RAM-Box, HEPAX, 41-CY... Power requirements.

Hi all,

I'd like to know how much power do those devices need, how long will a fresh battery set last with "normal" usage...

I've been told that they're quite "hungry", but have no accurate info (measurements) about it.

Thanks in advance and best whishes.



Diego et at,

My only experience is with the Advanced HEPAX Module (16k RAM). A new battery set will last from three to four weeks when using it frequently (ROM copies, Hepax file management, etc), and will last for about six weeks if only doing a moderate usage of it (MCODE programming, etc).

Not wonderful, but a small price to pay for the wondrous features and capabilities of this device, really a complete RAMBOX fit into the standard module size.

I understand that the CY and RAMBOXES have an auxiliary battery, which I imagine should alleviate this heavy requirement.




the auxiliary battery of the W&W RAMbox is only used when the calculator battery is empty. So it is only used for safety reasons and if you remove the RAMbox from the calc.

It is a lithium(or so) cell which has only little capacity, nevertheless it holds for many years as it is not really used.

I did not check the power consumption of the RAMbox II yet. But HEPAX really needs a lot. Even in a switched-off calc the capacitor is down much earlier than without HEPAX (if batteries are removed).

But I aggree: HEPAX may be the best device ever designed for HP41 ! The OS is much better than that of the W&W RAMbox ...

Best regards,




For some reason (it may be my crazy head) my previous post in this thread has fallen into nowhere land :-o

It was only intented to thank you both you comments and info on the subject.

I was determined to keep my next project power requirement as low as it can be.

Much work ahead, now it's time for a little rest.

Thanks again and Merry Xmas.


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