Question on HP41CV


I recently purchased a HP41CV Blanknut from a guy who said it had been stored away for the last 15 years.
The buttons have a nice feel to it, but I have a problem with the on/off switch.
It is not as soft as the user/ alpha or program keys.
Could I spray it with something?
Or will it have to be opened?


I have sprayed from behind the switch, through the tiny hole with a good quality circuit board cleaner with good success for this kind of problem.


Thanks John, So I would need to open the calculator or can I spray it from the outside?
Thanks again,


I opened one of my HP-41 series and I gained access behind the keyboard. All the keys are absolutely sealed (see this photo: and very different from the "Clasic" series keys, so in my opinion to spray anything should have no effect.


from the inside with tv tuner cleaner. carbon tet works but it can bleach out the keyboard face.



You need to open the calc, lay it face down, locate the small hole behind the "switch" if interest, and give it a squirt through the tube you get with spray pacs. It may not be immediately better, in fact it may be worse initially, but some "exercise" will make it as good if not better than before, hopefully better !!. Cheers - John

Possibly Related Threads...
Thread Author Replies Views Last Post
  hp41cv memory modules tim peterson 10 1,768 11-07-2013, 11:09 PM
Last Post: Garth Wilson
  HP41CV Mike Powell 12 1,713 10-30-2013, 08:17 AM
Last Post: Mike Powell
  HP41CV Bry Sun 11 1,792 10-22-2013, 12:52 PM
Last Post: Geoff Quickfall
  HP41cv expiriences of a new user Wolfgang 28 3,028 02-13-2013, 08:02 PM
Last Post: Mike Morrow
  A simple question about the HP41C or HP41CV Antoine M. Couëtte 6 1,137 12-16-2012, 04:06 AM
Last Post: Antoine M. Couëtte
  Problem with HP41CV Bruce Larrabee 19 2,241 09-18-2012, 09:29 AM
Last Post: Luiz C. Vieira (Brazil)
  HP41CV drains battery. Schematics? Harald 15 2,040 03-18-2012, 09:22 PM
Last Post: Luiz C. Vieira (Brazil)
  HP41CV batteries John Abbott (S. Africa) 3 742 03-02-2012, 06:15 AM
Last Post: John Abbott (S. Africa)
  HP41CV faulty Steve Hunt 6 996 12-27-2011, 12:45 AM
Last Post: Kerem Kapkin (Silicon Valley, CA)
  Repair HP41CV. Help needed. Kees van der Sanden 4 772 10-11-2011, 07:44 AM
Last Post: Ronald P

Forum Jump: