One seldom achieves the "advertised" or modeled pattern, especially at HF
frequencies. VHF, UHF, and ?waves are whole different stories. HF
patterns rarely conform to expected results except for installations done
by Uncle with unlimited budget (just us taxpayers!). So, don't sweat the
pattern modification. Even the "expected" pattern is likely not thereas
assumed.
And with only 28 dB isolation between the two antennas, disconnect one from
any receivers while transmitting on the other. 28 dB down from 100-watts
is still roughly 160 mW. I sure would not input that much power into any
receiver I own!
Dave - W?LEV
toggle quoted message
Show quoted text
On Sat, Jul 2, 2022 at 7:15 PM WB2UAQ <pschuch@...> wrote:
Did a coupling test between two antennas and it was interesting to see how
the impedance looking into one antenna was impacted when leaving one of
the antennas open, shorted and terminated in 50 ohms. With about 28 dB
between antennas I would see a change of a about 0.5 to 1 ohm. Could be
an indication of how one antenna impacts the radiation pattern of the
other. The energy reflected by one of the antennas is phase shifted by
180 degrees between a short and an open condition. At 28 dB of isolation
I bet there is little pattern change. Something to think about.
--
*Dave - W?LEV*
*Just Let Darwin Work*
--
Dave - W?LEV
