Although these are antenna statements, they are pertinent to
160m verticals
FACTS:
1. Radiation efficiency of an antenna is determined by;
Radiation resistance
Eff.=-----------------------------------------------------------------
Rad. resist.+Ground resist.+Tuning
Induct.resist.+Conductor loss+Equiv.Insul. loss
Ref:Laport, Radio Antenna Engineering
2. A radial ground system improves an antenna's efficiency
by minimizing Ground resistance. (Accepted)
3. Antenna resistance equals radiation resistance plus loss
resistance.
4. Under maximum power transfer, (loss resistance assumed
zero) radiation resistance equals terminating (input) resistance.
Ref 3 and 4: Kraus Antennas, p 42, First Edition.
5. Input impedance can be increased by 2 or more wires (N)
in parallel connected at their ends to produce an input
impedance N squared times the single wire antenna.
(Accepted)
SPECULATION:
If radiation resistance is the same as input resistance per
item 4 above, antenna efficiency can be increased
effectively by using multi-folded wire verticals, making
ground and other losses negligible factors.
If not true, what is wrong with that speculation?
Vy 73, Henry G. Elwell, Jr., N4UH
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