I don't generally thermal in the mid to upper flight levels, so airliners
generally aren't a worry. When they're on descent into the Albuquerque
area, they're under the control of Center and Approach. The Feds see me as
well and provide a pointer to the airliners in the event they don't see me.
I periodically call Approach for a transponder check to verify that they see
me. They do.

As to two transponder antennae, I recall from my military days an antenna
switch. It was labelled, Upper-Both-Lower. It was always left in the Both
position. The transponder electronics sensed which antenna was receiving
interrogations and replied on that antenna. Sometimes I flew up side
down...


"kirk.stant" wrote in message
...
If your concern is being seen by airliners with TCAS, wouldn't' a position
on top of the fuselage be at least as good or better during cruise?

While circling, either would be about the same.

Kirk
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