Life span of an HP Calculator

[Geoff Quickfall]

(09-13-2024 05:37 PM)KeithB Wrote:  We don't need to litigate it here, but Boeing's problems go well beyond commercial aviation.

I agree.

Cheers

[AnnoyedOne]

(09-13-2024 05:31 PM)Matt Agajanian Wrote:  A more beneficial scenario is that by time the battery is drained, a newer and greatly improved model is available.

Good logic!

That said I made the mistake of buying a cheap calculator as a student. Once.

https://www.hpmuseum.org/forum/thread-20...#pid190587

HP's after that. Probably not these days though.

A1

[Uwe-001]

I own every original HP Voyager calculator twice and every HP Pioneer calculater model usually twice and they all work perfectly without any problems. From a technical point of view, there is hardly any reason why the devices, at least with good care, should not continue to work as long as before.

[lrdheat]

My dad’s HP 35 from June 1973 is on my desk at work. 51 years old, and in perfect, pristine condition. I use it every day at work, it is a treat to have!

[HPing]

We worked in sporting goods in the Voyager era. Plastics and coatings for consumer goods seemed to be innovating rapidly in the 1980s and the makers saw a variety of unexpected failures, some recalled some not recalled.

Some of this seemed to be: poorly-developed chemical engineering, bad raw materials, bad production batches, colour/coatings incompatibilities, unexpected chemical reactions, accelerated deterioration from exposure to light, "air", moisture, variable temperatures, chemical fumes... Some of the failures were never figured out.

We sensed that a lot of the problems were ironed out by the early 1990s.

Generally speaking, where and how equipment was stored seemed to be the major factor for longevity. Dark, dry, cool space away from household chemicals seemed ideal for sporting goods, generally. YMMV.

[Alder Statesman]

I have my Dad’s HP-65 that he bought new when they were introduced. Works on A/C adapter like new including the card reader. That make thsi example one half of a century old.

My son has my HP 48GX I purchased when they came out in ‘93. Still runs like a tank after 31 years.

[John Garza (3665)]

As Geoff astutely mentioned, marketing plays a huge role in most companies. However, I believe the engineers at HP in the early days had more of a say than is typical in most companies. So some cost saving moves were avoided in favor of higher quality (and therefore longer lifespans). The life expectancy of a calculator depends on the model, which is dependent on the design, which in turn is related to the desired focus from a business perspective. And that focus can change over time as businesses continually re-evaluate the marketplace and profitability. Trade offs like: are we selling cheap machines for students to compete with Casio and TI, or high end machines for professionals?

As for me, my oldest machine is an HP-9100B of 1969 vintage. 100% functional including the card reader.

-John

[AndiGer]

(09-13-2024 04:43 PM)AnnoyedOne Wrote:  I was once invited, by a marketing/sales person, to a meeting with a potential customer. After the meeting I said "You know our product doesn't do all those things right?". His response: "That's your problem not mine!" True story.

I suggest this video :-D
https://m.youtube.com/watch?v=BKorP55Aqvg

[AnnoyedOne]

(09-13-2024 06:36 PM)AndiGer Wrote:  I suggest this video :-D

LOL. I was not "the expert" or asked any "questions".

Just a "potted plant" for appearance is my guess

A1

[DA74254]

Anyone seen this? Planned obsolecence or the light bulb conspiracy?
https://www.youtube.com/watch?v=BWJC5ieUAe4

Modern things/gadgets are not made to last. The manufacturers want it to break and have you buy new stuff to keep their revenue going..

I was sort of "late to the party" and my oldest functioning (HP) calculator is the 28S from 1988, still with an intact battery compartment. Though, I've "retired" it and left it without batteries since the last replacement depleted a few months ago. I do have 6 fresh N-cells for when I want to use it.
I have my "mandatory school" (Ground schhol/Elementary school, 9 years "basic school" or whatever you call it around the world) Casio FX-82 from 1983, still with the original 2 AA batteries in it and functional.

My take is that, if something breaks "without reason" after a few years, I don't buy the same brand back.

My first Canon printer "died" after 4 years for no apparent reason, except that the "obsolecence chip" inside decided I needed to buy a new one. Nope, went to Brother. Then they stopped supplying ink to that printer. No more Brother in my house.
Let's see how long the Epson Ecotank printers last..

[KeithB]

"My first Canon printer "died" after 4 years for no apparent reason, except that the "obsolecence chip" inside decided I needed to buy a new one. Nope, went to Brother. Then they stopped supplying ink to that printer. No more Brother in my house.
Let's see how long the Epson Ecotank printers last.. "

When are you going to get around to HP? 8^)

[AnnoyedOne]

(09-13-2024 07:10 PM)DA74254 Wrote:  Nope, went to Brother. Then they stopped supplying ink to that printer.

My Brother laser printer is still functional. I did have to replace the power supply after a surge many years ago.

That said my attitude is pretty much the same.

"Fool me once. Shame on you. Fool me twice. Shame on me".

A1

[Garth Wilson]

(09-13-2024 06:24 PM)John Garza (3665) Wrote:  As Geoff astutely mentioned, marketing plays a huge role in most companies.  However, I believe the engineers at HP in the early days had more of a say than is typical in most companies.  So some cost saving moves were avoided in favor of higher quality (and therefore longer lifespans).

My first programmable was the TI-58c, in December 1981.  My resources were limited, and a calculator's price at the time represented a lot of hours' work's pay.  I collected all the information I could at the time, and although I drooled over the HP's, I looked at the size of the projects I wanted to do, and TI offered the memory I wanted for a price I felt I could pay, unlike HP.  I presented my logic to KeithB who was using an earlier TI programmable (SR-56?), and he said he was holding out for when he could afford the best, the HP-41cv at the time, while going to school full time and working a few hours a week in a hardware store.  Delay notwithstanding, he made the better decision.  I eventually went the HP route too, but it took more experiences to convince me I should.  And now, besides the vastly superior capabilities of the 41, there's the fact that my TI's all have major problems (and keyboards are not one of them).

