> Terry, if you can change the Inverted "L" to a balanced "T"
> configuration you
> will see significant reduction of wasted radiation at high
> angles,regardlessof the support height senarios mentioned. In
> most cases the moving of the
> vertical drop wire portion exactly in the center of the
> horizontal portion,
> and with a modest radial system, will give you much better DX
> performance. In
> fact I have never heard of a single case where an inverted "L"
> will outperform
> the classic Marconi "T" for topband DX purposes.
>
> 73,
>
> Herb Schoenbohm, KV4FZ
I don't think you "waste radiation" with L top loading. You simply add
horizontal component and polarization to your signal, which could be beneficial
on transmit, if you want to cover near and far area (V+H pol.).
By using T loading, you "waste radiation" in the same manner, just that the
portion of current in the top of the T is split and then cancels out.
The net result is that it "forces" radiator to behave more like pure vertical
(polarization and angles). This could be beneficial on receive, when wanting to
reduce near signals and horizontal pickup.
Looking at the picture of current distribution in EZNEC model shows that the
current in the radiator would be the same in both cases and in the top loading
with L or T is either all (corresponding portion) radiated (horizontal in L) or
cancelled (in balanced T).
Yuri, K3BU
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