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The design of this clock is pretty much stable. No new changes have been mad in quite some time.
New software release 1.00.11.

Fixed bug in pendulum Mode 0 which would only light some of the quarter hour lights on after a razzle. The lights are now forced on.

New software release 1.00.10.

Modified the code to write the clock's sense of the time out to the rtc before each razzle (auto or otherwise). This compensates for the inaccuracy of the crystal on the RTC board.

New software release 1.00.09.

Restricted the minimum time that sync time can be set to 60 seconds. Times less than that can make it hard to comunicate with the clock.

New software release 1.00.08.

Modified to detect and use the RTC on power up if it's present.

Modified to detect AC or DC power and generate 60hz if DC power is detected. (This only works for 14.7456MHZ crystals).

Reduced the help messages as well as other strings to make room for the above changes.

New software release 1.00.07.

Modified to have pendulum mode 0 set the lamps always on.

Modified to have the sync time to always occure at the top of the interval (an interval of 3600 will be the top of the hour)

New software release 1.00.06. Modified code to calculate the current time directly from the zero crossings without converting to milliseconds first to eliminate the rounding errors that were occurring.
New software release 1.00.05. The code was modified to allow advancing the minutes and hours by clicking the buttons as well as just holding them down.
These are the complete schamatics for the nixie tube clock. Printable version are included in the assembly document which can be viewd by clicking here (pdf) (this is a rather large file).

Click on the schematics below to view a full sized version.

Schematic 1 - Power Supply

Schematic 2 - CPU

Schematic 3 - 60hz Ring Counter

Schematic 4 - 6hz Ring Counter

Schematic 5 - 1 Sec. Ring Counter

Schematic 6 - 10 Sec. Ring Counter

Schematic 7 - 1 Min. Ring Counter

Schematic 8 - 10 Min. Ring Counter

Schematic 8 - 1 Hour Ring Counter

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