NVIS and VHF?
On May 24, 2:43*pm, (Dave Platt) wrote:
a *very* deep multipath
cancellation effect playing out... maybe interference between a
edge-diffraction path involving the office building, and reflections
from nearby trees. *
Not a Sea Story and relevant to my learning an important multipath
lesson:
In 1974, I was on an aircraft carrier at a pier in Long Beach
Shipyard. Ship's TV sigs not so good, so I ran a cable from the CPO
lounge TV out and up to a flight deck catwalk. On the catwalk, I
mounted a small all-channel antenna on a mast strapped to the rail.
The transmitters (Mt. Wilson) were located away from that side. All
very good pictures. In about two months, when the ship moved into
drydock, it was turned 180, so I rotated our TV antenna to
compensate. No good. Signals arriving across the flight deck were
all awful. Unwatchable.
I suspected reflections from the flight deck, so I moved the antenna
all the way aft, where it was receiving through clear air again.
Bingo! Even through the added 150' of cable I needed, we got our nice
pictures back.
"Sal"
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