A question to the experts:
I have a 40M and an 80M 4 square, each has been up
6-7 years. They are both made of Rohn 25, and the
base of each vertical is elevated 15 feet. Thus, a
simple 1/4 wavelength 75 ohm phasing line won't
reach from the phasebox on the ground to the "base"
of each vertical.
When I built the 40M 4 square, the then owner of
Comtek told me to use a multiple of 1/4 wavelength
75 ohm coax (I think I have 3/4) so it would reach
between the box and base. A lot of coax, but it works
great.
When I built the 80M 4 square, the owner of DX
Engineering told me to just use equal lengths of 50
ohm coax to drop down from the elevated bases to the
ground, then hook up the 1/4 wavelength 75 ohm coax.
This also works great.
Now, I find one of the 40M 3/4 wave 75 ohm phasing
coaxes is destroyed. (A horse was implicated and
arrested). It is just 3 days before CWSS and I have no
way to get any 75 ohm coax.
Questions: Are these two feed methods equivilant?
I plan to feed the 40M like the 80M, all I would
have to do is cut the good 75 ohm into 1/4 wave
pieces, cut up some 50 ohm coax and solder a few
plugs. I guess I could elevate the 40M phasebox on
a pole and string 1/4 wave phasing lines to the
elevated bases, but the 50 ohm drop down line
method sure would be quicker.
Any ideas?
Thanks, Bill WB0O in northern North Dakota, 10 miles
south of VE4 land.
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