Nixie Tube Clock ‘Frank 3’
Issue 5 (1 Jan 2012)
www.pvelectronics.co.uk
- 27 -
7. USING A RADIO FREQUENCY TIME RECEIVER OR GPS
RECEIVER
The clock can automatically synchronise time from DCF (Europe),
WWVB (USA), and MSF (UK) long wave time transmitters.
The clock can also receive time from a GPS receiver that transmits
information using NMEA-0183 protocol, using the $GPRMC
sentence.
7.1 Configuring for RFT or GPS Synchronisation.
•
Set parameter 12:
1: DCF
2: WWVB
3: MSF
4: GPS
•
If using GPS, set the baud rate in parameter (13)
•
Set parameters 14 and 15 for the hours and minutes your time
zone is offset from the synchronisation source. This is usually
only whole hours. Examples:
o
Eastern USA is 5 hours offset from UTC transmitted by the
WWVB transmitter.
o
UK is 1 hour offset from the time transmitted by the DCF
transmitter
o
France has no offset from the time transmitted by the DCF
transmitter
•
Set parameter (16) to identify whether the offset is minus (0) or
positive (1) of the time source.
•
If using WWVB source, and you do NOT require automatic DST
adjustment (eg. Arizona does not observe DST), then set
parameter (17) to 1.
•
If using GPS, parameter (17) acts as a DST bit. Set to 1 during
DST period, and 0 during standard time period.
•
Set parameter (23) to select between hourly seek and daily
seek in DCF / WWVB / MSF modes.
•
If you have selected daily seek, use parameter (24) to set the
time of the daily seek in DCF / WWVB / MSF modes.
•
If you intend to place the RFT receiver module closer to the
clock PCB than 6 ft / 2 metres, the clock will need to disable HV
and switch off the tubes for time seek, otherwise the switch-
mode power supply will prevent reception. Select blanking
during time seek by setting parameter (25) to 1. Leave as 0 to
keep tubes lit during time seek.
