i cannot believe that it is allowed (fcc rules?) to disturb the regular
reception of other AM stations in the locality! why do they let this happen?

"Drewdawg" wrote in message ...

"Charles Hobbs" wrote in message
...
Drewdawg wrote:
snipped for a smaller response
"WBRW" wrote in message
...

New Jersey's longest-running AM Stereo station, 930 WPAT in Paterson,
is now the first in the state -- and the second in the New York City
area -- to begin testing iBiquity's IBOC/"HD Radio" digital AM system.

Also, the digital data sidebands -- that now extend all
the way from 915 through 945 kHz on the dial -- will now cause a
constant "hash" or loud static type of noise to nearby channels such
as 910, 920, 940, and 950 kHz, as well as a constant hiss in the
background of 930 WPAT's own signal.

At my location in Somerset County, NJ, I hear WPAT's digital signal
causing a constant hiss in the background of 910 WRKL and 950 WPEN, as
well a loud "hash" on 920 kHz that severely degrades my reception of
otherwise perfectly clear WPHY, to the point where WPHY's signal is
only marginally intelligible. The "hash" on the other side of WPAT's
signal also prevents any chance of being able to receive 940 WADV.


IMHO this confirms what many of us believed from the beginning; IBOC
is
incompatible with analog AM. When HD stations start stepping on local
AM
second-adjacents, the time has come to re-think IBOC.

P.S.: read again
"as well as a constant hiss in the background of 930 WPAT's own
signal."

There is no better proof that AM-IBOC is incompatible with regular AM
radios.

How would DRM (as tested on the shortwave bands) fare?

Glad you asked :-) as I've proposed this on alt.radio.digital as IBAC-DRM
(in-band adjacent channel). If WOR were to stop IBOC and switch to
IBAC-DRM
at 720 I believe only that channel (720) would be affected, 700 would be
untouched, 690 & 730 would be completely unaffected and, my guess would
be,
710 would continue on at 10kHz without any hash on existing AM radios.

If today's situation is acceptable they could go dual-mode and do another
DRM at 700, giving them the fidelity heard on www.drm.org on their 40kbit
samples. Again, IMHO, same impact on 700 & 720, none on 690 & 730 and
normal AM on 710. However, I'm not an engineer and I could be wrong.
Sorry
if I am but please point out where I am. I'm curious as to how this would
be worse than IBOC.





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