WPTR/WDCD-1540, sandy soil in the area
Sat Jun 28 10:47:54 EDT 2008
The Albany, NY region has some sandy areas that, due to the prevalence
of pitch pine woodlands, bear a striking resemblance to Cape Cod along
Sandy soil, of course, has very low conductivity.
When you go from a quick transition from sand to salt water, as on the
Cape, you wind up with startlingly directional performance at that
boundary. Probably something you'd need a 5-tower array to replicate
in a homogeneous-ground-composition area.
The radio locator site's maps show this very well on sandy-shore
"non-directional" graveyarders like Atlantic City (1340, 1400, 1450,
1490) and Cape Cod (1240).
Reception of long-haul overseas signals from these coastal boundaries
is also very common - aided both by the salt-water gain and also by the
sandy soil reducing what's coming from inland sources of interference.
Mark Connelly - Billerica, MA
Due to some weird anomalies in the ground conductivity in the Capital
District, WPTR also has a pretty poor signal in parts of Albany just a
few miles from the transmitter site and is uncompetivie in the
northern Hudson Valley anywhere south of East Greenbush--an area that
is an essential part of the market. Back when WTRY was DA-1, it had a
better signal in all parts of the market except for Saratoga Springs,
where it could not cover well because it had to protect the 980 in
Montreal (since moved to 990). In the early to mid 60s, WTRY changed
from DA-1 to DA-N, which took care of Mechanicville and Saratoga by
day and increased the daytime signal strength in Schenectady as well,
at the expense of the signal strength in Albany and Troy. In Troy, in
particular, the signal strength remains very strong, however.
WPTR signed on in 1947 or 1948 with 10 kW-U DA-1 using the same
transmitter site, half-wave towers and pattern that it uses to this
day with 50 kW-U. In only a year or so, the station had increased to
50 kW-U. Supposedly, the increase was granted so quickly because the
signal in downtown Albany was so pathetic. Back then, AMs were
required to deliver 25 mV/m to the "principal business district" of
the CoL. Depute running 50 kW-U directionalized to the north and east
from a site on the Albany-Schenectady Rd midway between downtown
Albany and downtown Schenectady, WPTR, couldn't come close to 25 mV/m
in downtown Albany. Even after the increase to 50 kW-U, the signal in
downtown Albany could not be characterized as a "solid" 25 mV/m!
Meanwhile, in downtown Schenctady, an equal distance from the WPTR Tx,
the signal exceeded 75 mV/m!
Dan Strassberg (email@example.com)
More information about the Boston-Radio-Interest