

[Sanjeev Visvanatha]

(08-03-2023 06:48 PM)rprosperi Wrote:  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?

I have the latest version of the Extended ACT. Looking at the manuals, there does seem to be a difference between the WLP and the Extended's Continuous memory.

[John Garza (3665)]

OK Sorry for the delay everyone - just wanted to give an update.

1) The 29C is just fine with the donor RAM chip from the 25C. Now a pristine example.

2) On the 25C, I had placed a resistor across some pins of the ACT years ago - a temp fix attributable to Katie W. So, it was the likely candidate for the Panamatik upgrade -however- in my less cautious youth (1990's era) I was too forceful in cleaning the keys via the PCB holes, and I actually punched a hole in the keyboard metal strip under the '5' key. That key was no longer operational.

So..The arduous task of repairing a Woodstock keyboard yet again. I shaved off the tops of the heat stakes. And luckily the damaged keyboard metal strip had opened up like a flower blossom. I gently pushed the petals together to close the hole, and topped it off with a drop of solder. While in there, I cleaned and re-lubed the slide switches and scrubbed under all the metal strips and flushed with de-oxit. I then reassembled, and used water activated gorilla glue on all the heat stake tops being careful to spread it around a couple of millimeters on the surrounding PCB to help anchor the PCB as the original heat stakes did., let dry overnight, and the keyboard now works perfectly.

I then removed the old ACT and installed the Panamatik chip in strip headers, the Ir LED, and the GPS module with its power supply. Of note, the GPS module did not have the color coded wires as shown in the manual - just thin copper wire. I tested with an Ohmmeter and they are covered with a clear insulation - so they are not just bare wires that could possibly short if they touched a solder pad on the PCB.

Everything tested OK, I downloaded the NIMB game from the internal library to local RAM, listed on the HP Ir printer. I received signals from 7 satellites, indoors no less! I took the lat/long values given and gave them to google maps, and my house popped right up. Excellent.

Overall, I'm impressed with the Panamatik chip. Though you need to keep the quick reference card for it with the calculator, at least until you memorize the commands. It's not as user friendly as the Teenix upgrades that have a menu system.

The 25C lives again!

On the personal side, the 25C was my 'first love' in HP calculators. I had a summer job while in high school saving up to buy one. I subscribed to the PPC Journal back then and saw an ad for a used 67 by a fellow member - So I ended up buying the 67 instead of the 25C. I also got some PPC back issues, the Math Pac and some cool mods in the deal. The 67 had 2 magnetic reed switches installed. The switches were activated by passing a magnet over the switch located just inside the case. Much better than drilling holes for external switches. One was the mag card write protect defeat switch. Though I removed that and used the Kemper correction card instead - thinking it was not a good idea to deal with magnetic cards and a magnet at the same time! The other was a block 3 access switch - commonly called a 'Black Box'. I actually built a few Black Boxes - which you connected to the power port, but having it all internal was a cleaner solution. I leaned a lot playing with that!

All the Best,

-J

[Matt Agajanian]

I’m casting a vote for the 29C in the ballot box.

Much more capability. Plus:

Indirect addressing
Three subroutine levels
Double the program steps
Looking at the application packs, the 29C has much more potential
Constant Memory
30 data registers
and that’s for starters

[John Garza (3665)]

All true!

But the real truth is any 'serious' programmable needs mass storage.
The programming paradigm on the 29C is great - like the 67.
But even with 98 steps, if you do serious programming, you will frequently find yourself keying in code, and laboriously checking it before you use it for anything meaningful. A terrible waste of time.

Loading in a new program from a mag card in 2 seconds from your personal library of pre-written and pre-tested programs is the way to go.

That's why a 25C is OK for me to use as a 'light duty' machine. I never use it for heavy work. Only the occasional off the cuff formulae in 'straight-line' programs. Something today's general solvers do much better without programming.

A 29C is also a 'light duty' machine as it has no card reader. More capable, true. But that capability is rarely used. If I need that, I usually reach for 65/67/97. The 29C, with it's more powerful programming paradigm will tempt me to write a meaningful program on it, only to be eventually lost. Much better to do it on a 67 and commit it to a card for later use.


But, hey, I repaired them both!

-J

[Namir]

The 29C definitey!! More power .. labels, subroutines, and so on.

[johnb]

(08-03-2023 11:56 PM)John Garza (3665) Wrote:  29C up and running fine with transplanted memory chip from 25C !
(it's a nice clean one too with white keys - no yellowing)

Photos! Or it didn't happen. ;-D

But, seriously, congratulations!
The only thing better than stuff-that's-working, is stuff-that's-working-and-is-pretty!

[John Garza (3665)]

Not to mention stuff that looks good and was sitting in a parts box for years!

   

[johnb]

(10-05-2023 05:13 AM)John Garza (3665) Wrote:  Not to mention stuff that looks good and was sitting in a parts box for years!

Wow. Looks like it's practically new!

The only way to know it's been decades are those lovely red LEDs.