"RHF" wrote in message
om...

FD,

I can understand what you are saying, IF (Big 'if') I was trying
to get away from one interfering IBOC Side-Channel.

BUTT (Big 'butt' ) What happens when there is 50% implementation
of IBOC and on average every other Channel is an IBOC Broadcaster
with an IBOC Side-Channel at both +15kHz and -15kHz.

So now your Old Fashion AM Station at 840kHz has a 860kHz Lower
IBOC Side-Channel and also a 820kHz Upper IBOC Side-Channel;
both sitting within -&+ 5kHz of 840kHz.

This will have to make reception tough in the station's fringe areas. I
don't know what area the FCC protects, but the figure of 700 miles for
the "clear channels" comes to mind. It's unclear if there will be any
problem in each of the station's home cities. But the NRSC (not the FCC
as I posted earlier) has stopped nighttime IBOC tests


As, I read and interpret the Spectrogram the IBOC Signals are
about 12 dB above the band scan base noise level. The Main
AM Signal is another 18 dB above the IBOC Side-Channels.

While IBOC may be 'claimed' to be backwardly compatible with
the current AM Broadcast media. It is apparent to me that with
may be 33% IBOC adoption the AM Band as we know it will cease
to be; and all remaining AM Band Broadcasters will be FORCE by
the 'new' IBOC Noise Levels to transition to IBOC or NOT Be Heard.


Only if the interference effects radio stations in their home market.


IBOC to IBOC will not be a problem because of the specific IBOC
Side-Channel Off-Set and the Encoding and Decoding of the IBOC
"Digital Algorithm".


I don't know how well this system will perform, but I suspect the
digital sidebands will be interfering in areas where the received signal
isn't much stronger than the interfering signal. That is, I don't think
digital will save digital from digital.




BUTT - To the old fashion AM Analog Radio Station the IBOC "Digital
Algorithms" from the upper and lower adjacent IBOC Side-Channels
will simply sound like NOISE "BIG TIME" !


And 95% of the listeners will never notice the interference. But
there's no guarantee they will want the extra "features" digital radio
promises, especially if they have to pay extra for digital radios.


Oh Well - I have rambled on long enough.

iboc ~ RHF
= = = I Be Overly Concerned !
.

http://www.rwonline.com/reference-ro..._rw_iboc.shtml

Frank Dresser