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Symbols of Electronic Sensors / Transducers / Detectors
How the neon-filled glow lamps came to hold a special place in enthusiasts’ hearts
UPDATE 18 JAN. 2024: The nostalgic desire to experience the mid-twentieth-century aesthetic provided by the glow and design language of Nixie tubes has still not gone away. But this niche demand has not been nearly great enough to keep them in production. And now, the last backstock versions of true Nixie tubes, produced in the Soviet Union and Eastern Europe in the 1980s, are at the end of their lifespans. At this point, anyone seeking that old-school glow can find it only in lookalikes made from more contemporary display technologies, like OLEDs that run on much lower voltages and whose manufacturing processes are much less labor intensive. //
Original article from 25 June 2018 follows:
On a cold December morning in the Czech village of Březolupy, a man stops his truck in front of a 17th-century castle. He puts on some heavy gloves, steps out of the truck, and opens the back hatch. Carefully, almost lovingly, he unloads crate after crate of heavy equipment and supplies—an industrial glass lathe, a turbomolecular vacuum pump, and glass. Lots and lots of glass.
The man is Dalibor Farny. In 2012, Farny began working to revive the manufacture of a display technology called the Nixie tube, the last commercial examples of which were produced when he was still a child.
These neon-filled glow lamps were ubiquitous in the late 1950s and 1960s, illuminating numbers, letters, and symbols in scientific and industrial instrumentation. Born in the basement of a German-American tinkerer in the 1930s and later commercialized by the business equipment maker Burroughs Corp., Nixies displayed data vital to NASA’s landing on the moon, lit up critical metrics for controlling nuclear power plants, and indicated the rise and fall of share prices on Wall Street stock exchanges, among thousands of uses. For many people, the warm glow of the Nixie came to evoke an era of unprecedented scientific and engineering achievement, of exciting and tangible discoveries, and of seemingly limitless progress. Remarkably, it continues to do so, even for people who, like Farny, grew up long after the tubes had faded from common use.
The picture shows my home-built digital clock, using Nixie tubes for readout. In contrast to most other nixie clocks being built these days, this clock does not use any transistor or IC for controlling and driving the tubes. Instead, the driving logic is built from trigger tubes, together with resistors, capacitors and silicon diodes. A video is on youtube.
This project is a followup to a similar clock I built between 2002 and 2007, documented on its own page. That clock used regular NE-2 style neon lamps as logic elements. Unfortunately, after a while, as these lamps aged, the clock became unreliable and unusable.
The new clock uses trigger tubes, of the МТХ-90 type (that's in Cyrillic characters; transliterated to Latin script it's MTH-90), which are widely available as "new old stock" on Ebay. Trigger tubes are essentially regular neon lamps with an extra "trigger" electrode, which can be used to ignite them. However, in this circuit I don't use the trigger electrode.
The above shows my home-built digital clock. It uses Nixie-tubes for readout. In contrast to most other nixie-clocks being built these days, my clock does not use any transistor or IC for driving the tubes. Instead, the driving logic is built from neon lamps, together with resistors, capacitors and silicon diodes.
The project started in 2002, when our university library was selling old outdated or otherwise superfluous books, and I very cheaply bought the book "Electronic Counting Circuits" by J.B. Dance, published in 1967, and apparently only ever lent three times by our library, all in 1973. It described how neon lamps can be used as logic elements in a ring counter, exploiting the fact that they need a higher voltage to ignite (the striking voltage) than to stay lit (the maintaining voltage):
Cross reference between NEMA and IEC schematic diagram symbols
The era of mainframe computers and directly programming machines with switches is long past, but plenty of us look back on that era with a certain nostalgia. Getting that close to the hardware and knowing precisely what’s going on is becoming a little bit of a lost art. That’s why [Phil] took it upon himself to build this homage to the mainframe computer of the 70s, which all but disappeared when PCs and microcontrollers took over the scene decades ago.
The machine, known as PlasMa, is not a recreation of any specific computer but instead looks to recreate the feel of computers of this era in a more manageable size.
Wednesday 19th June 2013 20:24 GMT
bscottm
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Re: It just costs money
It's not the GHz clock cycle that is the problem. It's the smaller feature size of the transistors that increases the single event upset (SEU) rate. Yes, the two are inter-related, but one could conceivably build multi-core, chip symmetric multiprocessors based on the PDP-11 at today's feature sizes and not have GHz clock cycle times (and still end up with significant SEU rates.)
A couple of years ago, a NASA/JPL scientist pointed out that the alpha particles (helium nuclei) from lead solder were causing interesting issues with current x86_64 I/O pins -- radiation issues on commodity hardware.
Convert an old computer ATX power supply into a highly capable workbench power supply. A perfect project for the budding experimenter with no spare cash for test equipment.