Gee, I still have a similar Litton scientific calculator with vector CRT
 display (RPN calculator where you can see all 6 stack values at once).
(circa 1960?)
The CRT is refreshed using long wire magnetostrictive memory coiled up
in it's base. All registers are in this circulating magnetic stress
memory.
All germanium transistors too. Still works and is great conversation
piece
for techy visitors. And I still have a working PDP8E with teletype,
PDP11/20
PDP11/10, PDP11/45. Also a dismantled PDP8I (used to take up 4 rack
bays)
with a 32Kword DF32 disk drive.(Fixed heads, 3600RPM). Anyone remember
DECtape? Used it on a siesmic vessle since HD's couldn't take the
residual
shock from the blasting (strong enough to knock a cup of coffee 12"
up off the table top).

And of course the requisite Altair, IMSAI 8080, Sol 100, ZX80, etc.
My first memory stack for the IMSAI kit was litterally that. A stack of
2102's wired togther (except for DI/DO) and soldered directly to the
backplane (since I couldn't afford a 'real' memory card at the time).
Hand coded & loaded a program to toggle the IE pin (int enable since it
was a single instruction) to generate video (used the front panel output
port for the sync info). With only 1K of RAM I was only able to put up
about 10 very wide characters on the screen, but it was my first
non-trivial 'program'.

David VanHorn wrote:
>
> >Best I can probably manage these days is a ZX81 (ZX80?), a D2 kit an old
> >desktop calculator that uses core for storage and another that uses a wire
> >spiral and ultrasonics for its 10 or so memories.
>
> I had a couple of those! CRT display, all discrete transistors.
> Pretty amazing really.

Wasn't it... All serial ALU, all timing done with R/C. It's a wonder it
still works what with component aging and all.

R

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