Questions, questions

From: Gary Oliver <go_at_ao.com>
Date: Thu May 21 18:23:24 1998

I have one of the Heath 'Aircraft Navigation Computers' Tony
writes about. Bought it new (built it myself!) way back when
I was trying to be a student pilot - alas never finished the
pilot thing but did enjoy the calculator. I would have loved
to know the code, since the beast did all sorts of "foreground
background" sorts of things. The "multiprocess" nature of the
beast clearly showed through the user interface. Pretty advanced,
really.

I ultimately retired the unit (still works the last time I checked)
after I obtained the HP cartridge for the 41C. In fact, I believe the
Heath may have been on HP's mind when they designed their cart, as
one consultant working on the project borrowed my Heath calculator
for a while when they were in their design phase.

Big drawback of the Heath unit was it's life on battery power.
Sucked the nicads dry in about 1.5 hours of operation. Ran a little
longer in "standby" with the clock updated and other realtime
counters running, but no DISPLAY active. The HP ran DAYS on a set
of N cells.

Until now, I hadn't even considered it part of my "computer"
collection. I have several old calculators, but don't consider
myself quite a "collector" of those, (yet...)

Gary

At 07:39 PM 5/21/98 +0100, you wrote:
... snip
>
>Sort-of on-topic....
>
>A few months back (end of last year) I wandered past an electrical shop
>that had a large pile of Heathkit manuals for \pounds 2.00 each (about
>the cost of a magazine here, to give some idea). I ignored the
>loudspeaker system ones (of no interest) and a few of the others, but I
>bought a large pile of them - mostly amateur radio and test equipment.
>Some of them were from the old UK Heathkits (Heath of Gloucester,
>Daystrom or something like that).
>
>Anyway, amongst them was the manual for an 'Aircraft Navigation
>Computer'. It's a special-purpose RPN scientific calculator with
>functions to input up to 10 legs of a flight, fuel usage, wind direction,
>etc. It calculates the direction to fly in, etc. It's got all the normal
>scientific functions as well.
>
>It looked a little HP-like - keylayout and case were similar, and it had
>that 3-pin charger connector with the spring contact to short the outer 2
>pins when the charger was unplugged.
>
>Inside were _3_ 3870 microcontrollers (no idea as to the code, of course)
>and a RAM chip.
>
>Needless to say I'd love the device. The manual is interesting on its
>own, but hte machine would be even better.
>
>-tony
>
Received on Thu May 21 1998 - 18:23:24 BST