This clock is based on the CD81-6-V3 design, but it only uses a single tube to display the time.
The tube used here is a Z570M. The PCB is only 51mm x 51mm (2" x 2"). Further details.
With only one tube, the time is displayed in a sequence of 4 numbers. eg, 10:25 is displayed as 1-0-2-5.
There is a small pause between each 3 second display cycle, so you can recognize the start of the cycle.
Here's a short QuickTime video-clip of the clock in action. Notice how the digits fade in and out. Nice!
Pictures:
| Mouse over the image below... Front and Back views. |
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The enclosure is a 'UV Protected' Baseball display box. Effective, and cheap. Not bad!
Mmm, I'm not sure about that red coating on the Nixie though - yes, it has to go!
| PCB underside |
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After soaking the tube upside down in a glass of warm water for a few mins, the red platic skin just slid off.
Personally, I prefer the tube clear like this. The digits are sharper, and blue LED effect looks much better too.
| Nice and clean |
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It's 16:48...
Additional files: