Long Term Storage of HP 41C

[Stoiker]

Hello All,

I bought my HP41C in 1983 (I guess) when I still have been studying. Later I didn't use it very much as it was much too powerful for the calculations I have had to do for business purposes. But from day 1 I love my HP 41C and would like to keep it functioning as long as ever possible.

Now since more than 30 years I keep him with batteries installed and switch him on every couple of months just to check if he is still fine. If the batteries are getting weak I replace those. But last replacement was done for sure approx. 15 years ago.

Now I would like to replace those batteries even though they still seem to be OK because I'm concerned they may collapse because of age. But then the question came up whether it isn't even better to keep him stored without batteries to take away any risk associated with batteries?!

Does anyone know what the best and safest solution is for long term storage? With or without batteries?

If it matters: I have installed Quad Memory, MATH 1 and STAT 1 module.

Thank a lot for any competent respond!

[Dave Frederickson]

Batteries leak corrosive chemicals and destroy calculators and flashlights when left installed. Just check out all the battery damaged 41's on eBay.

NEVER store your calculator with the batteries installed.

[hth]

Just remove the batteries and leave them outside. It is not a car with moving parts, it is electronics.

Humidity, sun and such matters is what may need to be considered.

I had similar worries about my HP-41CX in the past, I feared using it as it might break over time. I could not think of a life without it. So I got a spare when NIBs were offered on the market.

Then I thought, if I now use it and it breaks, then I have a spare. But, if it breaks, I only have the spare! So I would be back to square one, worrying about using the only working one. So i did the only sensible thing, I got a spare for the spare!

Now I have 3 HP-41CXs (and my old CV repaired and converted to a CL) and they all work. I even realized it was no point in keeping the spares in the drawer, so I just use them (well, one so far), hoping that at least one of my four HP-41s will outlast me.

Håkan

[Giancarlo]

Hello,
I usually use prosorb or artsorb silicagel conditioned at 50% of relative humidity. I know that this represent a high value for metal preventing oxidation but i don’t have any info on the best relative humidity for electronical components.

I also think that calculators are emitting pollutants like any other modern (and not only modern) artifacts. For this reason i also use charcoals (a blend of them actually) to absorb these pollutants.

Not far in the future i will be able to measure some pollutants emitted by calculators. Unfortunately i won’t be able to do a full gas chromatography but i will be able to measure the VOCs emitted as whole including SOx and NOx.

Thanks

Giancarlo

[pier4r]

(09-30-2017 01:25 AM)hth Wrote:  Then I thought, if I now use it and it breaks, then I have a spare. But, if it breaks, I only have the spare! So I would be back to square one, worrying about using the only working one. So i did the only sensible thing, I got a spare for the spare!

When I buy valuable things I try always to buy: what I will use, the backup, and the backup of the backup. It is obvious.

Only thing that does not follow this are keyboards. I still have to see a keyboard failing (unless stored under weight).

Mine got wrecked a bit in the < > | key (it is only one key, on a German layout) due to improper storage during a moving, but it is still works. I guess I used it since 5 years now.

[Stoiker]

All,

thanks for your quick response. I will follow your recommendation and remove the batteries immediately.

Thanks!!