Modified HP-28S seen on eBay


Here is an HP-28S that just sold on eBay.

Item #130080704876

It appears to have a 28-pin connector where the display should be and came with a matching ribbon cable!

Anybody have a clue what this might be used for?



Possibly some kind of overhead display conversion?

Another (perhaps a tad larger) matrix LCD without backing and see-throgh could be placed on a transparency projector for classroom display...

Bill Wiese

San Jose CA


I can be used as an example of people who tamper with calculators and can't put them back together!!!!

His response to queries about if the calculator works is sooooo lame!!!



I have one like these, mine has been made to test the keyboard during engineering (CPU-board missing). This one might have been used to test various different displays.

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