Hi everyone. I am in the process of building some new receive antennas
and have been modeling a number of choices .My Transmit antenna is a
full wave vertical loop 70 foot high and about 210 feet long .Currently
I have a pair of short (28 ' ) base loaded verticals toward EU phased
with a DX Engineering NCC-1 and one 550 foot beverage toward EU .They
both work fairly well toward EU ,I would rate them about the same . I
have been considering some type of circle array but it would be fairly
close to the loop ~ 175 ft. When I start modeling vertical receive
arrays the interaction is quite bad .I have been unable to come up with
a scheme to detune the loop from the shack ,the only way I have come up
with so far requires a relay at 2 points on the loop. Beverages in the
same area don't seem to be affected very much . I understand about the
need to limit the rf the receiver sees, I am just concerned about how to
limit the degradation of the receive array .
Question 1 Are receive arrays with active antennas less affected than
arrays with passive elements . I don't know how to model the active
antennas . Do you just put a high resistance load at the bottom of the
vertical to simulate the amplifier ?
Question 2 Is there a better way to detune the loop ?
Lastly am I too concerned about the interaction on receive antenna
performance ?
Thanks for you time .
Glenn WW4B
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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