Quote:
Originally Posted by -.-. --.-[_2_]
All begin reading the advice of a reseller on a Italian ham magazine, that
claim this (translated):
"The MFJ 1796 antenna only at XXX euro !!! 2,6,10,15,20,40 meters Superior
Half-Wave configuration !!"
Oh well, i'm really a rookie on antenna theory, but - thinking into myself -
someone at MFJ can please explain me what the hell make on this antenna to
shrink an half wave antenna on 40 meters into a stick shorter than quarter
wave??
Before posting the question on this NG to learn more, a look on MFJ site and
i read on the description:
"Full size halfwave on 2/6 Meters."
Ah right, someone here in Italy forget to specify *where* is 1/2 wl designed
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The antenna is electrically a half wave on 10M to 40M, the electrical length of an element is not directly related to it's physical length. That is how they make a "halfwave" in a stick shorter than a physical quarter wave.
The line "full size halfwave on 2/6 meters" indicates that on those two bands the antenna is not loaded, but actually physically a halfwave antenna. The manual indicates that as initially built to dimension, before adjustment, the antenna is centered on 51 MHz on 6M, and 146 MHz on 2M, so my assumption s it is acutally a halfwave on those two freqs.