The Museum of HP Calculators

HP Forum Archive 21

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HP 45 versions
Message #1 Posted by james summers on 8 Apr 2012, 1:56 p.m.

Hi everyone

Can anyone help with the following queries:

When did the change to the direction of the storage arithmetic for STO - and STO / occur? (for example in early versions STO - resulted in x-R being placed in R whereas in later versions STO - resulted in R-x being placed in R)

When did HP stop using a metal strip above the power switch to avoid wear on the silver trim?

Was the timer code in all 45s or was it only present in the earlier versions? If the latter when was the change made?

Cheers

James

      
Re: HP 45 versions
Message #2 Posted by aurelio on 8 Apr 2012, 2:19 p.m.,
in response to message #1 by james summers

Hi james, this maybe can help

            
Re: HP 45 versions
Message #3 Posted by james summers on 8 Apr 2012, 2:38 p.m.,
in response to message #2 by aurelio

Thanks Aurelio, I missed that post when I was Googling earlier on trying to find some more info.

I will need to open ine to repair the battery contacts and that will give me a chance to have a closer look at the innards and compare them to those in the post you have highlighted.

Cheers

James

      
Re: HP 45 versions
Message #4 Posted by Michael de Estrada on 8 Apr 2012, 3:28 p.m.,
in response to message #1 by james summers

There are supposedly four versions of the HP 45 as follows:

Version 1 - Metal strip below display and front label says Hewlett Packard only.

Version 2 - Metal strip below display and front label says Hewlett Packard 45.

Version 3 - Painted silver strip instead of metal strip.

Version 4 - Painted OFF and ON legends replaced with raised molded unpainted OFF and ON legends and the serial number has been moved outside the battery compartment and located below the large label between the two bottom feet.

My earliest HP 45 is a Version 2 with S/N 1301A06579 and it does the x-R register arithmetic.

Edited: 8 Apr 2012, 3:33 p.m.

            
Re: HP 45 versions
Message #5 Posted by james summers on 8 Apr 2012, 3:56 p.m.,
in response to message #4 by Michael de Estrada

Hi Michael

Thanks for the info. Mine is later than your earliest one (s/n 1301A 09491) and doesn't have a metal strip (just black plastic with no sign of silver paint) but still has the x-R register arithmetic - which I only realised when working my way through the 45 manual on the Museum's DVD (which describes the later version of the register arithmetic) this afternoon and was getting different results which gave me a bit of a shock!

Cheers

James

                  
Re: HP 45 versions
Message #6 Posted by Michael de Estrada on 8 Apr 2012, 4:21 p.m.,
in response to message #5 by james summers

It sounds like yours may have had the metal strip at one time and that it was somehow removed, exposing the unpainted plastic housing below it.

                        
Re: HP 45 versions
Message #7 Posted by james summers on 8 Apr 2012, 4:35 p.m.,
in response to message #6 by Michael de Estrada

Yes, I had wondered about that, there is a thin groove along the bottom of the top edge of the strip which might have retained the metal strip.

            
Re: HP 45 versions
Message #8 Posted by Walter B on 8 Apr 2012, 5:07 p.m.,
in response to message #4 by Michael de Estrada

Hmmh, my earliest HP-45 shows S/N 1301A03077, metal strip, front label with 45, printed OFF/ON - and 7 STO1 3 STO-1 RCL1 results in -4, so it stores x-r. Looks like a mix of the versions you listed, doesn't it?

                  
Re: HP 45 versions
Message #9 Posted by Michael de Estrada on 8 Apr 2012, 5:42 p.m.,
in response to message #8 by Walter B

No. It sounds like you have a Version 2 just like mine.

                        
Re: HP 45 versions
Message #10 Posted by Walter B on 8 Apr 2012, 10:27 p.m.,
in response to message #9 by Michael de Estrada

Thanks - I should read better ;-/

            
Re: HP 45 versions
Message #11 Posted by Xavier A. (Brazil) on 9 Apr 2012, 9:57 a.m.,
in response to message #4 by Michael de Estrada

Hello Michael

Quote:
Version 4 - Painted OFF and ON legends replaced with raised molded unpainted OFF and ON legends and the serial number has been moved outside the battery compartment and located below the large label between the two bottom feet.
Mine (SN 1350A61713) has this 'raised molded unpainted OFF & ON legend', but the serial number is still inside the battery compartment - and I got the painted silver strip and hp-45 label.

What does it mean ?

                  
Re: HP 45 versions
Message #12 Posted by Jeff O. on 10 Apr 2012, 7:51 a.m.,
in response to message #11 by Xavier A. (Brazil)

My units with the raised, molded, unpainted ON & OFF legends (S/N 1350A81xxx & 1350A89xxx) also have the serial number sticker in the battery compartment. I was under the impression that the only “classic” units with the S/N sticker between the feet were very early HP-35's. The sticker which is between the feet provides the following information:

HEWLETT*PACKARD 
 3.75V       500mW
    MADE IN USA
Michael, do you possess or have you seen more than one example with the serial number sticker between the feet? The S/N sticker appears to be the same size as the above, so is it possible that your S/N sticker was transplanted there?
                        
