My old Casio "Waveceptor" watch could receive the UK MSF (formerly Rugby Clock) or German DCF77 signals. It used to be great, but when the transmitter moved from Rugby to Cumbria the signal seemed to have got weaker and my watch rarely managed to synchronise.
I have a number of clocks around the house that sometimes show incorrect times and dates due to poor reception (and presumably lax error checking) and I had considered building a low power MSF transmitter to make sure they show the correct time. I haven't done so because broadcasting on those frequencies would be illegal in the UK.
One quick warning: You may see some mentions on the web about using a Pi GPIO pin as a transmitter. Don't do that! It produces a very bad waveform and produces messy harmonics that bleed all over the radio spectrum. I only mention this as a warning not to do it that way (get a proper transmitter module instead), and that any posts suggesting or asking about that method get deleted from these forums (the moderators get very upset).
I have a number of clocks around the house that sometimes show incorrect times and dates due to poor reception (and presumably lax error checking) and I had considered building a low power MSF transmitter to make sure they show the correct time. I haven't done so because broadcasting on those frequencies would be illegal in the UK.
One quick warning: You may see some mentions on the web about using a Pi GPIO pin as a transmitter. Don't do that! It produces a very bad waveform and produces messy harmonics that bleed all over the radio spectrum. I only mention this as a warning not to do it that way (get a proper transmitter module instead), and that any posts suggesting or asking about that method get deleted from these forums (the moderators get very upset).
Statistics: Posted by rpdom — Sat Oct 18, 2025 10:08 am