At 20:30 25 November 2004, Mark James Boyd wrote:

Another possibility is a radar reflector installed
in the glider.
These things are much cheaper than a transponder, and
would give at least
some info...

I'd love to see if my local boating supply shop has
one that would fit
--

------------+
Mark J. Boyd

Boating stores sell radar reflectors made of cardboard
and covered with aluminum foil. They are in three
parts and can be disassembled. When put together they
make a sphere about 12-14 inches across and they provide
the 3D right triangles that are supposed to reflect
a signal back.

I inquired about their use in gliders (practically
no weight and could go in fuselage behind wing) and
someone told me they would not give a strong enough
signal for aircraft use owing to the speeds involved.
I have no idea about the validity of this statement.
Couldn't hurt to try it.