"StephenH" wrote in message
m...
This is where the HFCC should come in. If DRM is going to be taken
seriously, even by long-term hardcore DXers, then it can't be made to
co-exist smack back in the middle of established AM broadcasts. There
*has* to be a "DRM corner", on a few or all of the broadcast SW metre
bands. Initally, a space of 50 to 100 kHz on each band, dedicated to
DRM only broadcasts. Where this might be allowing more capacity than
required for DRM in the meantime, it should allow DRM to grow a little
more - possibly to the extent where it might begin to be commerically
attractive/viable - with NO impact on existing AM broadcasts. As time
goes on, increase the DRM "band" while reducing the AM band. AM
doesn't need to disappear completely, nor do I believe it will. (Same
with FM vs DAB/IBOC)
Why reduce the AM shortwave broadcast band at all? The AM SW BC bands have
been expanded since the SW commercial utility stations have mostly left.
Just let some of the new expansions go to DRM.
But there must be more to it than this. Maybe I'm making it sound too
simple, there *must* be a real, logical reason as to why this approach
hasn't already been taken. Otherwise, doesn't this approach solve
most problems with interference, whilst giving DRM the space it needs
to grow a little more?
Stephen Howie,
Reading, U.K
Maybe a station is equipped and licensed to operate on a certain frequency,
so that's where they operate, DRM or AM. The real, logical reason might be
that nobody though much about interference until now, and the implementation
is haphazard.
Frank Dresser
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