On Aug 2, 5:13 am, Doug Smith W9WI wrote:

It also includes an "alternate frequency" field. This idea came from
Europe where a single station may have a number of transmitters on
different frequencies. The station places all its frequencies in the "AF"
field on all its transmitters. If the radio senses the signal it's tuned
to isn't coming in well, it tries the other frequencies in the AF list,
looking for a better choice.

This is very handy when you're driving cross-country. The car
radio can hand off from one transmitter to another, while staying
on the same network. This presupposes national radio networks,
of course. :-)

They also have the ability to switch to a different station for
traffic reports, then switch back to whatever you were listening
to. This is sometimes jarring, but I understand the reasoning.

We have nationwide radio networks in Canada from the CBC,
but don't use RDS. Too many AM transmitters to make it work;
probably other issues too.

We played with DAB for a while on L band, but have quietly
walked away from it. There's just one multiplex still on the
air here in Vancouver.

I've often thought wide band FM ham radio (e.g. 10 GHz)
could benefit from RDS ("VE7LDH 10.2 GHz QTHR QSL via buro").

Laura Halliday VE7LDH "Non sequitur. Your ACKs are
Grid: CN89mg uncoordinated."
ICBM: 49 16.05 N 122 56.92 W - Nomad the Network Engineer