Re: HP 45 versions
Message #13 Posted by Michael de Estrada on 10 Apr 2012, 9:40 a.m.,
in response to message #12 by Jeff O.

Hi Jeff,

I also have an HP 65 with the S/N located on the outside of the case between the lower feet. In both cases the date code prefix is higher than my other calcs of the same series. The prefix on my HP 45 V4 is 1507, .vs. your and Xavier's 1350, which suggests a much later manufacturing date, so perhaps this change was made during the time that the V4 was in production.

Michael

Edited: 10 Apr 2012, 9:43 a.m.

                              
Re: HP 45 versions
Message #14 Posted by Jeff O. on 10 Apr 2012, 10:47 a.m.,
in response to message #13 by Michael de Estrada

Michael,
That's interesting. I was wondering if there were any date codes beyond 1350. It seemed there must be, as the 45 was not officially discontinued until 1976 according to "A Guide to HP Handheld Calculators and Computers" by W. A. C. Mier-Jedrzejowicz. I wish the museum’s list of serial numbers included latest in addition to earliest. In any case, this means there are now at least five physical versions of the 45:

Version 1 - Metal strip below display and front label says Hewlett Packard only.

Version 2 - Metal strip below display and front label says Hewlett Packard 45.

Version 3 - Painted silver strip instead of metal strip.

Version 4 - Painted OFF and ON legends replaced with raised molded unpainted OFF and ON legends and the serial number still in the battery compartment.

Version 5 - raised molded unpainted OFF and ON legends and the serial number has been moved outside the battery compartment and located below the large label between the two bottom feet.

There may be more, depending on when the switch between the two versions of STO arithmetic occurred.

I just pulled out a rather gnarly HP-65 that I have in my desk (gnarly because it appears to have been forcibly removed from a security cradle), and sure enough, the S/N (1512A) sticker is between the feet.

...

      
Re: HP 45 versions
Message #15 Posted by Matt Agajanian on 9 Apr 2012, 8:06 p.m.,
in response to message #1 by james summers

Hello all. James, thanks for the 'heads up.' When I got my HP-45 a few days ago, I tested the Recall Arithmetic and yes, it works in the HP-15C order. I didn't think to verify the Storage Arithmetic order. I just checked it and it seems that my 45 works in reverse. In other word, if R3 contains 5, 6 RCL / 3 yields 1.2 in the display. Identically, 6 STO / 3, places 1.2 in R3.

I wonder if this order was different in other variations of the 45.

            
Re: HP 45 versions
Message #16 Posted by james summers on 11 Apr 2012, 2:16 a.m.,
in response to message #15 by Matt Agajanian

Hi Matt

Your order is the same as my early 45. In later models the storage arithmetic for minus and divide is reversed, ie in your example after 6 STO / 3 R3 in a later 45 would contain 0.83 (ie 5/6).

The cuveesoft.ch HP 45 emulator which I have on my iPad follows the later order.

Cheers

James

                  
Re: HP 45 versions
Message #17 Posted by Matt Agajanian on 13 Apr 2012, 4:29 p.m.,
in response to message #16 by james summers

I'm certain though, each variation does have its benefits. But, being that I don't need to go through mental gymnastics when I switch between Classics, V'Gers (yes, Voyagers but, hey I'm a Trekkie and my first thought goes to ST:TMP and the V'Ger probe) and Pioneers, this makes using my HPs a lot more consistent (and relaxing).

Edited: 13 Apr 2012, 4:32 p.m.

                        
Re: HP 45 versions
Message #18 Posted by Massimo Gnerucci (Italy) on 13 Apr 2012, 9:52 p.m.,
in response to message #17 by Matt Agajanian

Quote:
(yes, Voyagers but, hey I'm a Trekkie and my first thought goes to ST:TMP and the V'Ger probe)

Unfortunately V'Ger is taken as a codename for the 49G...

Massimo

                  
Re: HP 45 versions
Message #19 Posted by Eric Smith on 14 Apr 2012, 2:36 a.m.,
in response to message #16 by james summers

If you look at the actual firmware of the calculator, it turns out that storage arithmetic for addition and multiplication is reversed also.

Normally that doesn't matter, but it turns out that HP's calculator hardware and firmware are such that addition and multiplication of non-normalized numbers can be non-commutative. Of course, the firmware of the 45 is designed to prevent the user from ever having any non-normalized numbers, but it is possible to get them when transitioning from the undocumented timer mode back to the normal mode.


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