Hello everyone, I just recently started using my gps/pps setup for chrony (@Bas not using google anymore ). I wonder if it is possible to make a little beep (like wwv or the others) every second? I am using a rasberry pi 4 which is capable of transmitting. Would I need to directly use /dev/pps0?
What type of radio signal do you want to use?
As you are not allowed to transmit freely without approved equipment.
As for PPS0, I do not use it with my USB-PPS-GPS, I use this on /etc/default/gpsd:
# Default settings for the gpsd init script and the hotplug wrapper. # Start the gpsd daemon automatically at boot time START_DAEMON="true" # Use USB hotplugging to add new USB devices automatically to the daemon USBAUTO="true" # Devices gpsd should collect to at boot time. # They need to be read/writeable, either by user gpsd or the group dialout. DEVICES="/dev/ttyUSB0" # Other options you want to pass to gpsd GPSD_OPTIONS="-n"
And in chrony.conf, this for GPS usage:
refclock SHM 0 refid GPS poll 3 precision 1e-3 offset 0.127 refclock SHM 1 refid PPS poll 2 precision 1e-9 lock GPS prefer
As for the beep, why not simply use a 1-sec crontab to make the beep? Your systemclock should be spot on, so crontab would be too (or very close).
Transmitting with a RPi is not advised as it doesn’t contain harmonic-filtering and you could end up in big trouble if you disturb importent systems near you.
Best not try that without knowledge of transmitters.
Bas - ON5BAS.
I remembered something like Project: μWWVB · cat /var/log/build a while back. It’s not what you want.