Transponders will also reply to TCAS interrogations, even when out of ATC
radar range. Putting the glider in a metal hangar or glider trailer should
adequately "shield" the transponder. If it replies then, I'd think you have
a problem. Easy approach would be to just fly with it for awhile and see if
it returns to the behavior you expect (g).

bumper
"Gary Evans" wrote in message
...
Mine only responds to ATC queries, which increase or
decrease in relation to distance. If yours sends replies
when out of ATC range I would suspect the unit.


At 08:54 17 July 2005, Ian wrote:
Hi

A question for those who fly with Becker 4401-1 transponders.

Normally the 'Reply Indicator' triangle on the display
of our transponder
flashes briefly when the unit is interrogated, but
otherwise it remains
off.

Today I noticed today that it was displayed continuously.
This was
when I was at low altitude and the transponder was
shielded from ATC
radar by a mountain. When I climbed higher it seemed
to behave more
normally, but still displayed for several seconds on
some occasions.

Is this normal behavior for this unit that I have just
not noticed before,
or has ours developed some kind of fault?

I can't help thinking that a continuously 'Reply Indicator'
implies
continues transmission, which can't be healthy.

Thanks

Ian