OH-HP 30S overhead projector calculator

[mfleming]

I was recently the sole bidder on what is labeled "The Educator, OH-HP 30S Scientific Calculator" in NIB condition. See attached picture. It's a product of Stokes Publishing Company, Sunnyvale, CA (California, not Canada!) Both the display and keyboard are transparent, with the center of the calculator body holding a battery and calculator electronics (the unit is labeled "Emulates Hewlett Packard HP 30S" so perhaps there's a micro in there?). The unit only shows a few digit pixels and an annunciator when turned on, so it is not functional.

I was aware other calculator companies produced overhead versions of their calculators for classroom use, in fact I picked up one for the Casio fx-7000 a few years ago. That's a fairly capable scientific calculator.

Does anyone know of other HP calculator overhead models, or similar scientific calculators for overhead projectors from other manufacturers? These appear occasionally on TAS, but at prices that suggest very little interest from buyers.

~Mark