[BC] More at Night,less Day

[Dan Strassberg]

I'd be surprised if there were fewer than 200 US AMs that now operate with
greater power at night than during the day. A large percentage are Class Cs
whose day power is limited to protect first-adjacents. At night, those
protections don't apply because the protected stations have such high NIF
values. So the first-adjacent Class Cs can use higher night power.

One or two stations operate with night powers 10 times as high as their day
powers. The first of these was KFMB, which runs 50 kW directional at night,
protecting WJR. KFMB's day power is limited to 5 kW-ND to protect KBRT. KBRT
is second adjacent to KFMB and transmits from Catalina Island. KBRT is owned
by Crawford, a Christian broadcaster with which I am sure Willie is
familiar. By no means, however, was KFMB the first US AM to operate with
higher power at night than during the daytime.

Curiously, the FCC Media Bureau and the US's largest Christian broadcaster,
Salem Communications, seem to be on a mission to reshape the Hawaiian radio
dial to increase nighttime protections to Hawaiian AMs, several of which
which are co-channel with west-coast AMs that Salem owns. At one time, I
think it was just assumed that since Hawaii is about 2500 miles from the US
mainland, interference to Hawaiian AMs from stations on the mainland
couldn't be significant. During that era, KFMB was moved to the then IA 760
channel, whose only two US occupants were WJR and Hawaii's oldest AM, KGU.
(The reason for this move was a treaty that turned 540, the frequency on
which KFMB then operated, into a Canadian/Mexican IA channel, necessitating
KFMB's move.) Later, KFMB was granted an increase to 50 kW at night sending
the equivalent of more than 100 kW at night toward KGU. Although Salem owns
it, KGU does not appear to be one of the stations affected by the Hawaiian
reshuffing. Salem does not own KFMB, however. The reshuffling in Hawaii
involves moving a handul of stations to adjacent channels. I believe that
KGU could move to 750 and on that frequency would receive less interference
from KXL than it currently receives from KFMB, but for some reason, KGU is
not among the Hawaiian AMs affected by what appears to be the largest mass
AM frequency move since NARBA, 65 years ago.

--
Dan Strassberg, dan.strassberg at att.net
eFax 707-215-6367