EEVblog #582 – HP41CV Calculator Teardown

What’s inside a classic 1979 vintage Hewlett Packard HP41CV calculator?
Should Dave totally destroy it, or respect such a fine machine?
Forum HERE

More photos of the removed PCB are HERE

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  1. I vote leave it intact.

  2. Second vote for leaving this machine intact.


  3. Yeah, nothing really gained by destroying it.

  4. Leave intact; otherwise the magic smoke will leak from something else HP in your lab.

    Not that I’m superstitious or anything..

  5. There is no other chip underneath – it’s just the contact pads for the keyboard. No need to break it further apart!

  6. I would not pull it apart. Best to go to…

    …and you will see the insides.

    In my day, you were either a HP or TI fan. I was the latter. I hated RPN – its frogshit.

    I used to have a Texas Instruments SR-56 bought in 1978. Cost me a fortune. It last 6 months. I left in in the boot after uni one day and the wheel jack rolled into it and demolished the keyboard PCB. It was beyond repair.

    • god is a delusion

      RPN is great! The dinosaurs who found it too difficult are the same ones who can’t understand why the Metric system is superior..

  7. We grant a last minute reprieve to spare its life.

  8. Respect the quality of design and construction, leave it in good condition.
    RPN forever.

  9. Go and ask the dentist to x-ray it.

  10. Hi Dave,
    What about a teardown of the expansion cartridge?


  11. Find a broken one, and tear that one down to your heart’s content.

  12. With so much of the good quality lost nowadays with crappy design products and “skinning a turd” ethos that so many companies hold close to their hearts, best to keep hold of the things that were well made… I vote for keeping the unit intact!! 🙂
    Keep up the good work Dave…

  13. Don’t do it!

    Poor girl never did you any harm, there’s no reason to kill her 🙂

  14. Don’t do it Dave…

  15. I still have my 41CV bought it back in the late 70’s early 80’s it was the most advanced hand held in existence I also have the tape drive the IL loop and the 82162A thermal printer used to have the card reader and wand.
    Used a Texas idiots calculator once threw it in the trash where it belonged. As far as the modules go there’s nothing to see inside unless you like looking at a blob on a PC board.

  16. Oh yea only an idiot would like a Texas idiot calculator!

  17. Please leave the 41CV intact!

  18. Nice partial teardown. I enjoyed that.

    Do NOT detach the PCB from the keyboard. Wait until the machine no longer works before showing us the PCB top side. Yeah, I know, it’ll take another 350 years before something renders it nonfunctional. With all those gold contacts, and with what little use the machines sees, it could well be another 3500 years!

    Dave, you’ve given me incentive to find my old HP41CX calculator from 1986 & see if it still works. I’m sure it does! I bought it back when absolutely NOBODY had a computer. Nobody I knew anyway.

  19. Hi. Leave it alone 🙂
    Do not destroy it.
    But maybe take some X-Rays of LCD area!

  20. By the way, there are several nice images of this calculator in google image, showing the precursor versions! Great to see and compare the design evolution. Take a look.

  21. I loved my ’41, I wish I still had it. Cherish it and leave it intact.

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