The Museum of HP Calculators

HP Forum Archive 16

[ Return to Index | Top of Index ]

HP-41C with gold bearings
Message #1 Posted by Pat on 19 Nov 2006, 8:20 a.m.

Hi, I have a fullnut HP-41C with gold bearings. I guess they were used for a power adapter that was never built. How rare are these model HP-41C's?

      
Re: HP-41C with gold bearings
Message #2 Posted by Randy on 19 Nov 2006, 8:26 a.m.,
in response to message #1 by Pat

The phrase dead common comes to mind...

            
Re: HP-41C with gold bearings
Message #3 Posted by Frank Wales on 19 Nov 2006, 12:51 p.m.,
in response to message #2 by Randy

I might be mis-remembering, but I think the gold balls persisted until HP decided to scrub the external PSU and went with the rechargeable battery pack instead (HP-82120A, a.k.a. Hurricane).

So, I'd be surprised to see them on any units made after the pack went into production, since HP knew by then they wouldn't be doing an external supply.

According to Craig Finseth's list, Hurricane was introduced just eight months after the 41C (which is earlier than I remember it, but since I think I'm the source of this date, I'm happy to trust it :-) ).

Consequently, I think that Randy's characterization of "dead common" is probably optimistic, and my own sense is that they're uncommon, but not rare (if you see what I mean); a bit like 41Cs themselves, compared with all HP-41s. But I don't have enough 41C's lying around to do a survey, so I could be mistaken about this.

Certainly, I wouldn't expect to see gold balls on any other HP-41 model, though, and that would make me suspicious about the machine's provenance if I found one.

                  
Re: HP-41C with gold bearings
Message #4 Posted by Randy on 19 Nov 2006, 3:31 p.m.,
in response to message #3 by Frank Wales

Frank,

I think you're right, I did overstate things a bit. But, from my perspective of whether or not 41's with gold ball power ports are "rare" (as in adding to the units value), I can't remember a time where collectors specifically labeled that "feature" as a variation to collect. Considering the fact you can move the parts from one case to another, it's pretty hard to prove one way or another it was original.

Now, if I could only find a "real" 41C halfnut... I've got a set of springs and gold balls to install ;^)

Edited: 20 Nov 2006, 11:23 a.m. after one or more responses were posted

                        
Re: HP-41C with gold bearings
Message #5 Posted by Vieira, Luiz C. (Brazil) on 19 Nov 2006, 4:23 p.m.,
in response to message #4 by Randy

Hi Randy, guys;

I had the chance to save four complete sets of such golden balls + springs + rubber retainer, and I use them now in three fullnuts: two CV's and one CX (I keep one set as spare...). The halfnuts' mainboard do not have the contacts for these power supply alternatives, although their case is the same and has the holes to install them. I also remember a warning that, because teh circuitry is directly connected to these lines, if, for some reason, the polarity is reversed when powering the calculator this way, the circuits will be unprotected. So, you do the math...

My 2¢.

Luiz (Brazil)

Edited: 19 Nov 2006, 4:42 p.m.

                        
Re: HP-41C with gold bearings
Message #6 Posted by David Smith on 20 Nov 2006, 10:51 a.m.,
in response to message #4 by Randy

Quote:
Now, if I could only find a "real" 41C halfnut... I've got a set of springs and gold balls to install ;^)

I have an honest to Bill and Dave genuine real 41C halfnut. And some springs and gold balls. Also a 41CV with silver label and trim.

                              
Re: HP-41C with gold bearings
Message #7 Posted by Randy on 20 Nov 2006, 11:32 a.m.,
in response to message #6 by David Smith

David,

Was the "HP Hewlett-Packard 41CV" model label on the front in silver as well?

                                    
Re: HP-41C with gold bearings
Message #8 Posted by David Smith on 21 Nov 2006, 11:00 a.m.,
in response to message #7 by Randy

Quote:
David,

Was the "HP Hewlett-Packard 41CV" model label on the front in silver as well?

Yes. All trim was proper matching silver.

                                    
Re: HP-41C with gold bearings
Message #9 Posted by David Smith on 21 Nov 2006, 11:14 p.m.,
in response to message #7 by Randy

A couple of other HP41 oddities: A couple of semi-blanknuts. One has labeled function keys, but blank keyboard background. The other has blank function keys, but standard keyboard background.

                        
Re: HP-41C with gold bearings
Message #10 Posted by Tony Duell on 22 Nov 2006, 2:40 p.m.,
in response to message #4 by Randy

Quote:
Now, if I could only find a "real" 41C halfnut... I've got a set of springs and gold balls to install ;^)

You'll be disappointed. AFAIK none of the halfnut PCBs have the pads that make contact with the top end of the springs -- I think all halfnuts are built on the same PCB with the difference being in the display/memory hybrid and the presence of the daughterboard on the CX.

On the other hand, all the fullnut keyboard PCBs that I've seen do have the pads.

      
Re: HP-41C with gold bearings
Message #11 Posted by Raymond Del Tondo on 22 Nov 2006, 1:32 p.m.,
in response to message #1 by Pat

Hi,

actually there exists a power supply for use with the gold balls.
It was made by a Company called 'Corvallis Team',
which was located in Germany;-)

The special thing with this power supply was the slide-in connector, of course.

HTH

Raymond

[ Return to Index | Top of Index ]

Go back to the main exhibit hall