MJKTuck@cs.com wrote:
> ...
> I had the [fin mounted] Copper tape along the fin Europa supplied as the
> antenna.
> ...
> Bob Nukolls lives here in Wichita so he helped me out by taking a reading of
> how many watts my transmitter was pumping out. It was about 3 watts as I
> recall - not the 5 or so I should be getting....
I'm curious if Europa is supplying anything for a balun with the
copper tape antenna. Anyway, RST Engineering provides toroid cores,
appearing to be Amidon T-37-17 iron powder cores. At least same
blue/yellow and dimensions. Three are slid over the coax insulation
and RTV'd, just before shield is brought out to a pigtail. Spacing
unimportant, but 1/8"-1/4" OK.
Bob Archer says this is ineffective. Jim Weir of RST replies, bring
betting money to his RF lab.
> ...tried the Bob Archer antenna and it improved some. I decided to try a
> whip antenna mounted on the underside of the fuselage...could hear me
> 'fives'...
That sure sounds like the problem of proximity to metal radiating
elements when mounting inside the fuselage, like rudder operating
stuff vs. the fin mount. Copper tape (in free space) works just
fine. To tune my wing mounted nav antenna, I mocked it up on foam and
used the Nav on the other plane at the airport. A VOR 19 miles away is
scratchy and very weak, so that any weaker or less omnidirectional
reception compared to the known-good A/C's antenna would be easily
detected. On a simple 1/2 wave dipole with good balun, or 1/4 wave
whip, any purveyor claiming superiority, I believe is blowing smoke in
the sales brochure. Seems that problems arise in the installation.
Best,
Fred F.
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