I have posted several times on this reflector as I have slowly installed my
reversible Beverage antenna.
The antenna is 480ft long and runs in a NE – SW direction. All of the
components are made by DXEngineering and was, I believe, designed by Tom,
W8JI. It uses ladder line that is 5 feet off the ground for the antenna
and 75 Ohm coax for the feedline. The antenna is now essentially complete.
>From my shack, I have run several plots on the antenna using my AIM 4170
with Zo = 50 Ohms. (I have not attempted to calibrate the feedline)
Here is what I found over the entire *160M band*:
In the NE direction, the SWR slowly rises from 1.6 to 1.9, at 1.9MHz, and
back down to 1.6. The one resonant freq. is 1.8MHz. The return loss is
essentially constant and -12dB.
In the SW direction, the SWR is essentially constant at 1.8 to 1.92MHz and
then smoothly moves down to 1.3 at the top of the band.
*80M Band*
In the NE direction, the SWR starts at 1.9 and slowly reduces to 1.3 at
3.6MHz and then slowly increases back up to 1.9. There are 2 resonant
points: 3.6MHz and 3.9MHz. The return loss is -20dB at 3.6MHz.
In the SW direction, the SWR starts at 1.8, decreases to 1.2 at 3.6MHz,
increases again to 2.0 ant 3.8MHz and then lowers to 1.4 at the top of the
band. There are 2 resonant points: 3.6 and 3.8MHz. The return loss is
-22dB at the lowest SWR (3.6MHz).
*40M Band*
In the NE direction, the SWR starts at 1.9 and slowly decreases to 1.2 at
7.3MHz. There is 1 resonant point: 7.3MHz. The return loss is -22dB at
7.3MHz.
In the SW direction, the SWR starts at 1.9 and slowly decreases to 1.2, at
7.2MHz, and then climbs to 1.8 at the top of the band. There is 1 resonant
point at 7.2MHz. The return loss is -26dB at 7.2MHz.
Comments and observations would be greatly appreciated. Bascially, what I
am interested in hearing is whether this data looks similar to Beverages
constructed by others. In other words, does it seem to be working properly?
Thanks for your help.
73, Wayne KK6BT
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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