Working HP41C With no PCB Board?


I have opened many HP41C/CV/CX's but I have never seen one without the PCB board. I just opened one with the PCB board built into the key/display board. Has anyone ever seen this? If anyone would like to see a picture let me know.


It has an IC right where the pcb used to be.


Would that make it a no-nut?

Post a picture to the forum!


I have posted the pictures


That's neat! I haven't heard anything about these. Is it a CX? What is the Serial Number?


The calculator is a HP41C with a scratched on serial no. 2223S44044. It is lighter than the others also.


Dear Ty,

That looks really neat! You said this is a C, so is it possible that this unit was originally a Fullnut C that was sent in to HP to be fixed, and they upgraded it to the Halfnut C equivalent? That would make it very rare. Is the screen rounded or squared off at the corners?

I mention this because a CX Halfnut that I have looks a lot like your picture, but it has a bigger chip. I would love to see a picture of the front of your C.

Where did you find this thing, by the way?

Best regards,

Ion Abraham
Albuquerque, New Mexico



A picture of the front has been posted. As you can see in the picture the display is rounded. I got it on Ebay. I guess it was repaired by the way the serial no. has been scratched in on the back. Who knows.


The last one I just had one of these in a CV variety. My guess is that this is simply reduced electronic versions.

I don't think they are all that rare.


So do we now have the full-nut, half-nut, and the no-nuts?

Now I've got more to collect.

How about blank-nuts, half-blank-nuts and no-blank-nuts?

I'm going nuts just thinking about.

"I've got a lovely bunch of coconuts"
"There they are all sitting in a row"

This is steve's other half. The men in the white coats are coming soon. Don't worry dear.


Another late follow-up - I just don't find the time to keep up here :-(

Ty's No-Nut is definitely from an HP-41C sent for repair to HP, who replaced the entire calculator with a Halfnut unit and scratched on the serial number of the original HP-41C sent for repair.

These _are_ rare - the HP-41C was no longer on sale when the Halfnut version of the HP-41CV and HP-41CX was put on sale. So the only way to get a Halfnut HP-41C is to find one of these replacements.

How many people will admit to having one? I was extremely lucky to get one froma fellow collector to whom I am very grateful!

Wlodek Mier-Jedrzejowicz


It sounds like a 41C that I had sent back to HP for repair in the mid 80's. It came back with the brains and memory of a 41CV (and a note not use use memory modules). Case still says 41C and has the original serial number. I wonder what other mutants are out there?

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