I would like some advice on what is the most proper and effective way
to issue a complaint with the FCC regarding harmful interference being
caused by a radio station that is using the IBOC digital system.

The station in question is 710 WOR in New York City, which has been
using the IBOC digital system since October 2002. And since that
time, they have been causing harmful interference to frequencies as
far as 40 kHz away from their carrier -- across a region of at least
680 through 750 kHz.

I have observed this interference throughout northern and central New
Jersey -- at locations up to and beyond 50 miles away from WOR's
transmitter site -- on a wide variety of receivers, ranging from
highly selective car radios to hi-fi AM Stereo receivers. And
tellingly, this interference completely disappears the instant that
WOR stops transmitting their IBOC digital sidebands at sunset each
day.

Of course, I understand the fact that the IBOC system is designed to
occupy a 30 kHz total bandwidth, including 15 kHz above and below the
station's carrier. Thus, when WOR's IBOC is in use, I do not expect to
be able to receive anything but noise on 700 and 720 kHz, and I expect
my reception on 690 and 730 kHz to be severely degraded, if possible
at all. That is indeed what I am observing, but that is not my
complaint.

My complaint is about the scratchy, crackly type of "splatter"
interference that WOR is causing to be heard on 680 through 750 kHz
whenever their IBOC system is in use. This interference varies in
intensity in accordance with WOR's analog modulation -- the "louder"
their audio is, the more severe the interference is. Thus, by these
indications, this interference appears to be very similar in nature to
the wideband splatter caused by an analog AM station that is
consistently exceeding the -100% negative modulation limit, or by a
station whose directional antenna array is affecting their signal to
such a degree that a similar receiver-based effect is being produced,
especially towards the signal's "nulls".

Having mentioned this to WOR's engineers numerous times, their claim
is that according to the modulation monitor and spectrum analyzer at
their transmitter site, WOR's radiated signal (with IBOC in use) falls
within the NRSC radiated emission limits, and therefore is "legal" --
end of story. They have refused to conduct any field measurements
that might support or dispute my claims, other than "it sounds fine on
my car radio". In fact, WOR's engineers have even threatened legal
action against me, because of my claims that WOR is operating
"illegally". Needless to say, this has resulted in a breakdown in
communication between them and I. I have chosen not to discuss this
issue with WOR's engineers any longer, because nothing was being
accomplished.

But now that WOR has made headlines in national radio publications,
boasting about the success of their IBOC installation, I feel the time
has come to address these issues, and put it in the hands of the FCC
and more capable engineers to decide whether or not WOR's IBOC signal
is causing harmful interference and/or is exceeding the FCC's radiated
bandwidth specifications. In particular, WOR's Director of
Engineering brings into question the performance of their directional
antenna array and how it may be affecting their IBOC signal -- stating
in his Radio World article, "It should also be noted that the pattern
bandwidth of our null is not great. On a spectrum analyzer, WOR's
upper sideband does not exist north of Paramus, NJ".

Obviously, that kind of problem can seriously degrade an analog AM
signal, and would be particularly harmful to the quadrature-modulated
component of an AM Stereo signal. But what would the complete lack of
an upper sideband do to an AM IBOC signal, which also makes use of
quadrature modulation? That is a big question mark, because nobody
has ever addressed it before -- not the FCC nor the NRSC -- and
because WOR's engineers are apparently not concerned about it enough
to conduct any field tests with and without their IBOC signal in use.

Obviously, as one of the very few AM stations in the world using the
IBOC system, WOR is essentially "flying by the seat of their pants" --
and in that regard, I can cut them some slack as they continue to
experiment with it. But to consistently ignore and dismiss these
interference issues is a serious problem -- especially during these
short winter days, when skywave propagation during the early morning
and late afternoon "critical hours" can cause WOR's IBOC signal to
interfere with distant stations, including several in Canada, such as
690 CINF and 730 CKAC in Montreal and 740 CHWO in Toronto. In fact, I
distinctly remember tuning in 740 kHz on my car radio a full hour
before local sunset and hearing CHWO's signal coming in with heavy
interference from WOR's IBOC "splatter". That was observed in
Princeton, NJ, nearly 50 miles away from WOR's transmitter site.

So, to sum up this long-winded message up, since my attempts to
address these issues directly with WOR have failed, how should I go
about bringing it to the FCC's attention? Hopefully they can take
some time our from their crusade against non-existent
third-adjacent-channel interference from LPFM stations to address a
much more significant interference issue on the AM band....