On 4/1/2021 6:40 PM, List Mail wrote:
An inverted-L should give you some better local station performance, which some
like to have for Contesting, as well as useful low-angle performance.
This is one of those urban myths with a grain of truth. The greatest
radiation is from the part of the antenna carrying the greatest current,
which for the inv-L is at the base. The grain of truth is that if it
isn't very tall (as a fraction of a quarter-wave), there will be more
current in more horizontal wire, increasing the high angle radiation.
In general,for ground-mounted vertical with a low feedpoint impedance,
efficiency is directly related to the ratio of the radiation resistance
to the effective resistance of the counterpoise, usually radials. And
radiation resistance is a function of vertical height.
The thing about antennas is that we're all limited by skyhooks, real
estate, sometimes other constraints like rules of a homeowner's ass'n. I
have many very tall trees and I can afford to hire climbers to rig
anything I want, so I have a Tee, about 100 ft.
73, Jim K9YC
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