HP 10c

[Stefano2018]

Dear Sirs,
I bought an HP-10c calculator in 1982 and it is still working properly.
I would like to know what can be an estimate expectation life for these calculators (i.e. 40 years or more ?).
Thank you for your attention on this matter.
Regards,
Stefano

[Valentin Albillo]

(05-22-2018 01:42 PM)Stefano2018 Wrote:  Dear Sirs,
I bought an HP-10c calculator in 1982 and it is still working properly.
I would like to know what can be an estimate expectation life for these calculators (i.e. 40 years or more ?).
Thank you for your attention on this matter.

Welcome to this forum, Stefano2018.

I own an HP-10C calculator in fine shape and it's been working flawlessly since 1982, i.e. 36 years as of today. It doesn't show any signs of deterioration or aging (display bleedig, dry capacitors, keyboard malfunctions, etc.) so I'd say it will last at least 10-20 additional years if properly kept.

V.
.

[grsbanks]

How long is a piece of string?

It all depends on two factors:

1) How well you take care of your calculator

2) Pot luck

[Thomas Radtke]

(05-22-2018 02:39 PM)Valentin Albillo Wrote:  I own an HP-10C calculator in fine shape and it's been working flawlessly since 1982, i.e. 36 years as of today. It doesn't show any signs of deterioration or aging (display bleedig, dry capacitors, keyboard malfunctions, etc.) so I'd say it will last at least 10-20 additional years if properly kept.

I read about this kind of guessing (based only on how long something has been in existence already) in the german edition of the Scientific American, but cannot remember how it works. Can you give me a hint?

[Stefano2018]

Thank you all for the answers!

[Valentin Albillo]

Thomas Radtke Wrote:I read about this kind of guessing (based only on how long something has been in existence already) in the german edition of the Scientific American, but cannot remember how it works. Can you give me a hint?

No, sorry, I haven't read anything about it, it's just a (hopeful) guess on my part. Crossing fingers and all that.

Regards.
V.

[EdS2]

(05-23-2018 11:29 AM)Thomas Radtke Wrote:  

(05-22-2018 02:39 PM)Valentin Albillo Wrote:  I own an HP-10C calculator in fine shape and it's been working flawlessly since 1982, i.e. 36 years as of today. It doesn't show any signs of deterioration or aging (display bleedig, dry capacitors, keyboard malfunctions, etc.) so I'd say it will last at least 10-20 additional years if properly kept.

I read about this kind of guessing (based only on how long something has been in existence already) in the german edition of the Scientific American, but cannot remember how it works. Can you give me a hint?

I may have read something similar... I think it's this:

Quote:The Lindy effect is a concept that the future life expectancy of some non-perishable things like a technology or an idea is proportional to their current age, so that every additional period of survival implies a longer remaining life expectancy

- https://en.wikipedia.org/wiki/Lindy_effect

[jebem]

(05-22-2018 02:40 PM)grsbanks Wrote:  How long is a piece of string?

It all depends on two factors:

1) How well you take care of your calculator

2) Pot luck

I agree.

From my experience in the field, any kind of electronic component can eventually fail given enough time, either at rest (not in use) or under load.

There are many factors to contribute to component failure.

Some components can fail after running for a few minutes or hours if the manufacturing process have left higher than acceptable contaminants inside the structure, specially when we talk about integrated circuits.
So when a machine is brand new, it is crucial to use it as long as possible to make sure that all the components are free from obvious manufacturing defects.
If it work flawlessly for months, then probably it will continue to work for many years before eventually failing.

Also, the probability of failure increases with operating temperature (overheating).
The higher the current we force in a semiconductor, the higher the chance of failure.
One such example is overclocking a system that not only can cause soft errors (a power cycle would reset the system to normal) but also cause hard errors (permanent failure due to a faulty component).

Other components will fail for sure in a relatively short period of time (5 to 20 years), like electrolytic capacitors and batteries, as the electrolytes can dry over time or even leak.

[Thomas Radtke]

(05-24-2018 09:57 AM)EdS2 Wrote:  I may have read something similar... I think it's this:

Quote:The Lindy effect is a concept that the future life expectancy of some non-perishable things like a technology or an idea is proportional to their current age, so that every additional period of survival implies a longer remaining life expectancy

- https://en.wikipedia.org/wiki/Lindy_effect

I think it was based on the Lindy effect. Thanks a lot anyway!

[Rogier]

Compare it to us humans. From the day you are born your life-expectancy goes up with every day you survive. At first rapidly, later steadily slower, but even an 80-year old has a a life expectancy of a few years. It never goes down, but in the end we all die.

Similarly all calculators will eventually fail. No predicting when (except if obvious "defects" develop). 36 years is a respectable age for a calculator, but if it's healthy, who knows how long it can last if taken good care of.

[Valentin Albillo]

(05-25-2018 06:31 PM)Rogier Wrote:  36 years is a respectable age for a calculator, but if it's healthy, who knows how long it can last if taken good care of.

The problem is, no matter how good care you take capacitors will eventually dry out, the LCD display will bleed, and the calc or device (old VHS-C camcorders come to mind) will be dead for all purposes except being used for parts.

That said, proper care does do wonders: I still have one of the very first Sony Discman portable audio CD players which I was presented with in the very early 80's, so it's 35+ years-old right now, and still looks mint and works flawlessly. Same with my extensive calculator collection, digital and analogic cameras, old computers, evey kind of electronic device in fact.

Have a nice weekend.
V.

[KD8TZC]

I have a HP45 (different series than yours though) that was made in 1973 still going strong, as well as a HP16C that was made in 1982 that I still use. I also have a 17BII, which is one of my newer calculators (1999) that is having keyboard problems.

My point is sometimes the age of the unit is not always the culprit, but the quality of the unit, or just plain old luck. I believe that in 1999, the calculators that HP made were still high quality pieces of equipment, but maybe not as high of a quality as the earlier ones, but who knows.

[Thomas Radtke]

(05-28-2018 02:40 PM)KD8TZC Wrote:  My point is sometimes the age of the unit is not always the culprit, but the quality of the unit, or just plain old luck. I believe that in 1999, the calculators that HP made were still high quality pieces of equipment, but maybe not as high of a quality as the earlier ones, but who knows.

HP switched to plastic domes in 1985 (18C was first IIRC). I imagine this, along with the replacement of screws by heat stakes, is a significant loss of quality, but at least makes those units less serviceable. But still, those units are going strong today.

Since 2007, I have a RoHS compliant 35s, still waiting for it to fail, but it actually refuses to do so after more than 10 years .

I start getting some trust in modern electronics. Very much to my surprise.

[rprosperi]

(05-28-2018 04:16 PM)Thomas Radtke Wrote:  Since 2007, I have a RoHS compliant 35s...

Aren't they all RoHS compliant ?

[Thomas Radtke]

(05-29-2018 12:18 AM)rprosperi Wrote:  Aren't they all RoHS compliant ?

I think so.