On Sep 12, 6:57*am, Darryl Ramm wrote:
John Smith wrote:
Darryl Ramm wrote:
The TT-21 as a Transponder utterly blows away any other transponder
available in the USA for use in gliders.

Just be aware that the TT21 is a class 2 tansponder, i.e. not
certified for use above 15,000 feet, and therefore not suited for
gliders. Buy the TT22 instead which is class 1.

This has been discussed here a lot before. the *power difference will
make no practical difference. By all means pay slightly more and install
the TT22 but the important thing is for folks that fly in busy airspace
near airliners etc. to have a transponder (and even an older Mode C
transponder works fine fir that). Most transponders installed in gliders
in the USA appear to be class 2.

Darryl

The TT22 draws about 20 percent more power when transmitting than the
TT21. It's not a lot, but with PowerFlarm going in to my panel as well
I will end up with a 1.5 amp total current requirement, so I figure
every milliamp is worth saving. It seems odd to me that Trig didn't
design with the Class A floor as the break point between design
specs. Then again...

9B