I currently am completing construction of my first quad beam antenna. I
am looking for suggestions about how best to tune the elements. Here are
a few specifics about my system:
1) It is a 2-element, 5-band (10-20M).
2) Each element set (driven and reflector) are in the same plane.
System is using qubex mark2 spiders and spreaders.
3) System will switch between bands with the Ameritron RCS-8V remote
4) Upon Qubex's suggestion the 10,12,and 15 M bands will have 75 ohm,
1/4 wave, (RG11) matching stubs. They say stubs are not necessary for
17 and 20M.
5) The main feed will be 50 ohm triax (belden 9998).
6) At this point I have cut all ten elements extra long before I have
I did have the foresight to purchase the MFJ 259B ant. analyzer for just
this project. What I am guessing is that I should (one at a time) tune
each of the driven elements to resonance at mid-band point. It is at
this stage I'm not sure about the next step.
Q1) What is a good method to tune each of the five reflectors? I can
target a fixed frequency off-set from each of drivers (by percentage).
If so, what should the off-set be?? I'm not sure how to use the MFJ259B
to tune the F/B or Gain(max), if it can at all. I could use a field
strength meter but that's subject to error and my neighbors.
Q2) Is there a suggested order through the bands to be tuning either
the dir. or ref.? i.e.- 10>20 or 20>10?
Q3) And finally, any suggestions about what is a good method to secure
each of the loop ends to themselves and/or coax? I'm using the diamond
configuration that provides for a vertical spreader as an anchor point.
Thanks for input!
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