[TowerTalk] Shunt Fed Towers

[w8ji.tom]

Hi Jim and all,

> Load the 90' tower as a Conical Monopole for superior efficiency Vs
> shunt-fed.

The efficiency of a conical monopole and a shunt or series fed tower are
identical except for a very slight reduction in resistive losses in the
antenna conductors. Those losses are, in virtually every case, an extremely
small part of system losses. The conical monopole or a large multiconductor
skirt does give more bandwidth, and a true conical monopole is useful on
many bands without tuning. 

I'm sure you know this Jim, but I just wanted to point out that adding
skirt wires or folding an element does not reduce ground losses or increase
efficiency. 

Bill Orr and others (even one vertical manufacturer) have the strange
notion raising the impedance the coax "sees" somehow reduces ground loss.

That is pure bull.... excuse me.. incorrect. The net current flowing in the
ground is the same with either shunt fed, series fed, or multiwire skirts
for a given radiator size, and ground losses are identical.

73 Tom

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