my high school got one in 1971 and through the punch cards, you could get to binary &,
|, and shift commands as well as program jumps. I have a complete one in a box with
reader, manuals, unused punch cards, etc. It was an eBay nostalgia buy a few years ago.
One of these days, I will be organized enough to have it on a table to play with it. It
was always fun to see the flashing nixie tubes as it ran calculations.
As to the tech inside, I would expect that it was a multi-LSI "big" chip
dedicated calculator design, so any memory was probably implemented as registers in the
chips. JUst a gues anyway.
best regards, Steve Thatcher
-----Original Message-----
From: Brian Knittel <brian at quarterbyte.com>
Sent: Feb 28, 2008 10:58 PM
To: cctalk at
classiccmp.org
Subject: Re: Monroe Programmable Electronic Calculator
Ooooh! That's really cool. My high school had one of
these around 1975 or 1976, we used it before we talked them
into buying an Altair. The punch card unit was pretty spiffy,
I think it used 8 of the row bits? And IIRC there were
instructions you could punch that were not available from
the keyboard. The cards were the votamatic type: hanging
chad and all. It was a lot of fun to program, and pretty
interesting and complex for a calculator.
I'd love to know what the memory technology was inside
-- acoustic delay, static RAM, or what?