<< 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 ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
