WWZN and Kinstar antennas

Dan Strassberg dan.strassberg@att.net
Tue May 9 17:23:43 EDT 2006

As AM facilities, go, though, WWZN's array is fairly new--25 years. Still, I
guess the ratchet rule wasn't yet in force when it was built, but it might
have been. For example, I can believe that WWZN's night groundwave toward
Sherbrooke is 10% less than that from the old 5 kW facility. And the tall
towers must further reduce the radiation over the critical angles for
Sherbrooke, which is something like 200 airline miles from Waverly Sq.

The big potential issue is whether the new method of calculating the NIF,
which takes into account first-adjacent 10% skywaves, was in effect in
1980-81. If not (and I bet that this is the case), WWZN's NIF has to be
dramatically understated. The Boston 1510 is one of those rare birds--a
legacy Class B that has been on its Class A channel so long that it actually
receives protection from the co-channel Class As (both WLAC and KGA,
although Boston is so far from Spokane that I can't imagine that KGA has to
do much to protect WWZN). So my guess is that if you ignore the first
adjacents, WWZN has a really, really low NIF (maybe less than 3 mV/m). But
since WTWP and WWKB don't protect WWZN at all, they together might easily
raise WWZN's NIF to 25 mV/m or more. If that's the case, WWZN may not
deliver an NIF signal to 80% of Boston, let alone 100%. The FCC usually
grants waivers of CoL NIF coverage requirements to AMs that are forced to
change facilities due to loss of a transmitter site. But that would not be
the case with the scenarios we're talking about here. Of course, WWZN could
become a daytimer ;>) And it could move in with WMKI. For sure the WMKI
array would allow WWZN to adequately protect WLAC from daytime skywave, even
while running 50 kW. And at mid-day, WWZN could run 50 kW-ND. Then, whenever
another AM filing window opened, the CoL could be changed to Quincy or
Milton. I think WWZN could run 5 kW or something close from the WMKI array
and would probably cover one of those communities well enough to be licensed
as a Class B.

----- Original Message -----
From: "Scott Fybush" <scott@fybush.com>
To: "Aaron Read" <readaaron@friedbagels.com>
Cc: <boston-radio-interest@bostonradio.org>
Sent: Tuesday, May 09, 2006 3:39 PM
Subject: Re: WWZN and Kinstar antennas

> There's another, much bigger problem that WWZN would subject itself to
> if it were to make a voluntary move of its night transmitter, and that's
> the FCC's well-meaning but misguided ratcheting rule, which I could
> expand on at mind-numbing length if anyone's interested...
> s

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