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HP-21S - Is it a rarity?
09-13-2014, 12:26 PM
Post: #3
RE: HP-21S - Is it a rarity?
the HP-21S and HP20S were almost identical, differing only in a very few of the functions offered. while the 20S was leaning slightly towards science, the 21S leaned slightly towards statistics. having said this, the lean either was was pretty minor.

the 20S (i have three) was a good 'workhorse' calculator, non-RPN, with 100 steps of program memory. these calculators (20S and 21S) competed well as a standard scientific against the likes of the casio FX-82, with the bonus of an absolutely excellent keyboard and display, rugged (welded) construction, and battery life (with 3x silver oxide SR44) approaching that of the HP-15C.

i suspect the value of a 20S and 21S are about the same, and the likely buyer is someone who wants to use the calculator, as opposed to a collector. i swapped my first 20S for a red-dot 35, and the next two i bought cheap on trademe for around nz$20. i'd say that if someone wanted one to use as a calculator, the one you've seen for 43 euros is about the 'right price'.

rob :-)
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Messages In This Thread
HP-21S - Is it a rarity? - jebem - 09-13-2014, 09:35 AM
RE: HP-21S - Is it a rarity? - Tim Wessman - 09-14-2014, 08:19 PM
RE: HP-21S - Is it a rarity? - robert rozee - 09-13-2014 12:26 PM
RE: HP-21S - Is it a rarity? - JuanJ - 09-13-2014, 01:33 PM
RE: HP-21S - Is it a rarity? - jebem - 09-13-2014, 02:06 PM
RE: HP-21S - Is it a rarity? - Gerald H - 09-13-2014, 02:28 PM
RE: HP-21S - Is it a rarity? - jebem - 09-13-2014, 03:16 PM
RE: HP-21S - Is it a rarity? - jebem - 09-13-2014, 08:13 PM
RE: HP-21S - Is it a rarity? - jebem - 09-13-2014, 07:30 PM
RE: HP-21S - Is it a rarity? - jebem - 09-13-2014, 08:25 PM
RE: HP-21S - Is it a rarity? - jebem - 09-13-2014, 09:09 PM
RE: HP-21S - Is it a rarity? - John R - 09-14-2014, 04:13 PM
RE: HP-21S - Is it a rarity? - John R - 09-14-2014, 04:00 PM
RE: HP-21S - Is it a rarity? - JimP - 09-18-2014, 04:19 AM
RE: HP-21S - Is it a rarity? - Paul Dale - 09-15-2014, 09:08 AM
RE: HP-21S - Is it a rarity? - rprosperi - 09-15-2014, 06:01 PM
RE: HP-21S - Is it a rarity? - walter b - 09-15-2014, 07:35 PM
RE: HP-21S - Is it a rarity? - jebem - 10-03-2014, 05:27 PM



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