Hi everyone, I have an inverted L on 160 with 15 mts of vertical side over a
good ground. It measures Rin 15 ohms.
I am planning to install another one a 1/4 wave away and phase them with 90
degrees difference looking for gain in broad angle rather than good f/B ratio.
I have no previous experience on phasing arrays. Reading ARRL antenna book and
ON4UN book, I am a little confuse about how to proceed in using coaxial as
phasing lines.
I wonder what could be better:
1 - Make the elements longer and use a capacitor to adapt them to 50 ohms
individually with the other element disconnected, then measure the combined
element resultant Z with both elements coupled and start the phasing line
length calculation from that point (ON4UN SW), or
2 - Make the elements longer and use a capacitor to adapt them to 50 ohms
individually with the other element disconnected, and use 1/4 wave vertical
line length examples in ON4UN book of 90 - 70 - 90 or 84 - 71 - 84, or
3 - Measure the combined resultant Z without any Z transformation at the
antenna bases, and start the phasing line length calculation from that point.
As I am planning to use 9913, I think that without any Z transformation at
bases, I might have a higher SWR on phasing line with a little increase in
losses and even more phase shift.
Finally, as I will not have more than 20 mts of coaxial to the connection point
of the 2 verticals.
4 - Would it be better to do the final match to 50 at the phasing line input
point or at the shack end?
Any suggestion, practical recommendation or consideration will be highly
appreciated for this first attempt.
Many thanks in advance '73...... Eddy, LU2DKT
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