jcarlyle wrote:

One hardware change I plan on making soon is to move my PCAS antenna
from the instrument panel area to a location back in the tail boom. My
PCAS antenna is now getting shadowed from multiple directions by
various instruments from the rear and below, by the compass from the
front and above, by the canopy and instrument panel lifting mechanism
from the front, and by the rudder pedal assembly from the front and
below. In the tail boom the only real shadowing will come from the
landing gear from the front. Shadowing of the PCAS antenna in its
present location might explain why the business jet closed with my
friend and I so quickly.

Shadowing is certainly a possibility. I've also wondered if the amount
of radar interrogations can cause the same thing; e.g., where I fly in
SE Washington state, my transponder is triggered only 5-10 times a minute.

Rather than just relocating the antenna, you can get Zaon's dual antenna
option. That puts antennas top and bottom on the aircraft, essentially
eliminating all shadowing. It might be easier than moving one antenna to
the tail, but it's pricey at $280 for the option, plus two blade antennas.

--
Eric Greenwell - Washington State, USA
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