Hi guys,
Since Friedhelm build his Nixie clock with tube electronics in 2005:
https://www.jogis-roehrenbude.de/Leserbriefe/Bruegmann-Digital-Roehren-Cloc…
I'm more or less trying to build a "tube" Nixie clock with neon lamps
and/or trigger tubes/thyratrons instead of vacuum triodes.
In 2005 I told Friedhelm that this is a nice clock..but build the wrong
way. To tube times one build dividers using monoflops and ring counters
with decatrons and so on..not with vacuum tube Flipflops.
We've calculated the energy costs for this tube clock of approx. 400
Deutschmarks in 2005, don't really want todo this today..especially for
the country with the dumbest and worst energy politics world wide..
green ideology politicans here has blown up the worlds best and safest
nuclear power plants to dust...
...
Since I've got approx 1000 of small chinese neon bulbs in the meantime,
I've tried to build Ring counters out of the neon lamps..it works, but
not that good, since the differnece between the Ignition voltage and the
Extinguishing voltage is to small on this tubes, the counters are
unreliable.
A few years ago some russian trigger tubes TX4b got available, that are
small pencil tubes with only 3,5mA Ia max. Those tubes have a bad
reputation in rossia because they where put in to the vertical
deflection circuit of some soviet made black and white TV sets and it
was a bad design, the tubes where overloaded and don't lasted for very
long. Another type, the MTX-90 was more often suggested and used.
After some years the box with the TX4b fell into my hands and I'm
searches again in the russian Internet for possible uses of the TX4b in
Ring counters..the circuit design depends on the parameters of the tubes
and isn't really that simple. I've searched for examples and finally
found some morse transmitter device with "digital electronics" build out
of the TX4b tubes.. russians wrote that this thing was unreliable :-)
Nevertheless I found what I'm searching for, an schematic and a
description in russian, english and french.
..so I have an working ring counter here next to me on a breadboard. :-)
There is still an MPSA42 used as an pulse former in the clock circuit
that I want to change agains a trigger tube. I need an Ide of an circuit
that gets triggered on approx. 30-40V and outputs an rectangle pulse of
lets say 60V and 10-30µs duration to properly trigger the ring counter,
using possibly only one trigger tube.
I think no one knows that for now..but I'm very grateful for links
to older literature on this topic.
approximately in 2000 I'm parted out old hp tube counters, the displays
where "thermometer Displays using 10 pcs. of neon lamps, one for each
number. The counters used 4 12at7 type "digital" tubes (don't remember
the exact type for now) with biquinary output to the neon lamps.
Later hp counter modules used the very same schematics and the neons and
one hybrid photoresistor module in front of the neons as decoder to
drive nixie tubes. I've tried it already in the past with the neon bulb
ring counters.. a cheap photoresistor in a balc schrink tube that was
put onto the neon lamp can switch a nixie..it works flawlessly.
Tried this on the TX4b .. works too. :-)
..other schematics ad an additional trogger tube for each nixie
cathode..the effort pretty much explodes...
Hope someone can help with some hints or links.
Regards,
Holm
--
Technik Service u. Handel Tiffe, www.tsht.de, Holm Tiffe,
Goethestrasse 15, 09569 Oederan, USt-Id: DE253710583
info(a)tsht.de Tel +49 37292 709778 Mobil: 0172 8790 741
An acquaintenance of mine, in the BBS world, has a zero-cost dialup service
for anyone wishing to use it. Thought I'd spread the word.
For dialup details, follow the link. I believe he said there are ninety
nodes and may see five used at any given time.
Ref: https://2600.network
Enjoy,
Daniel
sysop | Air & Wave BBS
finger | calcmandan(a)bbs.erb.pw
> Paul Koning <paulkoning(a)comcast.net> wrote:
> On the other hand, the even more obscure DECnet/8 was found a couple
> of years ago. Its main limitation ....
Besides being Phase-I, DECnet/8 is not a "complete" implementation. The
only application provided is a console to console talk program that can only
talk to other PDP-8 nodes. There's no FAL, CTERM/RTERM, NFT, NCP, or any of
the other things you might expect. I think DEC expected customers to write
their own RTS/8 and DECnet-8 applications.
Bob
I learned tonight that someone cleaned out my storage unit, and part of their haul was a couple of cartons of DEC boards. I haven't dug up the itemized list but in there were several QBus VAX memory boards, a graphics adapter, a microVAX III board set, a couple of RQDX boards, both QBus and Unibus serial boards, Unibus SDI board sets, a BA123 cabinet, tk70 controllers, a couple of Ethernet boards...
And a Mentec/93.
