HP-41C with no serial number


Hi everibody,

Thank you for this beautiful forum !

I am not really a collector but I have some programmable HP RPN calculators which I use daily because I think they are still the best (I'm in marketing).

I have a HP-41C bought in 1980 (if I remember) that was sent about 8 years ago to an Italian HP dealer for repair (and I was told that it was sent to HP, I waited two months to have it back!). It came back with no serial number and no indication of where it was manufactured. There is a gold line around the keypad and the block of the overlay sheet is not on/off type like the original but there is a spring. It is in mint conditions and I wonder to know if it is a collectible item and the value, even if I won't never separe from it !

Thank you in advance and best regards,



I have seen some HP-41-C' made in Singapore with no serial number stamped into case, but they had a silver decal/tag with the derial # located in the battery compartment. It could be that your calculator is missing this tag.


Thank you for the reply.

I don't have a tag in the battery compartment, I have seen only now that there is a small "made in USA" on the yellow tag on the back of the calculator with the explanation of the Alpha shifted keys. The fact is that when I sent the calculator for repair it had a stamped serial number, and therefore they have certainly changed the case.

anyway, the nice thing is that i use this calc almost everday and it works very well. I only had to clean the contacts and replace the batteries some days ago !

Best regards,




If the colour of the trim is yellow, then your calc might be a CV. BTW many S/N less calc have been reported lately (see previous forums)

I suggest you to check this site to estimate value, as many sources might give various and inconsistent quotes.

There are many 41 c's for sale, but as for most of us this is an item that bears more sentimental value and hence is difficult to quote.


It was very common for HP to replace repaired machines with units that had no serial number. They usually hand-engraved the old number on the replacement unit, but were often a bit lazy. Also a lot of repaired 41C machines came back as 41CV units internally.


You should be able to distinguish the HP-41C from the 41CV by the amount of memory it has available. My CV has serial number on upper back panel on the flat shiny surface.



(to all)

Thank you very much for the answers. The calculator is a C because of the memory available, unfortunately it came back from the repair without the CV memory!

Another question, please: I know that there where many threads about this subject, but I don't remember if there are in this century other manufacturers of RPN calculators than HP.

Best regards to all,




AFAIK only 'HP' still produces an RPN calculator in this century.

Other (last centuries) RPN calcs from other brands include
Commodore (~Privileg),
the 'Novum 650 MathBox',
and maybe the Curta's.




I forgot to mention the Russian brand Elektronika,
which produced some RPN model, too.



Many thanks !

I have now finally understood that i have to start a collection !

Best regards,



Re other RPN calculators: My first scientific calculator (1973) was a Sinclair Scientific, which I bought in kit form. The dreadful thing had no x<->y key, making it necessary to write down intermediate results, so during my Easter holidays from university, I got a job as a barman and saved enough to buy an HP-45. Bliss!

The earlier Sinclair four-bangers were powered by two AA batteries, and had quite a slim case. The Scientific required a 9V battery, and rather than redesign the case, they simply had a huge bulge in the battery compartment door at the back! Horrible design, but for GBP19.95 in kit form, it was great value.

I believe National Semiconductor also had some RPN models.


--- Les [http://www.lesbell.com.au]


this is a list of non-HP rpn calculators that i coppied from guy ball's website, with two additions:

Rechargeable or Disposable Battery Powered Models
APF: Mark 55
Commodore (USA): MM6X (just the "X" version, not all)
Corvus (USA): 500
Elektronika (Russia): b3-19, b3-21, b3-34, mk-54, mk-61
Magiclik: 306
Montgomery Ward (USA): P10
National Semiconductor (USA): 600, 900, Mathematician, 4615, 4640
Novus (later name for National Semiconductor brand): 650, 3500 Sliderule,
4510 Mathematician, 4515 Mathematician PR, 4520 Scientist, 4525 Scientist
PR, 6035 Statistician PR.
Omron (Japan): SR12
Prinztronic: Programmable Scientific
Privileg: Beginner, SR-54NC
Santron (Japan or Taiwan): 12S, 604
Sinclair (England): Scientific, Scientific Programmable
Super Cal(??): 616
T.I.: there is an rpn emulator rom for the TI-58 and TI-59

AC / Line Powered Models
Anita (Sumlock Comptometer of England): 1011 LSI
Bell Anita: 1011
Friden: EC130, EC132, 1151, 1152, 1160, 1166.
Garrett: all
Monroe: EPIC 3000

i have three. the comodore is a four banger. the novus mathmatician is a kind of cheaply made hp45 with inexact trig functions. that garrett is a tank and has wood sides and great keys. it's an instrument that could "sit with perfect aplomb on your chipendale end table".

an interesting aside; dave hicks once told me that unix ran a program called "dc". it was an rpn "desk calculator".


I believe the Panasonic HHC had a scientific calculator module that was Reverse-Polish and it had more that a four register stack.


i think i've seen them. weren't they a 71 shaped calcer with a cradle for memory and printer? so was the module a chip you pluged into that semi exposed pcb?


Yes, that sounds like the HHC. It used a 6502 with a power up, power down scheme to save battery power.

I considered getting an HHC, but the 41 won (of course). Also, the 41 with its card reader could read in my 67 programs and translate them into FOCAL. After the 41CV, I owned a 48SX with the 41CV emulator ROM card and it could run my 41 programs in a '41 environment.' Currently, I use a 48GX and a 32S II (and a 27S (oops, not RPN) :-) ).


The HHC may have an RPN module, but I guess it's *really* hard to find. There is a built-in calculator, but you would not like it. Also a BASIC module exists, rare again...

On the Novus 4510 Mathematician, note that the stack has only 3 levels, there is no Last X, the Z level is not duplicated on drop-down of the stack (it's zeroed), there is no roll up or down, and scientific functions (trig, log) clear the Z level !! All this plus the imprecise calculations make it a very funny and pleasant calc ! Wow, talk about vintage.

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