This is a little complicated, so follow along if you are interested.... I have a 40 meter beam, and a rotatable, loaded, 80 meter dipole on the same mast, a few feet above the 40 meter beam. For year
Hi Steve, Yes. Feed the two antennas separately. Use a stub in the 80M feedline as detailed here to kill the harmonic of 80 on 40. http://k9yc.com/LocatingStubs.pdf and http://k9yc.com/StubPlacement.
Why is the dipole resonant at 3.8? Are you using it there or only on CW? Wes N7WS I have a 40 meter beam, and a rotatable, loaded, 80 meter dipole on the same mast, a few feet above the 40 meter be
The antennas are fed separately. The stub on the 80 meter dipole does kill the interaction to the 40 meter beam. However, the Z of the stub is around 1000 ohms 80 meters, so it affects the 80 meter d
It's used on CW and SSB. The loading coils in the matching network are shorted out by relays on SSB. 73, Steve, N2IC -- Why is the dipole resonant at 3.8? Are you using it there or only on CW? Wes N7
Then it's the wrong stub. See the link I posted. 73, Jim _______________________________________________ _______________________________________________ TowerTalk mailing list TowerTalk@contesting.co
Steve, Wes's question and your reply yields the key. You're switching the resonance of the antenna, but not the stub. Take a look at the plots in http://k9yc.com/Coax-Stubs.pdf which I did by point-b
Wes's question and your reply yields the key. You're switching the resonance of the antenna, but not the stub. Take a look at the plots in http://k9yc.com/Coax-Stubs.pdf which I did by point-by-poin
Okay, I'll think about this some more. Note to others commenting, Steve is worried about interaction between separately-fed antennas, not harmonic suppression. Wes N7WS 73, Steve, N2IC -- Why is the
I am curious what is the interaction on 40m? Can you see this in a model? When I lived near Chicago I had a 90+ft 80m dipole on the same boom as a homebrew 2el full sized 40m Yagi and they seemed to
Another possibility: It sounds like the stub is tuned for minimum impedance on 40. That may not be necessary. If you tune the stub for maximum impedance on 80, its impedance on 40 may still be low en