[TowerTalk] Aircraft Glideslope Antenna

[n0tt1 at juno.com]

Hi Gents,

A fellow ham uses a antenna, similar to this one, mounted on his car, 
to locate sources of powerline RFI.  (Actually, the one he uses is way
below.)

http://www.sea-avionics.com/lc/cart.php?target=productDetails&model=DMN25
-3&substring=&mode=research

The description says it's a grounded, center-fed loop.  I'm
guessing that the feedline is a length of coax connected across the
"molded dielectric", and that the opposite side of the loop
is electrically completed by the mounting, and is grounded to the
aircraft
at that point.  Is that correct or...?
_..._

Now this one has a "forward directional" pattern.  The description
says it is a folded dipole antenna and is intended for use
with two receivers.  If it IS a dipole, I don't quite understand this
particular configuration:  'Splain that please.  :D)

http://www.trast-aero.com/eng/catalog/view.php?ModelId=150

and here for a better photo and more info:

http://www.edmo.com/index.php?module=products&func=display&prod_id=10241&
disp=spec&cat_id=410

73 and thanks,
Charlie, N0TT