30 Mar
2007
30 Mar
'07
8:53 a.m.
it was the 1967 issue of Electronics Illustrated that was sold on eBay (not
Radio-Electronics)
http://www.nzeldes.com/HOC/DialComp.htm
To which Mike replied...
> Take a look at item #270101277189 on Ebay, in the completed section. Is
> that it?
30 Mar
30 Mar
10:23 a.m.
On 30 Mar 2007 at 0:00, Steve Thatcher wrote:
it was the 1967 issue of Electronics Illustrated that
was sold on eBay (not Radio-Electronics)
I remember reading that article when it came out. I recall the neon-
bulb ring counters--they looked like a nightmare to get right and
something that would eventually require more tweaking as the bulbs
aged.
There were other "computers" that made their showing at science
fairs. One was a tic-tac-toe playing design that, IIRC, used Stroger
switches (something that might have also worked for the calculator
shown in the magazine article).
Around the same time, I also seem to recall a "morse code typewriter"
design, complete with a keyboard fabricated from individual switches.
It may have been in Radio-Electronics. Anyone remember it?
Cheers,
Chuck
10:58 a.m.
On 3/30/07, Chuck Guzis <cclist at sydex.com> wrote:
On 30 Mar 2007 at 0:00, Steve Thatcher wrote:
It would be sensitive to the light in the room, wouldn't it? ISTR
there was some note somewhere about the avalanche voltage on a neon
bulb being affected by swings in ambient light, but as this stuff is s
bit before my era, I could easily be wrong.
-ethan
it was the 1967 issue of Electronics Illustrated
that was sold on eBay (not Radio-Electronics)
I remember reading that article when it came out. I recall the neon-
bulb ring counters--they looked like a nightmare to get right and
something that would eventually require more tweaking as the bulbs
aged. 
1:13 p.m.
On Fri, 30 Mar 2007, Ethan Dicks wrote:
It would be sensitive to the light in the room,
wouldn't it? ISTR
there was some note somewhere about the avalanche voltage on a neon
bulb being affected by swings in ambient light, but as this stuff is s
bit before my era, I could easily be wrong.
There's a document on this site that talks about the "Dark Effect"in
glow lamps:
http://www.donsbulbs.com/bulbs/g/l/ge1965glowlamp/005.gif
It's part of a GE publication, the whole of which is on that site:
http://www.donsbulbs.com/cgi-bin/r/t.pl/library1965geglowlamps.html
Mike Loewen mloewen at cpumagic.scol.pa.us
Old Technology http://sturgeon.css.psu.edu/~mloewen/Oldtech/
1:47 p.m.
On 30 Mar 2007 at 13:58, Ethan Dicks wrote:
It would be sensitive to the light in the room,
wouldn't it? ISTR
there was some note somewhere about the avalanche voltage on a neon
bulb being affected by swings in ambient light, but as this stuff is s
bit before my era, I could easily be wrong.
Some neons had a bit of something included in the glass to provide a
bit of ionizing radiation to render the bulb less sensitive to
ambient light. I don't think that NE2's are the best gas diodes for
digital uses--there are (or used to be) higher-quality neons that
have more uniform characteristics.
I remember that the pedalboard on old (tube-type) Lowery organs used
neons in some capacity--I think it was to quash the "sustain" when a
note was played that overlapped the sustain of the previous note.
I've got an old neon "nightlight" in my shop that's aged sufficiently
that it comes on whenever I turn on the overhead illumination but
otherwise doesn't glow when the light level is low.
I wonder if the neon ring counter circuit might be replicated using
something like diacs or tunnel diodes for the active device. Of
course, you'd need an LED or something to actually show the logic
state.
Cheers,
Chuck
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cclist＠sydex.com -
ethan.dicks＠gmail.com -
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mloewen＠cpumagic.scol.pa.us