Battery replacement HP75C


Hi all,
Whilst clearing attic space from my parents, I came across an HP75C that had been given to me as a child by my grandfather (who has since passed away).

He was a keen calculator and computer enthusiast and kept his equipment in pristine condition. The unit is still excellent and has sentimental value for me. I have been using it and playing around but have noted that the original batteries are non usable and deteriorated.

What would be everyone's recommendation? My intent is to preserve this as a working piece as well as a potential collector’s item. Would you recommend in investing in getting a working battery pack replacement? If so, having noted several advertisements for providing replacement packs, is there any clear recommendation on this? Please excuse my potential naivety on the subject - I am very new to the HP world.


Hello Chris,

From my perspective you should keep it and replace the dead NiCd AA cells.

You can find more battery information
and here

Now if you want to play with it, I suggest that you connect your HP-75C to HP-IL devices (printer, storage, video, etc).

The least costly would be the to connect the 75 to a PC with the following setup:

a) PIL-Box (HP-IL to USB box from Jean-François Garnier, here)

b) HP-IL cable (needed between the HP-75C and the PIL-Box)

c) USB cable (needed between the PC and the PIL-Box)

d) HP-IL devices simulators (here and here)


Possibly Related Threads…
Thread Author Replies Views Last Post
  HP Prime Program: Sampling Without Replacement Eddie W. Shore 13 3,875 10-04-2013, 12:22 AM
Last Post: Joe Horn
  HP48GX screen replacement Francisco Quiles 9 3,888 10-03-2013, 09:17 PM
Last Post: Francisco Quiles
  HP 2225D+ RAM failure/replacement Luca 4 1,953 09-10-2013, 01:46 PM
Last Post: Luca
  HP 15C-LE replacement still available? Borja 16 5,565 08-22-2013, 11:16 AM
Last Post: Michael de Estrada
  HP 50G battery cover replacement wildpig 1 1,225 08-03-2012, 11:53 AM
Last Post: Tim Wessman
  HP41 post replacement experiment Bruce Larrabee 14 3,588 07-16-2012, 06:51 PM
Last Post: Bruce Larrabee
  Stack Replacement for HP 48SX bluesun08 2 1,401 05-17-2012, 02:35 PM
Last Post: bluesun08
  aOT--Battery/battery contact care advice needed Matt Agajanian 0 1,155 04-24-2012, 07:35 PM
Last Post: Matt Agajanian
  Hp 12C replacement bezel James Nelis 0 868 04-06-2012, 06:37 AM
Last Post: James Nelis
  19BII replacement recommendations/decision making help needed Timo Labrenz 20 4,934 03-28-2012, 12:24 PM
Last Post: Timo Labrenz

Forum Jump: