Greetings,
I was digging in my tubing bone pile to make a 6M Dipole.
I came up with enough HyGain hardware scraps for 1/2" elements
and insulated element to boom bracket for same. I had a Balun Designs
balun laying around rated to 54 MHz to feed the dipole.
The elements were cut to quarter lengths (234/F) plus a couple inches
for trim/tuning.
Using my AA-55 hand held analyzer I was surprised to see the antenna
resonant at 45 MHz.
I'm guessing the "antenna element" resonance has to include the straps
back to this balun?
Also there is ~2-3" of tube burried inside the plastic insulator
sandwiched in element to boom
bracket which probably looks more like a shunt cap to ground.
There is about ~4" of strap from the exposed element that connects the
Balun box.
Wondering if anyone has tried to model and/or build an assembly like
this?
Thinking about it some it looks more like a Delta match.
I did one 2" trim and it shifted the resonance to 47 MHz.
Another 3" should hit 50 Mhz but that means the actual radiators are
some 4-5% shorter than 234/f predicts.
Has anyone else experienced this extra shortening of a dipole or yagi
driver whe using an boxed 1: 1 current balun?
Thanks
Mike K9MK
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