Geoff Wrote:This all comes down to a new calculator with increasing power every few years. Marketing wants you to purchase a new one and the engineers (initially) wanted them to last and last and last.

The marketing people need to understand that their target market, which in this case is engineers and other technical people, don't think like marketing people.  We buy something like the HP-41cx in the 1980's, read the manuals cover to cover (and don't lose them), get other materials on it like Mier-Jȩdrezejowicz's 1.5"-thick book "Extend Your HP-41" and read it cover to cover, buy other modules and accessories (my own collection dramatically dwarfing the initial price of the bare 41), spend time writing programs for our particular applications, etc., making a huge time investment on something we expect to use for many years.  Technology will keep moving; but we can't afford to start over every few years and make this kind of time investment, even overlapping, and translating and moving our frequently used programs to another platform (especially one that won't last), when familiarity and other fruits of our investment are more valuable to us than the shiny new technology the marketing people want to dangle in front of us.  Now, nearly 40 years after I bought my first 41, brilliant engineers and programmers on this forum are still introducing new things for it.  That doesn't mean faster and more-powerful computers don't have their place.  Of course they do.  The application is different though.  I still use my 41 every day, but the programs max out at about 300 bytes (and are usually less, albeit that the 41 makes very efficient use of user program memory with merged instructions and with the functions in the vast array of modules available today), and although it is slow-running, the time saved developing a custom program on a familiar platform may be more important.

74254 Wrote:Modern things/gadgets are not made to last. The manufacturers want it to break and have you buy new stuff to keep their revenue going.

A supplier gets one chance with me.  If their product doesn't last, I won't buy from them again.  I mentioned having multiple TI's, but that none of them fully work now.  Only one was new though, and the failures on all of them started after I acquired the last one.

[rprosperi]

(09-13-2024 06:14 PM)Alder Statesman Wrote:  I have my Dad’s HP-65 that he bought new when they were introduced. Works on A/C adapter like new including the card reader. That make thsi example one half of a century old.

My son has my HP 48GX I purchased when they came out in ‘93. Still runs like a tank after 31 years.

FYI - Running the card reader on A/C power only is specifically recommend against in the Owner's Handbook. Various theories have been proposed here (which some readers can follow while others can't, but no matter since they're only theories) but the important thing is to let you know you should probably stop doing that. A new battery is a small price to pay to keep an HP-65 that's still being used healthy and safe. Just a comment in case you didn't know.

See pages 87-88, which include this comment:

Quote:Since you cannot operate the card reader/writer without a
charged battery, even with the charger plugged in, the battery
should not be removed while running from the ac line.

[Ren]

A week ago or so, I took the Dollar Tree scientific calculator out of my backpack. I've had it for maybe 10 years.
The battery was dead. The back of the calculator is secured by screws. The label says "No User Serviceable Parts Inside".
Challenge accepted!

[AnnoyedOne]

(09-14-2024 06:34 PM)Ren Wrote:  Challenge accepted!

That reminds of someone I know

A1

[CheshireChris]

(09-13-2024 02:06 PM)HPing Wrote:  I don't know of a failure mode for the old 12c.

Maybe decade-long battery life would be an issue for leaking batteries lol?

The LCD screen is probably the point of failure for most. Eventually it is likely to start to leak fluid and develop black marks.

[Divasson]

HP41c plastic material becomes brittle with the years and breaks easily. This becomes difficult to fix, since the plastic used is not reacting well to glues in general.

I have experienced the worsening over the last 10 years.

[brouhaha]

(09-14-2024 01:02 AM)rprosperi Wrote:  FYI - Running the card reader on A/C power only is specifically recommend against in the Owner's Handbook.

The HP-65 and HP-67 have almost the same design error as the Woodstock series. If a good battery is not present and making good connection, too high a voltage can get to the card reader circuitry. (In a Woodstock, it can damage all the PMOS chips.) I think the 97 may have the same issue. The other Topcat models (91, 92) do not. However, the 91/92/97 will not work _correctly_ without an at least somewhat good battery in place and making good contact.

The other Classic models (35, 45, 55, 70, and 80) do not have this problem.

At this late date, the general advice I'd give is to always recharge the batteries outside the calculator, and generally avoid using the calculator on an AC adapter. The 91/92/97 printers draw so much current that if you're going to print much, you have to have the AC adapter, but in that case make sure the battery is working (powering the calculator properly) before plugging in the adapter.

[teenix]

The 97 (and unreleased 95C) actually have an overvoltage circuit which trips if the battery on charge goes above 6V. It would also work with the battery out of circuit, however you would lose some of the AC ripple dampening effect of the battery should this be removed. The manual mentions improper displays running only on the AC charger, probably caused by the excessive ripple. The charger on its own won't power the card reader and printer properly either. The service manual also mentions AC adaptor only will not cause damage, however the manual also says the battery [must] remain in the calculator during operation.

The 91 and 92 Topcats do not have this over voltage protection. The manual says operation will be the same as the 97 (95C) without batteries.

To preserve the wellbeing of the calculator, the overall consensus is to...
Use batteries in good condition
Keep battery terminals clean - including charger port (Classics, 65, & 67)
Charge batteries externally
Do not use the AC charger, unless charging external

The power switch is also part of the battery circuit so it should receive some maintenance every now and then. Most notably, the original contact lubricant dries up and goes hard.

cheers

Tony