by Wlodek Mier-Jedrzejowicz Ph.D.
|Introduced on May 1 1976, this was the
eleventh small electronic calculator sold by HP and the
fourth member of the Woodstock family. It was not
programmable but provided a wide range of business,
scientific and statistical functions. (In fact the
nearest model to its concept since then has been the
One way to distinguish it from the HP-25 is to see that its two shift keys are gold and black, not gold and blue. To distinguish it from the HP-22, you can note that the standard business functions n i PMT PV FV are gold-shifted functions on the second row of keys.
The statistics include computation of variance and normal distribution parameters in addition to the usual functions. It was only the second handheld, after the HP-45, to provide recall arithmetic. (See the separate article about this.)
This was an ideal model
for anyone who did not need programmability - business
users who sometimes needed technical functions and
technical users who wanted to do business calculations,
and the HP-27 apparently cut into sales of the HP-22. Its
codename "Salad" seems to acknowledge
that it was a mixture of various good things!
This article is part of the WMJARTS file. This file contains a series of articles written by Wlodek Mier-Jedrzejowicz and published in DATAFILE, the journal of the HPCC. The article was reproduced with permission of the author.
Copyright © Wlodek Mier-Jedrzejowicz Ph.D.