On 2/10/2012 1:11 PM, Milt -- N5IA wrote:
> If that is the case, WHY do the pro broadcasters install all 120 radials at
> full length; even bare wire buried a couple of inches underground?
Answer:
Because the FCC requires it as part of your AM application. Some
stations that were required to protect a distant station on the same
channel but away from the area they wanted to cover, even applied for a
waivers with a deliberately poor ground system in the protected
direction ...but the FCC said no way Jose. Another consulting engineer
when modeling a slant wire shunt fed and running test FSM noticed some
cancellation in the opposite direction of the slant wire shunt fed
tower. This appeared a sensible solution to enhanced protection without
the addition of another tower and expensive pahser, not to mention the
cost of additional real estate. Again the boys at 1919 M Street said
no. (The Portals today)
With the price of copper skyrocketing the amount of theft in some parts
of the country is unbelievable. AM stations are immediate targets as
thieves just pull up the systems with a winch or just hook it to the
bumper and drive off into seclusion and roll it up in the back of a
truck. Some station owners in PR have opted to plow in barbed wire as a
lower cost alternative to bare copper. So far none of the barbed wire
buried ground systems have not been touched.
Herb Schoenbohm, KV4FZ
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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