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dhe · 03-29-2021, 08:56 PM

About 9 years ago, I bought an HP-97 Desktop model from Goodwill for the princely sum of $19.00 dollars.

I finally pulled it out of storage. It had a little 82059D transformer with it, looking at past messages that appears to be correct.

I pulled the batteries, they have a little sticker that say 3/1987 - surprisingly, very surprisingly, didn't I mention I was totally surprised? The battery pack say 3.8V.

I plan on putting all this together and letting it charge for 24 hours. Can someone tell me what the battery pack should report when fully charged?

Thanks,

Dave Britten · 03-29-2021, 09:10 PM

The pack contains 4 sub-C cells, so somewhere around 5.2 volts for 4 NiCds at 1.3 V each.

Dave Frederickson · (This post was last modified: 03-29-2021 09:49 PM by Dave Frederickson.)

From the 97 Service Manual, here're the specs for the 82033A battery pack.

Four cell, 4.4 to 6.0 volts, quick-charge, nickel-cadmium battery pack.
• Operating time: 3 to 7 hours.
Note: Battery must be in place to operate the calculator.
• Recharging time: 7 to 10 hours, calculator OFF; 17 hours, calculator ON.

The troubleshooting flowchart states that the no-load voltage from the battery should be at least 4.4V. Your 3.8V battery, is that what it measures or is that marked on the battery?

It's rare that original batteries are still good. If you need a replacement, here's a source.
https://www.ebay.com/itm/2200mAh-NiCd-Ba...4091690362

Dave

dhe · 03-29-2021, 10:49 PM

Apparently Franken Batteries, 3.8V on the battery, no charge for 9 years.

Dave Frederickson · 03-29-2021, 11:42 PM

I'm surprised it ever worked. I recommend the replacement battery.

dhe · 03-30-2021, 08:49 PM

4.9V after charging for 10 hours off, I didn't test run time.
Unit powered on and did some simple math.

Does anyone know of a source of diagnostic cards?

Thanks,

Dave Frederickson · 03-30-2021, 09:11 PM

(03-30-2021 08:49 PM)dhe Wrote: 4.9V after charging for 10 hours off, I didn't test run time.
Unit powered on and did some simple math.

Does anyone know of a source of diagnostic cards?

Thanks,

Good luck with the battery. Smile

The HP-97 Diagnostic is part of the Standard Pac. I saw several Std Pacs on eBay at ridiculous prices.
NOS/used mag cards can also be found on eBay. A few years ago I found several NOS packs of cards on eBay for about 50 cents per card.

AndiGer · 03-31-2021, 08:43 AM

(03-30-2021 08:49 PM)dhe Wrote: 4.9V after charging for 10 hours off, I didn't test run time.
Unit powered on and did some simple math.

Does anyone know of a source of diagnostic cards?

Thanks,

SD-15A is also printed inside the Standard Pac manual. SD-15C is different.
Look here for SD-15A http://www.prevelakis.net/HP67/HP-67-Diag.pdf
and some discussion to SD-15B here https://www.hpmuseum.org/forum/thread-7873.html
Maybe you can find SD-15C as well

Andi

dhe · 04-01-2021, 08:40 PM

I have my eye open for a standard pac, I'll just have to wait until one comes up.

What is or is there an easy way to duplicate magnetic cards?

Thanks,

PS.. I've also put my name in to purchase a PIL-Box, when they become available.

Dave Britten · 04-01-2021, 10:38 PM

(04-01-2021 08:40 PM)dhe Wrote: What is or is there an easy way to duplicate magnetic cards?

On the 97? Just read in a card, switch to program mode, and write out a new copy.