I take your point Yuri, but my simplistic way of looking at the current
decreasing along a straight quarter wave of wire is due to the current flow
through it's distributed capacitance to ground. Maybe that is wrong and I
should go back and look at my transmission line theory.
Surely the fact that it is an electrical quarter wave is due to the straight
wire being part of one very large coil turn and therefore having an inductance,
combined with that distributed capacitance causing resonance at one particular
frequency? If that is so, then isn't my theory of the current decay being due
to flow through distributed capacitance along it's length still correct?
AA7JV said that the argument against current at both ends of the loading coil
being the same, is that you cannot have high current and high voltage at the
top of the coil because that represents much higher power than you are sticking
into the base of the antenna. That's not true because we are talking about VA
not Watts, i.e. there is a phase difference between V and I.
73
Tom G3OLB
<He is not correct!
<Have you looked at the "piece" of wire - quarter wave antenna, having the max
current at the base and ZERO at the tip? And voltage low at the base and high
at <the tip - corona?
<Where did the current go?
<It is the STANDING WAVE circuit, with superimposed forward and reflected RF
currents creating cosinusoidal distribution ALONG the wire and not the DC
<circuit.
<Why is it hard so understand that if current can vary along the straight wire,
it can wary along the coiled wire too?
<Yuri K3BU.us
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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