Phase lines
My first post here so please be patient. I have constructed a 3
element 40 meter quad at 1/8 WL spacing and have the front two
elements at equal length(7.18) and a rear parasitic reflector which I
resonated at about 7.5. I am driving the front two elements with a
reversed 3/8W/L, 135 degree phaseline. The question I have is
concerning an accurate method for obtaining the correct phaseline
length while using the mfj analyzer. I have been told that if the line
is shorted at the end I will read the frequency at which the line is
3/4 WL at max impedance. If that is a correct assumption than can I
look for the length that will read twice my target freq of 7.18
(14.36) ?.
I have it up and running and it appears to have substantial gain and
good front to back reference a EDZ at 3 times the height. I realize
the EDZ has gain in both directions but the Foreign Broadcast had
become unbearable most nights so hence back to the quad.
Tnx,
Bob N4JTE
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