[BC] AM Ground Systems & Ground Conductivity

[Thomas G. Osenkowsky]

Do not confuse ground conductivity with ground
system efficiency. They are very different. In CT
and New England, you are lucky to get a 0.5
conductivity! M3 is much more optimistic and
many stations have been granted power increases
based on measured data, especially when probe
measurements are conducted in the middle of
summer.

Some stations have used barbed wire for radials.
I don't know about a waiver for shorter radials.
I would inquire if there is a precedent for this,
or perhaps an exhibit demonstrating compliance
with minimum efficiency Rules may help. Being
on the high end of the band is a handicap. Your
tower is 86 degrees which is good. An efficient
ground system is critical where ground conductivity
is low and the frequency is high. As far as the
base impedance is concerned, it is important to
know if it was measured when the antenna had
a full or compromised ground system.

Tom Osenkowsky, CPBE