neon

34 Articles

Neon Watch Glows Rather Nicely, Tells Time

January 17, 2024 by 12 Comments

It wasn’t long after the development of the LED that LED watches became available. They were prized for their clear light output and low power draw. Neon bulbs, on the other hand, are thirsty for current and often warm or even hot in operation. And yet, [Lucas] found a way to build them into a sweet watch that actually does the job. Nice, right?

The design uses a simple trick to avoid killing the batteries with excessive power draw. The neon lamps are only activated when the user waves a hand above the watch, at which point the lamps light to display the time. Reading the time is  a little fiddly, but understandable with the aid of this PDF diagram. Basically, the two electrodes of each neon lamp are driven independently. This gives each of the four lamps three possible states: with the first electrode lit, the second electrode lit, or both lit. Four lamps multiplied by three states equals 12—so the watch can display the hour quite easily. As for minutes, a similar scheme is used with some modifications for clarity. Setting the time is via a light sensor on the watch which picks up flashes from a computer screen.

It reminds us of a time when we once thought nixie tubes were too power hungry for a wristwatch build… until the hackers of the world proved us wrong. Video after the break.

Continue reading “Neon Watch Glows Rather Nicely, Tells Time” →

Noble Graphs: Displaying Data With Neon Like Its 1972

October 17, 2023 by 11 Comments

In the days before every piece of equipment was an internet-connected box with an OLED display, engineers had to be a bit more creative with how they chose to communicate information to the user. Indicator lights, analog meters, and even Nixie tubes are just a few of the many methods employed, and are still in use today. There are, however, some more obscure (and arguably way cooler) indicators that have been lost to time.

[Aart Schipper] unearthed one such device while rummaging around in his father’s shed: a pair of Burroughs Bar Graph Glow-Transfer Displays. These marvelous glowing rectangles each have two bars (think the left and right signals on an audio meter, which is incidentally what they were often used for), each with 201 neon segments. Why 201, you may ask? The first segment on each bar is always illuminated, acting as a “pilot light” of sorts. This leaves 200 controllable segments per channel. Each segment is used to “ignite” its neighboring segment, something the manufacturer refers to as the “Glow-Transfer Principle.” By clever use of a three-phase clock and some comparators, each bar is controlled by one analog signal, keeping the wire count reasonably low.

Don’t get us wrong, the warm, comforting glow of Nixie tubes will always have a special place in our hearts, but neon bar graphs are just hard to beat. The two do have a similar aesthetic though, so here’s hoping we see them used together in a project soon.

Thanks to [Jan] for the tip!

Retrotechtacular: Putting Pictures On The Wire In The 1930s

April 25, 2023 by 52 Comments

Remember fax machines? They used to be all the rage, and to be honest it was pretty cool to be able to send images back and forth over telephone lines. By the early 2000s, pretty much everyone had some kind of fax capability, whether thanks to a dedicated fax machine, a fax modem, or an all-in-one printer. But then along came the smartphone that allowed you to snap a picture of a document and send it by email or text, and along with the decrease in landline subscriptions, facsimile has pretty much become a technological dead end.

But long before fax machines became commonplace, there was a period during which sending images by wire was a very big deal indeed. So much so that General Motors produced “Spot News,” a short film to demonstrate how newspapers leveraged telephone technology to send photographs from the field. The film is very much of the “March of Progress” genre, and seems to be something that would have been included along with the newsreels and Looney Tunes between the double feature films. It shows a fictional newsroom in The Big City, where a cub reporter gets a hot tip about an airplane stunt about to be attempted out in the sticks. The editor doesn’t want to miss out on a scoop, so he sends a photographer and a reporter to the remote location to cover the stunt, along with a technology-packed photographic field car. Continue reading “Retrotechtacular: Putting Pictures On The Wire In The 1930s” →

Making Neon Trees The Easy Way With No Oven Pumps Required

April 20, 2023 by 26 Comments

Neon lamps are fun and beautiful things. Hackers do love anything that glows, after all. But producing them can be difficult, requiring specialized equipment like ovens and bombarders to fill them up with plasma. However, [kcakarevska] has found a way to make neon lamps while bypassing these difficulties.

[kcakarevska] used the technique to great effect on some neon tree sculptures.
The trick is using magnesium ribbon, which is readily available form a variety of suppliers. The ribbon is cut into small inch-long fragments and pushed into a borosilicate tube of a neon sculpture near the electrode. Vacuum is then pulled on the tube down to approximately 5 microns of pressure. The tube is then closed off and the electrode is heated using an automotive-type induction heater. In due time, this vaporizes the magnesium which then creates a reactive getter coating on the inside of the tube. This picks up any oxygen, water vapor, or other contaminants that may have been left inside the tube without the need for an oven vacuum pumping stage. The tube is then ready to be filled with neon. After about 24 to 48 hours of running, the getter coating will have picked up the contaminants and the tube will glow well.

It’s a useful technique, particularly for complex neon sculptures that won’t readily fit in an oven for pumpdown. If the glasswork is still too daunting, though, you can always use other techniques to get a similar look. Video after the break.

