RPN for Kids and Poor Guys

The famous HP-35 was neither the calculator for kids nor the choice of poor guys.

And now look at these two RPN calculators introduced in 1975:

The Unitrex 90SC assembled in Hong Kong and not really a high-quality product.

The WhizKid Edition of the National Semiconductor Model 600 obviously named with kids in mind.

Well, times changed!

Have a great weekend,



The Whiz Kid does it even without an ENTER key - must be either witchcraft or a bit too poor ;)

(Well, I know you can start with a cleared calculator and use + to terminate the first number entry. If that little wizard comes to a point where it needs a single parenthesis, however, the end is near ... ;)


The Unitrex 90SC was my FIRST "Scientific" calculator, long before I could afford any of the HP line.

Considered it a vast upgrade from my K& E Slide Rule in 1976.

I have stuck with RPN in one form or another ever since.

My technical and economic migration took me through:

- National Semiconductor Mathemetician



- HP.35 (Traded HP.25 for it; liked classy case design)

- HP.67 (UNIVAC on a Stick and IN YOUR POCKET! - Still have
that beast)

And a small but growing collection of Classics today.

Thanks so much for the memory refresh.

Sure is amazing how things have changed today.

Cheers to all..

John Stark

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