EEVblog #582 - HP41CV Calculator Teardown

What's inside a classic 1979 vintage Hewlett Packard HP41CV "halfnut" calculator?
Should Dave totally destroy it, or respect such a fine machine?

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[TheEPROM]

I would vote preserve it. These things are not common and there wont be much on the other side of the PCB.

[Gyrxiur]

Don't break it, it doesn't deserve it.

[hankus]

Leave it, pictures of the other side can be found online as noted below.

[NorbertHarrer]

EEVblog Please keep the calculator intact. I would rather see a brief video about how to program that thing. Thanks for all the great stuff you do.

[Joe__Tech]

The most beloved calculator of my life. Still using one HP41C from Ebay today an HP42S and the HP42 App

[TehHijack]

Don't drill a piece of history dave!

[Mark.Brindle]

My first was a HP-25C, a present from my parents in '77 for getting into mechanical engineering at UNSW. It lasted me till 83. It was old by then but I just loved it. My first programmable computer.

[DjResR]

I vote for preserve it. It's almost as old as I am (42nd week 1987) and rare specimen of it's kind. There is plenty of stuff to tear apart, modern CFL's for instance (prepare for horror though if you open one apart).

[HighTechLab]

Dont go any further dave, that thing is a beauty!

[CurtCameron]

I still have my 41C from 1981, and it still works. I don't blame you for not ruining it - I certainly wouldn't want anyone to break mine.

[THEtechknight]

Leave it alone. Its nice as it is, and useful.

[jamesgrimwood]

Don't bother taking it apart further. We've seen button matrices before, and you can pretty much figure the rest out by looking through the board itself.

It'd be more interesting to see it working - show us the features that made it last 10 years. I.e explain why a programmable calc is better than some crappy Casio we can buy for £5.

[mikedjames]

I managed to get one of these calculators when my employer told me I could have a calculator for my job.
It was really good and had a lot of cool features.

[zaprodk]

Don't destroy it. I have a 41C where the previous owner forgot to remove the batteries, so the Flex and PCB contacts are destroyed - It's destined for the bin in that shape, unfortunately ... Also, the electronics is a whole lot different. I could send it to you Dave? You can destroy that one without problems.

[tubical]

PLEASE, Dave -- leave this beauty in working condition.
As we can easily obtain a defective unit cheap on ebay, for complete teardown anyway..;)

[ChipGuy]

I vote to respect this thing ! Don't take it apart further.
There is obviously some space for a side power connector or something. Interesting.

[TheNamesGunk]

Preserve it. I doubt it'll be worth it underneath to destroy it.

[UberAlphaSirus]

Don't do it Dave!
There must be a dead one somewhere to butcher.

[CalculatorObsessed]

Glad you kept it together. There are so many ones where the case has got brittle and compression joints failed or damaged by leaky batteries. it’s good to keep a good one intact.

The earlier ones had a separate board with discrete components, connected, and flex/ zebra connection to the keypad PCB. Less reliable as the plastics fail.

There seems to be a bit of a cottage industry in producing parts to repair/ upgrade these.

[nanoheal]

i realy liked how you hold back to destroy such a great device, especially in a teardown video