HP-21S modified? - Printable Version

HP-21S modified? - Printable Version

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HP-21S modified? - PANAMATIK - 11-15-2016 09:32 PM

I saw this image of an HP-21S battery compartment and wonder, whether the visible printed circuit board inside is original? Does anybody know what kind of modification it could be? Should I keep my hands off?

[attachment=4147]

Bernhard

RE: HP-21S modified? - Maximilian Hohmann - 11-15-2016 09:45 PM

(11-15-2016 09:32 PM)PANAMATIK Wrote: ... and wonder, whether the visible printed circuit board inside is original?

Yes, just checked.

Greetings
Max

RE: HP-21S modified? - PANAMATIK - 11-15-2016 09:53 PM

(11-15-2016 09:45 PM)Maximilian Hohmann Wrote:
(11-15-2016 09:32 PM)PANAMATIK Wrote: ... and wonder, whether the visible printed circuit board inside is original?

Yes, just checked.

Greetings
Max

Oh, thank you. I just checked it myself with my HP-32S. You are right. Could have done that before posting here!

Bernhard

RE: HP-21S modified? - jebem - 11-16-2016 01:16 PM

Hi,

I was curious about the PCB variants on some of my Pioneer specimens.
Here it are:

HP-20S 3404S:

HP-21S 2939A:

HP-32SII 3525S:

HP-42S 3219S:
What about that strange looking object underneath the back cover and over the pcb metal plate?
It looks like a 4-pin connector to me.
I never noticed it there, but as I never opened a 42s I really can't tell.
Anyone?

RE: HP-21S modified? - Maximilian Hohmann - 11-16-2016 04:29 PM

(11-16-2016 01:16 PM)jebem Wrote: Anyone?

That's just the piece of plastic where the latch (so to say) of the battery cover engages. You can guess how it works from this picture (not mine, the HP42S is a white spot on my landscape to this day, but from the internet):

http://flickrhivemind.net/blackmagic.cgi?id=4034000937&url=http%3A%2F%2Fflickrhivemind.net%2FTags%2Fhp42s%3Fsearch_type%3DTags%3Btextinput%3Dhp42s%3Bphoto_type%3D250%3Bmethod%3DGET%3Bnoform%3Dt%3Bsort%3DInterestingness%23pic4034000937&user=&flickrurl=http://www.flickr.com/photos/43851301@N02/4034000937

RE: HP-21S modified? - jebem - 11-16-2016 05:28 PM

(11-16-2016 04:29 PM)Maximilian Hohmann Wrote:
(11-16-2016 01:16 PM)jebem Wrote: Anyone?

That's just the piece of plastic where the latch (so to say) of the battery cover engages. You can guess how it works from this picture (not mine, the HP42S is a white spot on my landscape to this day, but from the internet):

http://flickrhivemind.net/blackmagic.cgi?id=4034000937&url=http%3A%2F%2Fflickrhivemind.net%2FTags%2Fhp42s%3Fsearch_type%3DTags%3Btextinput%3Dhp42s%3Bphoto_type%3D250%3Bmethod%3DGET%3Bnoform%3Dt%3Bsort%3DInterestingness%23pic4034000937&user=&flickrurl=http://www.flickr.com/photos/43851301@N02/4034000937

Thanks, Maximilian.

Silly me. On a closer inspection under stronger light, I can see now those 4 plastic triangles to latch the battery cover on all of these calculators. What have fooled me was the bright reflection on the metal plate that is not visible on the other models.

I really need to do deeper inspection before posting here Sad

RE: HP-21S modified? - ElectroDuende - 11-20-2016 08:27 PM

(11-16-2016 01:16 PM)jebem Wrote: HP-42S 3219S:
What about that strange looking object underneath the back cover and over the pcb metal plate?
It looks like a 4-pin connector to me.
I never noticed it there, but as I never opened a 42s I really can't tell.
Anyone?

That's where the SIM card goes.

;-)

RE: HP-21S modified? - Christoph Giesselink - 11-21-2016 07:23 PM

(11-15-2016 09:32 PM)PANAMATIK Wrote: I saw this image of an HP-21S battery compartment and wonder, whether the visible printed circuit board inside is original? Does anybody know what kind of modification it could be? Should I keep my hands off?

Bernhard

There are pictures of a HP20S and a HP10B PCB available at:

http://www.hpmuseum.org/cgi-sys/cgiwrap/hpmuseum/archv021.cgi?read=236226#236226