"Kristoff Bonne" wrote in message
...



Come to think of it. Why use different frequencies? DRM is able to
handle SFNs (single frequency networks)!

If you would broadcast your signal from (say) two or three different
transmittor-sites, if fading causes one of the signals to drop away, the
signal from the other site(s) will continue to be received.

It would be interesting to see how much power you would need from these
three transmittors together compaired to how much is needed if you only
use a single transmittor.


In the VHF-range, single-frequency networks allow for lower
transmission-power.
(due to the fact that the radio-signal is broadcast from multiple
points, a receiver will receive radio-signals from different directions
so there is more change of a signal coming in with a good quality).

It would be interesting to know if the same thing applies for HF!



Cheerio! Kr. BBonne.

It's worth remembering all the commercial SW data and phone links which were
in use before the satellite era. They had diversity reception,
sophisticated (for the time) digital modes, high power transmitters, high
gain antennas, etc. Yet they abandoned their large investment in SW as
satellites became available. Even with all their technology, SW still
wasn't reliable enough.

I think the average person expects at least the same order of reliablity
from their radios.

Frank Dresser