I have worked in the technical end of radio broadcasting since 1965. The
stations that I worked for have lost listeners and a great deal of coverage,
due to RFI. I can’t begin to count of the number of times that I’ve been asked
to call a listener who complained that they can no longer hear a station that I
was responsible for. This is happening with a station running 25 kW on the
lower end of the band.
There are other reasons for the demise of AM broadcast radio, but RFI from
power lines, computer networks, switching power supplies, CFL and LED light
bulbs and other devices has been a significant contributor.
Probably the reason you don’t see much about it in the broadcast trade
magazines is that there isn’t much of anything a station can do about it other
than waste time playing whack-a-mole.
Gary
I've only seen RFI mentioned in passing a few times in Radio World a broadcast
magazine. Doesn't seem to be an issue for broadcasters typically operating
from 5,000 watts to 50,000 watts.
If you think about it, it's not going to be much of an issue to local AM
broadcasters who are using very strong local transmissions on ground wave to
the receivers. They may only lose fringe or rural area listeners, and only if
those listeners get solar systems. Compare that to amateur radio operators
running only 100 watts (typical) or less or rarely up to 1,500watts (max)
transmitting through the ionosphere once or multiple times with 40-70db or more
of loss and requiring highly sensitive receivers to pick up the weak signals.
Most AM broadcasters won't be affected much at all with minimal loss of
listeners. But Amateur Radio will be.
73, de ed -K0iL
_______________________________________________
RFI mailing list
RFI@contesting.com
http://lists.contesting.com/mailman/listinfo/rfi
|