Nixie Clock ‘SN18’
www.pvelectronics.co.uk
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1. INTRODUCTION
1.1
About the clock
Nixie clock type ‘SN18’ is a Single Digit Nixie Tube Clock.
It can be used with two types of tube: IN-18 with a digit height of
40mm or type IN-8 with a digit height of 18mm. These tubes
originated in the USSR.
How can the clock display the time with only a single digit?
The clock flashes up the time in the sequence HHMM, with
appropriate pauses between each digit,and a longer pause between
each time cycle ie. H.H...S.S.....H.H...S.S.... and so on. It is really
very intuitive, and once you 'get it', it is really obvious and simple
to read the time!
1.2 Clock Features
Nixie clock type ‘SN18’ has the following features:
•
For IN-18 or IN-8 Nixie tube
•
12 or 24 hour time display
•
Adjustable night blanking period, with adjustable override period
•
Alarm, with snooze
•
Customisable snooze period (6,9,12 or 15 minutes)
•
Crystal timebase, with software calibration
•
Optional WWVB or DCF77 synchronization
•
Software shutdown of HV for optimum WWVB or DCF seek
•
Auto night-synchronisation for optimum signal reception (user-
configurable)
•
Blue or white LED underlighting of Nixie tube, software configurable
for following night-blanking or not
•
Multifunctional LED for seconds:
o
No WWVB or DCF77 sync in the last 24 hours: flashes red
o
Valid WWVB or DCF77 sync in the last 24 hours: flashes green
o
Currently acquiring a WWVB or DCF77 frame: flashes red/green
•
Time backup for ~1 hour in case of power outages
•
AM / PM indicator LED
•
4 display modes including 2 fade modes (slow and fast)
•
All user settings and preferences stored to flash memory
