Fellow topbanders....
I've been looking at doing a couple of phased verticals and looked at a few
patents tonight on the US patent office web site. There is a reference to a
goniometer on page 14-6 of the "Antenna Book" (c 1994 by ARRL) and several
patents for RDFing use them to phase the antennas to give directivity (they
are very old patents--circa WWII).
After doing a bunch of searching my literature and the web, nothing. It
seems to me to be a perfect approach to inserting a phase delay to phase
antennas in a favored direction. So little information appears available.
Anybody got experience with these animals?
For those that don't have the reference, the basic design is to insert three
coils, one inside the other. Two are 90 degrees apart and fixed in
position. The third is rotatable to obtain a delay (apparently). Each coil
is inserted one inside the other. A couple of the US patents also make
reference to similar functions but use ferrite or iron powder (instead of
air coils) to solve the same problem.
I also (once upon a time in a galaxy far-far away) owned an Johnson Matchbox
that had a device that appeared very similar to tune the xmitter to the
antenna. I remember looking inside, seeing it, and wonder: "what the hell
is that!" That was 25 years ago but it maybe a clue as to their design.
If there are other references out there, I'd love to hear about them.
Ford-N0FP
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