If anyone unfamiliar approaches you about selling a big stash of DEC, please get all the info you can and call the police.
Thank you.
Doc
On Mon, 2 Mar 2026, Fred Cisin wrote:
> With a couple thousands I mean several thousands. And drawerS and
cabinetS
> because we got several cabinetS with drawerS with our machine. One
drawer
> contains three trays that hold about 2000 cards each.
> Download our files and count the card yourself!
Download from where?
As a student at UC Berkeley (1967-1971), I had a part-time job at the Computer Center, which ran a CDC 6400 under SCOPE. We punched cards, transferred them to magnetic tape, and used UPDATE to maintain logical decks. I personally used this technology while working on CAL SNOBOL and CAL TSS. Once we got CAL TSS far enough along to support development (on a second CDC 6400), we switched to Teletypes (a mixture of Model 33’s and Model 35’s). I still have source code for CAL SNOBOL because of archivists at U. of Arizona and U. of Texas, but most of the source code for CAL TSS was lost (listings survive).
Paul McJones
https://www.mcjones.org/CAL_SNOBOL/https://caltss.computerhistory.org/
Hello,
I bought a Wang 600 in unknown operating condition, but it looked to be
complete and undamaged. Unfortunately, the shipper used a "professional"
shipping service that wrapped this calculator in a single layer of bubble
wrap, put it in a single wall box, and filled the rest of the space with
packing peanuts. The result was predictable. The rear and sides of the
molded ABS case were completely shattered, the rear mounted fan was knocked
off, the housing bent, and a fan blade broken off. Fortunately (if that's
the right word) the chassis, cards, keyboard, and display all seem intact.
To try to assess the extent of the damage, I would like to complete the
removal of the plastic case but do not see how it is fastened to the
chassis. Can anyone help? Also, any troubleshooting info would be
appreciated! I already have the schematics, but I probably won't be needing
them until I do some inspections and basic checks.
Thanks,
Stan
So studying about 1960s operating systems recently, it occurred to me that
the ASR-33 wasn't really "a thing" until the late 1960s. Yes, they
technically existed since 1963, but even going through 1960s Datamation
issues - you don't see a lot of ads or mention of ASR-33 until 1965.
The IBM 1050 maybe existed in 1961 for the IBM 709, but even so - general
thought is that CTSS (operating system) was largely initially developed
using punch cards.
So - are there any archives or collections of these original punch cards?
Or are they essentially all gone/destroyed, since in general after some
code was "perfected" it was likely then archived to tape?
Anyway, apologies - it was just something that only recently occurred to
me, that basically all of the original operating systems originated on
punch cards: CTSS, Supervisor, AOSP, SCOPE, even MULTICs. So - do any of
those decks of cards still exist in archive? Would be neat to see a photo
of those - except it would be a shoebox of punch cards like any other, I
suppose.
Or is this wrong, and the top tier teams making these OS's, probably had
teletypes and all the magnetic tape they wanted?
-Steve
So back in the 1990's the dream server for me was an Everex system
called the Step/MP. Cube shaped, EISA bus, could take multiple 386/33
CPU blades and ran SCO. But all I had was memories as there was very
little info on the Net.
Today I was going through a closet I haven't been able to access for 20
years and in the Computerworld 1992 25'th anniversary issue I found it:
A 2 page monster ad about the Step/MP. $13k, could have six 486/33 CPUs,
EISA/ISA bus, 64mb of memory stock with support for 4mb SIMMs. So it did
exist....
Question is did any of them make it out there? SCO was the obvious OS,
but given that it was a SMP system I wonder if there was an NT 4.0 HAL
out there like there was for the NCR 3550/4300 series of multiprocessor
systems. Anyone have one? Seen one in the wild?
I am curious. Everex/STEP was always the best quality system for a
server, right alongside Compaq. Sad they went out of business.
Chris
All –
I’m working on a simulation project where I’m using two Codex 2121 LDSU (local data service unit) modems to simulate a leased line setup to a DECSYSTEM-2020. These modems use 2-pair cabling (TX+,TX-/RX+.RX-) and DCE DB25 connections. I believe each modem is working in loopback mode, but I can’t get it to work over the 2-pair interface between the modems (i.e., a loop back plug on one modem and terminal on the other). The only manual I’ve been able to locate is the sales brochure, not any kind of user manual.
Anyway, have the interface cross-connected (i.e., TX to RX) but there are no polarity markings so I just used each pair in the same color order.
Has anyone used this kind of modem before, have a manual, or know how to connect them? Thanks!
Rich
--
Rich Cini
http://cini.classiccmp.orghttps://github.com/RichCini
