In a message dated 98-07-31 00:50:50 EDT, K0HA writes:
>de K3BU: Majority of propagation on 160 is at around 30 - 45 deg angles.
(This is why quarter wave verticals play best - widest vertical angle
coverage)<
<< de K0AH: If this is true, why do the stations located on the edge of an
ocean (some of which you have operated from) have such an advantage?
The majority of the ocean enhancement is at the lower angles of
radiation (under 30 degrees). >>
Close to the ocean "the whole thing" gets a boost by about 10 dB (even
"coathanger" antenna). Yes, the better "ground" - salt water fills in and
enhances antenna pattern especially at low angles, which has lot to do with
the far field enhancement. So quarter wave vertical antennas close to salt
water gets full lobe from almost 0 deg to about 50 deg, while "dry land"
verticals or with less efficient ground plane have part of the pattern from 0
deg to abt 20 deg "erased".
(Makes you kinda sick to sit there (oceanfront) for 4 hours at the beginning
of Eu opening and not being able to work them. Just like licking honey through
the glass! But last time when I had also inverted Vee at abt 70 ft, I was able
to work them about hour earlier than with 4-square (!) - speaks for higher
angle propagation.)
When I drove my radiomobile (vertical whip ant.) to the fishing pier that
was sticking about 40 ft into the ocean, it was like driving into the
amplifier and QUIET!!
Now I believe in oceanfront QTH, but top of the hill still bugs me. Recent
return of OK2RZ and LZ2CJ to hilltop places indicates similar experiences as
with oceanfront enhancement on low bands.
Sooo, I am looking for the hill in the middle of the ocean (NP4A?). I am
hoping to finish my mobile/trailer setup, that I can take to different places
and take advantage of geographics.
73 Yuri K3BU/m, VE3BMV/1, Pee Forty Aaaaah
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