Nixie Tube Clock ‘Frank 3’
Issue 5 (1 Jan 2012)
www.pvelectronics.co.uk
- 3 -
1. INTRODUCTION
1.1
About the clock
Nixie clock type ‘Frank 3’ is a compact design with all components and
tubes mounted on a single PCB. The efficient use of board space is
achieved by using a multiplex design to drive the display tubes. Only a
single high-voltage binary-to-decimal decoder IC (74141) is required,
and each tube is switched on in sequence very quickly to give the illusion
that all the tubes are actually lit.
The larger tubes for hours and minutes are type IN-12 with a digit height
of 18mm. The smaller tubes for the seconds are type IN-17 with a digit
height of 9mm. These tubes are Russian in origin and were produced
during the 1980’s, when the technology was at it’s most advanced. It is
expected that the tubes will last for very many years and should not need
replacing.
The optional wooden case and hardware pack (rear cover, screws),
supplied rough-machined, can be finished to give a very attractive clock
for everyday living spaces. The quality of the final finish will reflect the
time and care that is taken to finish the wood with successively finer
grades of sandpaper. Alternatively, you may wish to design your own
enclosure for the clock.
1.2
Clock Features
Nixie clock type ‘Frank 3’ has the following features:
- Hours, Minutes and Seconds display
- 12 or 24 hour modes
- Date display in either DD.MM.YY or MM.DD.YY format
- Alarm, with programmable snooze period
- Programmable date display each minute
- Attractive LED tube lighting
- Uses a Quartz Crystal Oscillator as the timebase
- Optional DCF/WWVB/ MSF/GPS synchronisation with status LED
- Supercapacitor backup. Keeps time during short power outages
- Simple time setting using two buttons
- Programmable leading zero blanking
- Five programmable neon colon settings (Flashing AM/PM indication,
illuminated AM/PM indication, both flashing, both on, both off)
- Seconds can be reset to zero to precisely the set time
- Programmable night mode - blanked or dimmed display to save tubes
or prevent sleep disturbance
- Separate modes for colon neons during night mode
- Standard or fading change of digits
- ‘Slot Machine’ Cathode poisoning prevention routine
- All user preferences stored to non-volatile memory
