>
>Subject: Re: Neon bulb logic elements link?
> From: "Dwight K. Elvey" <dwight.elvey at amd.com>
> Date: Wed, 25 May 2005 16:05:54 -0700 (PDT)
> To: cctalk at classiccmp.org
>
>>From: "Eric Smith" <eric at brouhaha.com>
>>
>>I wrote:
>>> You turn on a particular tube by dropping the X line to 0V and raising
>>> the Y line to +105V. The selected tube sees 105V, while the other tubes
>>> in the same row and column see 97.5V.
>>
>>Tom wrote:
>>> I think your idea is generally right, but this detail seems wrong:
>>> when X goes from +7.5V to 0V, the entire line will see 105V,
>>> striking the entire line.
>>
>>Nope.
>>
>> 7.5V 0V
>>
>> X0 X1
>> | |
>> | |
>> 97.5V Y0 --------90V-----------97.5V
>> | |
>> | |
>>105.0V Y1 --------97.5V----------105V
>>
>>
>>Locations (0,0), (1,0), and (1,0) are all still below the strike
>>voltage.
>>
>
>Hi
> 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.
> Just a thought
>Dwight
>
The general design rules were pulse logic based so capacitive coupling
was the norm and diodes were not uncommon.
I've done simple binary counters and shift registers with NE2s and
it's fun and fairly tolerent. Somewhere I've seen a complete schematic
for a 3T (Tic Tac Toe) player that used Neon lamps and 2D21 thyratrons.
Allison
On May 24 2005, 17:11, James Fogg wrote:
> I seem to recall that neon's behave as diodes. I might be wrong.
No, neons happily pass AC. You must be thinking of something else.
--
Pete Peter Turnbull
Network Manager
University of York
Hello,
There was a link posted on this list in the last month that I can't find
now.
The site that had some scanned pages from a book, about using neon bulbs as
logic elements. I planned to read it later, and then lost it. Anyone seen
that site?
Thanks,
-Frank
>From: "Vintage Computer Festival" <vcf at siconic.com>
>
>On Wed, 25 May 2005, Kevin Handy wrote:
>
---snip---
>
>> The archive should be for our own use, not some theoretical idiot 2000
>> years from now trying to boot a Kaypro. He's probably going to have a
>> whole different set of problems with an archive than we could conceive;
>> like locating the "any" key.
>
>Right, so don't make the archives more complex than they need to be.
>
>--
>
>Sellam Ismail Vintage Computer Festival
Hi Kevin
I'm sure if you needed an archived image zipped before
you could use it and you requested it that way, Sellam
could provide it in that format for you ;) That doesn't
mean he must store it that way. Why it is only useable
in zipped form I don't really understand but if that
is what you NEED for your "own use", that is what you
can get. It doesn't restrict how Sellam stores the image.
It is hard to say what piece of information will be
of interest to someone 2000 years from now. It may
be a Kaypro that is being researched or it might just
be that they wanted to know what the typical storage
media size was.
If the information was zipped first, they'd need to
first recognize that it was zipped. They'd then need
to create a working unzipper before they could answer
either question. Finding an unzipped source might be
just as hard.
I use zipped files for my personal archive but then
I know who is going to look at it. I'd even expect to
send an image to Sellam as a zipped file. For the
purpose he has in mind, I'm sure he'd unzip it.
Dwight
its really driving up the price of stuff
unnecessarily.
--
This (dkdkk, ed sharpe, sassyscottie, et al.) has started to
really impact what I can get to scan. I have to carefully
consider if this is the only copy of a document I know of,
or if there are other sources that I might have access to
in the future.
It makes me feel really great to be giving this stuff away
too, after having paid through the nose for it (the latest
example being the IBM 1410 CE manual).
http://wps.com/archives/Burroughs/images/N101-5.jpg
OUCH! OK, assuming Nixies are more or less the same as other Ne
devices, they will make lousy memories.
