While Waiting for the placement of a 4-square receiving antenna, and the ground
to unfreeze here north of Chicago, I decided to put up a Flag Antenna. I used
the demensions of 14' vert. and 29 feet horizantal. I terminated the end with
a 950 Ohm resistor and used the W8JI, three stacked cores to bring the
Impedance down to 75 Ohms to match the flooded RG 6 coax. I actually measured
the impedance of 72 ohms and +3 XL, with an SWR of 1.2:1 and it stays constant
from 1.8 to 7.0 MHZ, (it may go higher in Frequency, but I did not check it
out.). The Flag is mounted 7 foot above the ground and points in around 225
degrees.
In this direction I do not hear Europe as Expected, and the signals that I do
Hear, mainly SA and the Pacific area are audible. Gain of Course is quite low.
So I do use a preamp, (DX Engineering), in the Shack and not out at the
Antenna. I do not have a choke on the COax cable going to the receiver as the
cable I am using is a flooded cable and fairly in-flexible.
I guess My expectations for this antenna are bigger than my actual experience
with it. Modeling shows a 30 degree take of angle, and about -37 DB Gain. But
I don't think I am hearing all that well with it.
Coax Cable is also routed out from the feed point Hozizantal for 20 feet before
dropping vertical, and it is not buried. Cable Length is 200 Feet.
I guess my question really is... Is this flag really playing like it should, or
am I expecting too much out of it?
BTW my Vertical is detuned during receive, and the Flag is outside the boundy
of the Radial wires of the Vertical..
Thanks for any assistance.
Bruce N9BX 73
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