[Elecraft] Fw: antennas for Susan

[Tom W8JI]

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An antenna is usually called by its ELECTRICAL properties, and if
tophats, loading, etc present current magnitudes and phases associated
with a halfwave, it will usually be called a halfwave.  Some will
refer to a halfwave with a lot of loading as a loaded or shortened
halfwave.>>

If we have a given height Marconi antenna, say 20 feet on 40 meters, the 
radiation resistance would be about 9 ohms. If we feed that same length 
antenna in a way to make it have a "halfwave" current pattern, radiation 
resistance is now 7.5 ohms.  The loading reactance at least doubles, so for 
the same Q loading system we have about half the bandwidth and twice the 
loss.

Loss is NOT proportional to bandwidth, they really are mostly independent 
characteristics when the system is changed.

This reminds me of CB antennas, where some crafty marketing person wound 3/4 
wave of wire in a six-foot space and told CBers it was a "3/4 wave helical" 
vertical with gain over a regular six-foot long helically wound vertical.

I hope we are not reverting to that level, but it seems we are!

73 Tom