Frans, I dont believe I mentioned "gain", If i remember correctly, there was
much
conjecture over how effective and how "directional" an antenna of this type
would be
a while ago on the forum. I was simply posting what I have done, and my
observations
on how well it "appears" to work, even when the source of the transmission
is in the apparent
worst location, in an attempt to answer some of the questions raised.
For all I know the transmission qualities of the antenna I built will be
very poor, with very high
SWR that cannot be corrected making it totally useless , but not having a
comm radio I
can hook up to the antenna i wont know until I actually test it's transmit
qualities.
The whole thing took about 10 minutes to make, and cost about $5, maybe if
you have a radio
you can use you could make one and see if your results are simmilar to mine.
BTW the wire
I used for the loop is .7mm stainless 316 grade, from a MIG welder spool, I
fashioned "clamps"
to hold the wire from the brass inserts in an old light switch, that have
the screws in them.
I simply cut the co-axial cable to length stripped it back and soldered the
outer copper braid
to the outside of one of brass clamps, and the inner copper core to the
other brass clamp, and then
crimped the BNC connector on the other end of the cable. The stainless wire
can then just be slipped
into the brass clamp and the screws tightened. I did drill a small hole in
the end of one of the
brass clamps to allow the loop wire to pass right through, which should
allow easy adjustment
of the length of the loop to get the SWR as good as it can be.
I dont expect the be buying any avionics until my baby is ready to fly, so
if anyone has the time
and a radio to test this I would love to hear from them, on or off list.
craig
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