Two Good Days Spent with Quads
Of course I will be trying this next idea even if no newsgroup answer is
forthcoming: What happens if I tap off quad #1 on the side _opposite_
where I'm feeding it and connect quad #2 there? Wouldn't this additional
load reflect back to feed #1 and lower its impedance toward 50 ohms? I
don't know what feed #2 would be. Perhaps a jury-rig parallel line
calculated to be 100 ohms would do it. (# 10 AWG wires on 5 mm centers would
do it.) Phasing will be an issue.
[I probably don't have a suitable test environment to tell success from
failure.]
73,
"Sal"
It is easier and cheaper to do phasing/matching harnesses with open
wire. Make it, don't buy it. Considering that a 1/4 wave is only about
19 inches you can make experiments with whatever wire is handy using
popsicle sticks ("craft sticks" at the craft store) and masking
tapefor the spacers.
Make a field strength meter with a diode and dipole connected to a
multi meter. space it about 30 feet in front of the quad. While
transmitting verify the elements are all working by touching each
element with a screwdriver.
Operate the transmitter at lowest possible power.
Too much fancy equipment gets distracting.
John Ferrell W8CCW
"Life is easier if you learn to
plow around the stumps"
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