Continue reading “Making Neon Trees The Easy Way With No Oven Pumps Required” →

Neon Lamps — Not Just For Pilot Lights

September 13, 2022 by 30 Comments

It’s easy to see why LEDs largely won out over neon bulbs for pilot light applications. But for all the practical utility of LEDs, they’re found largely lacking in at least one regard over their older indicator cousins: charm. Where LEDs are cold and flat, the gentle orange glow of a neon lamp brings a lot to the aesthetics party, especially in retro builds.

But looks aren’t the only thing these tiny glow lamps have going for them, and [David Lovett] shows off some of the surprising alternate uses for neon lamps in his new video. He starts with an exploration of the venerable NE-2 bulb, which has been around forever, detailing some of its interesting electrical properties, like the difference between the voltage needed to start the neon discharge and the voltage needed to maintain it. He also shows off some cool neon lamp tricks, like using them for all sorts of multi-vibrator circuits without anything but a few resistors and capacitors added in. The real fun begins when he breaks out the MTX90 tube, which is essentially a cold cathode thyratron. The addition of a simple control grid makes for some interesting circuits, like single-tube multi-vibrators.

The upshot of all these experiments is pretty clear to anyone who’s been following [David]’s channel, which is chock full of non-conventional uses for vacuum tubes. His efforts to build a “hollow state” computer would be greatly aided by neon lamp circuits such as these — not to mention how cool they’d make everything look.

Continue reading “Neon Lamps — Not Just For Pilot Lights” →

Frequency Counter Restoration Impeded By Kittens

August 24, 2022 by 12 Comments

We think of digital displays as something you see on relatively modern gear. But some old gear had things like nixies or numitrons to get cool-looking retro digital displays. The HP 521A frequency counter, though, uses four columns of ten discrete neon bulbs to make a decidedly low-tech but effective digital display. [Usagi Electric] has been restoring one of these for some time, but there was a gap between the second and third videos as his workshop became a kitten nursery. You can see the last video below.

In previous videos, he had most of the device working, but there were still some odd behavior. This video shows the final steps to success. One thing that was interesting  is that since each of the four columns are identical, it was possible to compare readings from one decade to another.

However, in the end, it turned out that the neon bulbs were highly corroded, and replacing all the neon bulbs made things work better. However, the self-check that should read the 60 Hz line frequency was reading 72 Hz, so it needed a realignment. But that was relatively easy with a pot accessible from the back panel. If you want to see more details about the repair, be sure to check out the earlier videos.

We love this old gear and how clever designers did so much with what we consider so little. We hate to encourage your potential addiction, but we’ve given advice on how to acquire old gear before. If you want to see what was possible before WS2812 panels, you could build this neon bulb contraption.

Continue reading “Frequency Counter Restoration Impeded By Kittens” →

Neon, Ukraine, And The Global Semiconductor Industry

February 27, 2022 by 34 Comments

On our news feeds and TV channels at the moment are many stories concerning the war in Ukraine, and among them is one which may have an effect on the high-tech industries. It seems that a significant percentage of the world’s neon gas is produced in Ukrainian factories, and there is concern among pundits and electronics manufacturers that a disruption of this supply could be a further problem for an industry already reeling from the COVID-related chip shortage. It’s thus worth taking a quick look at the neon business from an engineering perspective to perhaps make sense of some of those concerns.

As most readers will know from their high school chemistry lessons, neon is one of the so-called inert gasses, sitting in the column at the extreme right of the Periodic table. It occurs in nature as a small percentage of the air we breathe and is extracted from the air by fractional distillation of the liquid phase. The important point from the above sentences is that the same neon is all around us in the air as there is in Ukraine, in other words, there is no strategic neon mine in the Ukrainian countryside about to be overrun by the Russian invaders.

So why do we source so much neon from Ukraine, if we’re constantly breathing the stuff in and out everywhere else in the world? Since the air separation industry is alive and well worldwide for the production of liquid nitrogen and oxygen as well as the slightly more numerous inert gasses, we’re guessing that the answer lies in economics. It’s a bit harder to extract neon from air than it is argon because there is less of it in the air. Since it can be brought for a reasonable cost from the Ukrainians who have made it their business to extract it, there is little benefit in American or Western European companies trying to compete. Our take is that if the supply of Ukrainian neon is interrupted there may be a short period of neon scarcity. After that, air extraction companies will quite speedily install whatever extra plant they need in order to service the demand. If that’s your area of expertise, we’d love to hear from you in the comments.

Here at Hackaday we are saddened beyond words at what has happened in Ukraine, and we hope our Ukrainian readers and those Ukrainian hackers whose work we’ve featured make it through safely. We sincerely hope that this madness can be ended and that we can mention the country in the context of cool hacks again rather than war.

If you are interested in the strategic value of inert gasses, have a read about the global helium supply.

Header image: Lestat (Jan Mehlich), CC BY-SA 3.0.