Picture of The Tnychron Clock
Have you ever seen a pocket calculator from the 1970s? If you have, you know that many used a series of tiny, red, LED seven-segment displays. These displays used little "bars" of light-emitting material which were placed behind little magnifying bubbles to make them more readily visible. They were very crisp and readable, and used a lot less power than vacuum fluorescent displays (VFD), which were also in use at that time.

I recall the little LED bubble displays were at one time in all sorts of handheld electronics and, in a slightly different form, watches. By the time LCDs became cheap in the late 1970's, the more power-hungry LED display was on its way out.

I was pleasantly surprised back in 2011 to find on ebay a seller with numerous rails of HP 5082-7433 LED displays. These are three-digit displays in a 12-pin standard DIP format. I bought a few rails since the price was good. I've a tendency to get "stuff" and then never get around to using it so I decided this time there would be a project to make use of all the displays.

The "Tnychron" clock was born!

Step 1: Design

Picture of Design
Design requirements:
- 1970s-looking retro case
- Arduino IDE environment project
- use the HP displays effectively
- make it play music
- make it easy to use
I love clocks!
uhclem (author) 1 year ago
I really wanted to find right-angle switches with long buttons and have the button part poke through holes on the rear plastic. I couldn't find them at the time.
Spannerz1 year ago
Just my two cents, but (if you had the room) I would use fixed push-momentary switches on the back and solder them to the board via wiring that way, saves gaping holes (but I don't know if you could have shrunk the board any more?)
This is a great clock, I love the displays and the angles on the enclosure, has a very "futuristic in the 1970s" feel about it. Thank you for sharing it with us.
topcat52 years ago
Very Nice.

And nice job on the retro look. Have a look at the Heathkit GC-1092 electronic clock kit that was sold in the 1970s. Very similar looking. It was the fancy version of the GC-1005.
uhclem (author)  topcat52 years ago
Thank you. I do recall the 'regular' version of the Heathkit clock. I have a set of the panaplex displays and sockets as used in the clock. One of these days I ought to build one.
rocketguy2 years ago
Niiiiice! I still have my dad's HP calculator with the red bubble display. Seeing this makes me feel all warm and fuzzy inside. Great work!
Aleator7772 years ago
I really love the style of this. I'm a big fan of retro display technology. Good work!
uhclem (author)  Aleator7772 years ago
Thank you!
thegrendel2 years ago
Wunderbar! The LED clocks of a previous generation
had a look and feel that can't be duplicated by the modern
hi-tech alarm gadgets. And, recall that the very first run of
digital clocks, around 1972, retailed for thousands of dollars.

Thanks for a great project.
amotoalain2 years ago
Very nice clock,
uhclem (author) 2 years ago
For those wishing to build this you can also buy the board directly from BatchPCB via this link: https://www.batchpcb.com/pcbs/97355.

As for the displays, if you can't find the originals, there is an eBay seller who currently has a unified 9-digit, 7-segment bubble display which is common-cathode and could definitely be made to fit in the Serapac A20 case.
If you had this as a kit I'd buy it.
uhclem (author)  mettaurlover2 years ago
Hi there. I only have it available as a built clock or just the PCB. If you can find the displays, everything else is easy to source from the larger parts suppliers.
ajoyraman2 years ago
Great work ! A combination of vintage, current, & imagination makes an excellent project.
uhclem (author)  ajoyraman2 years ago
Thank you for your comments.