[Antennas] Dipole Suppression of Even-Ordered harmonics [was: 6 meter vertical folded dipole]

2002年1月15日 13:25:14 -0500

Let's explore this a bit, please? Does a dipole, and perhaps slightly
more so a folded-dipole, actually "reject" even-ordered TX harmonics
or does it partially suppress them by failing to radiate them very
efficiently?
I ask because it makes for an interesting relationship to certain
amplifier designs. I forget off-hand which does which but does
not the circuit selection in an amp (e.g. push-pull) lend to the
creation of even or odd harmonics?
If one then chose an amplifier design that favored even-ordered
harmonics one could only use that amp with a dipole and thus
compensate for some (how much?) of the garbage created by
the amp with careful antenna design rather than lossy and costly
filters.
Yes, no, maybe ... 73, doc KD4E
> I guess I was being a little picky, but the sentence literally said that
> the *folded dipole* in addition to other unique properties rejected
> even-ordered harmonics, implying that this was yet another property unique
> to the folded dipole.
>> Of course, the behavior of any dipole that you summarized is correct and
> well-known.
>> 72/73/oo, George W5YR - the Yellow Rose of Texas
>> Dave Shrader wrote:
> >
> > Don't all dipoles 'reject' even ordered harmonics? <grin>
> >
> > Actually, all center fed dipoles exhibit an impedance variation from
> > 'low-Z' at odd ordered, relative to 1/2 WL, harmonics and 'high-Z' at
> > even ordered harmonics. Maybe this statement refers to the 'high-Z'
> > state as 'rejecting even ordered harmonics'.