25 May
2005
25 May
'05
11:23 p.m.
On Wed, 25 May 2005, Dwight K. Elvey wrote:
When building neon logic, it might be better to
consider
using capacitive coupling to connect up your logic.
Otherwise you may find that you'll have a significant
level shifting problem.
I think we've reinvented an old wheel that tends towards the
square. Abandoned for good reason!
Slightly changing subject (!), but remaining on discretely
constructed memory, one truly practical memory that was tried and
abandoned about 1952 (one of the Standards computers) was a
switched capacitor memory. It was umm revived some years later and
is now of course universal.
A discrete-capacitor, diode-switched, dynamically-refreshed memory
was built and tested and performed apparently well was built for
SWAC? SEAC? or something in 51, 52 [ref in Huskey's COMPUTER
HANDBOOK] but abandoned as solid-state diodes were prohibitively
expensive.
It would clearly be most straight-forward to build one today, even
with el cheapo ceramic disks. Probably could do .25 sq in per cell
on a PC board. And since one was actually made, it would be
historically correct.