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Old February 27th 04, 01:01 AM
RHF
 
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= = = "Frank Dresser"
= = = wrote in message ...

"RHF" wrote in message
om...
.

FD,

If the IBOC Signal is a 'broadcast' as "Digital Encoded Algorithm".
Either as Dual IBOC Signals (Stereo) or as 'separate' Voice
and Data/Information Channels.

Then, how do you 'decode' it and Listen to it simply using
standard "Analog" SSB ?

~ RHF

.


I didn't take it as a method of decoding the IBOC signal. I took to
mean a way to minimize the interference from a IBOC station on a close
adjacent channel signal.

Let's say a station at 830 kHz is using IBOC and you want to hear a
station on 840 kHz. There's interference to the station at 840 from the
splatter of the main channel at 830 and the IBOC sideband centered at
843. You can minimize the interference from the IBOC sideband if you
listen to the station at 840 in LSB mode.

http://earthsignals.com/add_CGC/KMXE.PDF

Of course, normally it's preferable to listen to that station at 840 kHz
in USB mode, but the IBOC sideband interferes heavily with that
sideband.

Frank Dresser

..

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.

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.

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".

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" !

Oh Well - I have rambled on long enough.

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