About HP-28S, a difference in black model and yellow model.


There is a kind that the kind that a shift key is yellow, and a shift key are black in HP-28S.
Is there a difference between even the part except for the color of the shift key and both?
How many kinds of HP-28S's are there?



I was not known about any HP28S with a blck shift key. That's new! Collectors piece?

Are the shifted labels (printed in the keyboard) in black too?

About the "regular" color: is it yellow or red (more to "wine", I'd say)? If I am not wrong, the 18C/19B/19BII are the ones with a yellow shift key. Is it correct?



I always thought that "red" is the only existing color scheme for the 28S shift-key; At least, I've never seen a yellow-shift key machine, not to mention a black-keyed one. Is there anything more to tell that discriminates the ordinary -- well, if an HP-calc can be "ordinary" at all ;-) -- "red-key-" from the "yellow-key machine"?


The HP-28S (and 28C) shift key is a rather dark purple.
I'd guess that the person who asked the question saw
a picture in which this key looks so dark as to seem
black - or saw an HP-28S under poor lighting and
thought the key was black.

The financial models of the same size and shape all
have a yellow shift key. Most likely the person who
asked did not realize that the model with a yellow
key was not an HP-28S.

Or was this an HP-28S with an incorrect key in it -
such errors do sometimes turn up on models where
individual keys are used, and not a single molded
unit comprising all the keys.

Wlodek Mier-Jedrzejowicz



it was 1985, I was about to become an Engineer, and I saw what I called an interesting trick: an HP11C with the HP15C's logo. If, at that time, I wondered how valuable collectro piece it was, I'd buy a new 11C and trade it. Now, I have no idea it it still exists or not.

If I understand it well, the shift key of any clamshell fits in any other. Based on my own experience, this is interesting to see. IF HEAT STAKES ARE UNTOUCHED, say, no one openned the machine and changed keys with a purpose, this is something to be collected.



I made a mistake in the mention.
The color of the shift key wasn't yellow, and it was dark red.
I saw HP-28S of the red shift key and a black shift key HP-28S.
HP-28S of the red shift key is sometimes seen even now.
But, my friend had HP-28S of the black shift key.
The key touch of the black shift key seemed to be unchanged with the red shift key, too.
I saw the secondhand model of black shift key sold in Japanese Akihabara once in another day.
It may be the model which is characteristic of Japan.

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