I think the best vertical installations were done by old radio
engineers.
No modeling programs, but tedious solid measurements reflecting reality.
What I saw at WOO - Long Lines AT&T station is perhaps ideal setup for
vertical all band (discone) antennas.
Radiator sits on concrete base about 3 ft high, with insulator. Tower
radiator is about 30 ft high, with bundle of wires coming from the top,
to the ring about 2/3 up, then down back to base.
Not sure if there are any radials/screen at the ground, but the ground
is practically flooded by the sea water. Sea water comes through dredged
channels, with evaporation, I presume, increasing the salinity.
Radials are coming out from the base, suspended in the air, over to the
wooden circular "fence" (radius about 25 ft?) then they slope and drop
to the ground.
For better efficiency, it is desirable to make the high current carrying
portion of the antenna longest possible (electrical closer to 3/8 wave)
and portion of radials by the base suspended in the air (no earth
"eating" the RF). If no salt water, looks like the best combination is
to lay the ground screen in the vicinity of the antenna (gives
"reflections" for pattern forming) and then suspended or partially
suspended radials to "counterpoise" the antenna. No need to connect
screen to radials.
Best 160 inland vertical? Wally, W8LRL has 3/8 vertical radiator
sitting on the mound, with 360 radials 3/8 long, laid on the surface.
Looks like WOO Ocean gate QTH is (was) probably the best in the world. I
never seen the S-meter to sit at 0 on 160m on vertical, dead QUIET!
Yuri, K3BU.us
On Fri, Oct 19, 2018 at 08:58 PM, Guy Olinger K2AV wrote:
Quite late in response, partly done much earlier. Sometimes I have
time,
and sometimes I have a house and a spouse.
Peter's original question in this thread was why a radial and mesh mix
in a
counterpoise should have the radials and mesh bonded together. That is
quite a different question than why mesh at all, or how good is mesh
by
itself, or mesh versus radials, or just how does "ground" behave at
the
seashore.
.......
BL&E DID have VERY sensitive thermocouple field strength and power
measuring devices with exceptional accuracy. When I was employed by
AT&T
Long Lines in 1963, way back when I still had hair, variants of these
were
still employed for standard maintenance practices. They were
significantly
better than anything I myself have owned since. Just BULKY :>))
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