What is best module for 41c?


I just got a 41c from a friend. It has the manuals, but no modules. The serial number is 2210S41778. It did not work until I twisted it somewhat (thanks Steve (Australia)). Now it seems ok.

My question: There are a number of modules available for it on eBay. What ones would be the best to get?

(I currently have 48s (S & G), 49G, and 49G+ - this is for fun)



For a 41-C I suggest:

1-Quad memory module
2- MATH/STAT module
3- Advantage Module
4- X-Function Module

Your 41-C would have features liek an HP-41CV plus the extra math & stat features.



Mamir posted,

For a 41-C I suggest:

1-Quad memory module 2- MATH/STAT module 3- Advantage Module 4- X-Function Module

This is a good list (and in fact I have one or two of each of these, along with a 41C), but my ordered list would be the following:

1. Quad Memory module

2. Advantage Pac

3. Time Module

4. X-Function Module

5. Math/Stat Pac

The Advantage Pac contains most of the best features of the Math and Stat Pac's, improves upon others (notably SOLVE, INTEG, and matrix functions), and adds many more.

The Time Module gives capability for a clock, stopwatch, and handy calendar functions. Some application programs make use of these.

The X-Function module gives 124 registers of "RAM disk" storage and the functions to access that space, but not many "everyday" useful functions, unless you are into serious programming. The module can be used to transfer files from one 41C/CV to another, if the swap is done quickly. More convenient than a card reader!

BTW, your having to twist the calc to make it work seems to indicate a broken screw post. This is a very common problem, but it should be fixed -- with glue or "plastic weld", if I'm not mistaken.

-- KS


"The module can be used to transfer files from one 41C/CV to another, if the swap is done quickly."

Thanks Karl. I'm going to have to try that...........quickly.


Hi, Martin;

you have already read two very good suggestions, and I'd endorse the need of a quad memory module. Anyway, please accept two additional suggestions that are, in fact, these `build your own module set` currently available wonders:

Meindert Kuipers' MLDL 2000

Diego Diaz' Clonix/NoVRAM/NoV32 Modules

Seeing is believing...


Luiz, a believer (Brazil)

Edited: 29 Mar 2006, 1:28 a.m.


I suppose there is no universal answer, as it really depends on what you are interested in doing. Therefore, I would suggest you learn something about all of the modules so you are better able to estimate what will be useful/amusing to you.

My choices:

1) The HP Museum CD or DVD. Lots of good stuff about the 41 and peripherals. http://www.hpmuseum.org/cd/cddesc.htm

2) Magnetic card reader, so you can save any important work. This might make the memory capacity of the stock 41C manageable.

3) HP-IL Module and printer. The IL interface opens up some interesting interfacing capabilities.

You could skip the card reader if you arrange another means of storage via HP-IL.


Dear Martin,

now you own the HP41C model - but I prefer the HP41CX which includes complete main memory, X-Function, basic X-Memory and last not least the Time- Module.

To this I add a Double X-Memory Module + CCD-Module + EXT-I/O Module + IL-Module. This is my basic system setup :-)

A nice extension would be the EXT-IL Module, and by using a Clonix from Diego you place nearly the complete module collection above in only one plug in port - and this for a fair price.....

Regards - Christoph Klug


The HP48G emulator module. Also the PPCROM.

Rick in Bel Air, CA

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