August 2009 Nuts & Volts NixieNeon Clock

First a warning! This clock uses 120 volts and 160 volts which are present throughout the board. Handle the board carefully! On power-up, the clock will reset itself to 01:00:00. Reading the clock is fairly straightforward. The minutes are displayed on the two digits while the hours are displayed by the circle of 12 neon bulbs encircling the digits. Build this project in the August 2009 Issue of Nuts & Volts.

The time can be set by pressing the Min. Adv. or Hour Adv. buttons. When either of these buttons are first pressed, the clock will sequence to the time it has saved in its memory. Once it has set the time, pressing and holding either the Min. Adv. or Hour Adv. button will advance the minutes or the hours, respectively. You can go back and forth between the two switches setting the minutes and hours as needed. The clock will hold its time until the Pause button is pressed and released.
The rings can be run at an accelerated rate. This is useful for forcing rings to miscount. By pressing the Hold button and the Hour Adv. button simultaneously, the processor will take over and run the first ring. It will only be at a slightly different speed than normal. Pressing the Min. Adv. button will cause the processor to move to the next ring. Subsequent presses of the Min. Adv. button will cause the processor to sequence each ring. Pressing and releasing the Hold button will cause the clock to set itself to the current time, then resume normal operation.
Purchase a NixieNeon Clock kit in the Nuts & Volts Online Store

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