HP-41CV battery replacement

[Volker Neurath]

Hi folks,

I know that this is not quite what the group's theme is but I rather don't
know where to ask else...

I had the luck to find a working HP 41CV and since saturday I can call it my
own. I'm studying the "owner's handbook" on www.greendyk.nl since then but
one thing I find not explained that well:

how to open battery compartment.

Anybody here who can explain?

Regards
volker
--
Im ï¿œbrigen bin ich der Meinung, dass TCPA/TCG verhindert werden muss

Wenn es vom Himmel Zitronen regnet, dann lerne, wie man Limonade macht

[Joe Horn]

> how to open battery compartment [of an HP-41]

The battery holder has a large indentation at its top. Press your thumbnail into the indentation, then push upwards (towards the top of the calculator), to slide the entire battery holder upwards. The bottom of the battery holder will pop out.

-Joe-

[Volker Neurath]

Joe Horn wrote:

> The battery holder has a large indentation at its top. Press your
> thumbnail into the indentation, then push upwards (towards the top of the
> calculator), to slide the entire battery holder upwards.

I did.

> The bottom of the battery holder will pop out.

This didn't happen and that's the reason for my question.
But I managed by putting a small screwdriver in the lid opening when pushing
battery holder upwards and using the screwdriver as a lever.

Anyway, thanks for your answer.

Volker

[Joe Horn]

> I managed by putting a small screwdriver in the lid opening when pushing
> battery holder upwards and using the screwdriver as a lever.

Strange that this was necessary. The springs in the battery holder push the cells against the contacts and provide the force that is supposed to make the bottom pop out when moved upwards. I can only think of three possible explanations for the battery holder not popping out:

(1) There were no cells in the holder when you tried to remove it. In that case, you have to pivot it out manually, as you discovered. However, with practice it can be done with fingers alone. OR...

(2) The springs are bent or weak or damaged, and do not provide the pressure necessary to make the holder pop out properly. OR...

(3) Something is making the holder stick inside the calculator, like a foreign object or piece of adhesive tape or gunk, or damage to the plastic somewhere.

I can't think of any other possibilities. Are any of these possible?

-Joe-

[jameslu...@gmail.com]

(4) Batteries are in the holder but swelled to longer than stock length, preventing the holder from sliding up enough for its bottom to clear the '41 case and emerge. Either higher force to compress the batteries or disassembling the '41 to remove the batteries that way may be necessary. If this is the problem, the batteries likely released their caustic contents and have damaged the '41 internals as well. I *really* hope that's not the case!

[Volker Neurath]

Hi Joe,

Joe Horn wrote:

> I can't think of any other possibilities. Are any of these possible?

This i'll have to investigate.
I call that calc my own for less than two weeks ;)
(But managed to code my first programm - a simple one but anyway ;) )