Okay, here's where I could really use some help, fellas....
As some of you know, I finally got my antennas hung this past weekend. The
arrangement is:
Hy-Gain TH-11DX 11-element 10-12-15-17-20M yagi 1 ft above tower
M2 6M7 7-element 6M yagi 6.5 ft above tower
Cushcraft 40-2CD 2-element 40M yagi 13 ft above tower
The TH-11 was tuned for phone.
The 40-2CD was tuned for "high CW."
With the tower raised to 72 feet, all bands show good VSWR =except= both 12
and 40 are unacceptably high (2.8:1). Both bands dip to minimum SWR where
they are expected to, but that SWR is simply too high.
The TH-11 and 40-2CD are connected to a common feedline via an Ameritron
coax switch that -grounds- the unused antenna.
With a minimum 10 ft separation between the TH-11 and 40-2CD, the
Conventional Wisdom said there would not be any significant interaction.
Me thinks I am seeing an interaction.
Any thoughts? Words of wisdom? Words of condolence?! :)
73, Dick
--
Dick Flanagan W6OLD CFII Minden, Nevada DM09db (South of Reno)
Visit http://www.qsl.net/cvrc/
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