As far as hacker clock builds go, the more obscure the parts involved, the better. By this yardstick, [sjm4306] has a great piece on his hands with this Numitron-based build.
The Numitron was a type of display popular in the 1970s, and often used in aircraft avionics and other high-end hardware. The display is a 7-segment type, but using filaments instead of LEDs. [sjm4306] was able to lay his hands on four of these devices, along with some bulbs to act as the digit seperator and AM/PM indicator. Due to being incandescent in nature, multiplexing wasn’t a practical option, with lower duty cycles drastically dimming the display. Instead, a 32-bit cascaded shift register was used to enable all the segments to be driven at the same time.
It’s a great build that uses some genuine original display hardware to create a clock with a compelling vintage aesthetic. This would make a great gift to a pilot from the era, or any hacker that likes the unusual display technologies of yesteryear. You can even build a Numitron watch, if you’re so inclined. Video after the break.
13 thoughts on “Numitron Clock Is A Tidy ’70s Throwback”
I’m pretty sure the 1971 Cessna 172 I got my pilot certification in, back in 2000, was still using these for its Bendix/King radios. They sure looked good and they were clearly visible in broad daylight or in the middle of the night.
My Numitron clock lights up my entire living room at night with the lights off. No need for a night light.
Thumbs down from me. Just a video, no blog post describing it.
For some things, like demonstrating how to use a brake drum puller, video is helpful. For circuits and similar electronics, video sucks.
I wonder if it would be possible to make a similar looking display using some of those newer “Edison” style LED bulbs. Buy the bulbs, rip out the LED strips and mount them in a 3D printed case that holds 7 strips.
I still have some of these displays purchased from RadioShack (Tandy) many years ago. It may be fun to dig them out and build something with them.
DO IT! …and make sure we all know about it :)
Spelling – it’s unnecessarily atrocious.
I’m aware you can’t enforce spell check during publish in WP (at least, not practically.. especially on a tech site.
There isn’t any web browser in widespread use that won’t put a red inchworm under “seperate”.
For an author to ignore that visual means that a “good faith effort” isn’t even attempted.
Sorry if this is considered petty these days.
I like the olde-timey look of the circuit board. More projects like this, please!
is possible make other shape?
Is it a bad sign if I have some of these displays which I bought back when they were new for a project “I’m about to get to one of these days…”?
Lol, I have a drawer full of parts that I bought for specific projecta but never got around to using.
Hello would it be possible to drive the KW-104s digits with a MAX7219 chip?
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