Whenever these statements that say a vertically polarized (single
element) antenna is just as good as some sort of yagi (usually 2
elements and horizontal) appear, they almost always leave out one or
two key points. Firstly, "just as good" is usually defined in terms
of signal strength at the other end of the circuit. Well, almost any
antenna can be made to be just as good in that sense, if you ram
enough power into it. But, after falling for this statement myself,
and putting up a vertical for the high bands, and expecting to enjoy
them with measure equal to my buddies who all have up 2 or 3 element
yagis, it became obvious, especially during the sunspot minimum, that
they're having a lot more fun. Why? Because of what these "just as
good" statements leave out--that these guys with yagis are _hearing_ a
heck of a lot more than I am.
Those horizontal dipoles with parasitic elements up even only 30 feet,
make way better rx antennas than any noise pickup vertical ever will
and hearing the other guy is half the battle. Oh, you could put up a
vertical, feed it with 1.5 kw and put up a separate low noise rx
antenna, but if you are going to go to all that trouble, you may as
well put up a 2 el. quad (10 foot turning radius on the high bands)
which is almost like a glorified rx loop anyway, _and use it to
transmit_.
Okay, so why do all the low band hams use verticals? Purely
economics. For most, phased verticals on 80 and 160 are the only
affordable (in a relative sense) way to achieve any gain, and then, a
separate rx antenna is a must.
73
Rob / k5uj
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