* Ionization time is approxmately 50mS. Longer in the dark!
With keepalive currents etc "as low as 10 microseconds".
OK they're slow.
* electrode deterioration is via sputtering, not impurities.
Varies approx. as the 3rd-power of current.
Clearly, neons in HP counters are probably the traditional
constant bias generators. They were typically used in DC-coupled
amplifiers to provide plate-to-next-grid drop.
Neons also got used with CdS cells and the like to make 60Hz photo
choppers.
Unless someone has som ehard data on them being used "digitally"
I'd assume the HP counter use was simply as generic, non-switching
circuit elements.
A write-only neon memory would still make a nice addressable
display!
>From: "Tom Jennings" <tomj at wps.com>
>
>On Wed, 25 May 2005, Eric Smith wrote:
>
>>> sustain around 80V. [...] You could probably make a coincident-voltage
>>> memory from them... but they'd be slow I think, but pretty.
>>
>> Sounds like a fun project!
>>
>> Lessee... If the numbers are 80V and 100V...
>
>Actually, it might be easy enough to be fun. There aren't many
>storage method that are direct-readout of all cells! (It would
>make a display too).
>
Hi
Hp made a counter tube using several electrodes. The idea
was that there was only enough current to keep one electrode
at a time lit. It might be more practical to make a storage
element with multiple electrodes instead of depending on
matching several NE-2's.
Dwight
--- Barry Watzman <Watzman at neo.rr.com> wrote:
> You don't understand how E-Bay works. If you bid $5
> and I bid $100, I win
> the item .... for $6. And the fact that I had bid
> $100 is never even seen,
> by anyone.
I understand it quite well. I believe that both you
and Eric missed the point of my remark, which was
simply that there was in each case another individual
who was willing to pay essentially the same price at
which the auction closed, therefore there was a
market, however small, in which the exhorbitant
closing prices of those G-15 document auctions was in
fact the "correct" market price. You cannot blame an
individual willing to pay that price as driving up
prices -- it takes at least two bidders willing to pay
"above market" prices to do this. His only
alternative would have been to bid less, and lost.
The situation is different in an ordinary sale, where
the price will rise to whatever a single individual is
willing to pay, as long as the seller is willing to
hold out for a higher price.
--Bill
---snip---
>
>However popular a machine is now, there will come a time when there are
>none still running (and I suspect this will be true of modern PCs long
>before it's true of things like PDP11s, but I digress). I feel it's very
>unlikely that our archive of boot disks will survive and no copies of a
>now-common archive program specification will remain, though.
>
>-tony
>
Hi Tony
It is more that we can not predict what pieces of the puzzle
will be missing. If I'd have known when I was a kid that Mickey
Mouse watches were going to have value, I'd have bought several.
As you know, from personal correspondence, I'm working on a
machine that wasn't all that uncommon in Europe. Some things
for it just don't seem to exist ( programs and manuals ).
They were out there but they are gone now. I can't predict
what will be lost and what will survive. I can't predict
why one obscure piece of information continues to be available
despite its limited application while other bits of information
the were more popular are gone.
The Idea of an archive is to try to minimize the interdependencies.
The archive should include the zip, rar and tar information.
That doesn't mean that the archive should depend on them.
Dwight
a salvage area I visit weekly has some some stuff that may or may not be
of interest.
IBM-3900 printer (LARGE!)
3 IBM-3179 G terminals
sun stuff (normal)
pc, racks, etc.
Dallas TX
I don't want any of it. I can bid on it in complete sets often 3 pallets
full of stuff.
Any interest? email me directly with how much you'd like me to bid, as
well as how, and how soon, you will get it out of dallas.
http://rikers.org/gallery/hardware-20050525
I need to place any bids by tomorrow 10am CDT
--
Tim Riker - http://Rikers.org/ - TimR at Debian.org
Embedded Linux Technologist - http://eLinux.org/
BZFlag maintainer - http://BZFlag.org/ - for fun!
