Transmission Line = Antenna
Take a close-wound wire helix of diameter D metres and having N = 500 turns
per meter. Wire diameter approx 2mm.
All formulae available from Terman, Kraus, ARRL, etc., etc.
C = 55.5 / (Ln( 2 * H / D ) - 1) picofarads per meter.
L = Square( N * Pi * D ) / 10 microhenrys per meter.
TransLine impedance, Zo = Sqrt( L / C ) ohms.
Propagation Velocity = 1 / Sqrt( L * C ) metres per second.
Take a length of H =1.5 metres of this helix and use it as a short vertical
antenna above a good ground.
It will resonate as a 1/4-wave vertical at 3.5 MHz.
Zo = 3243 ohms.
Velocity factor = 0.0701
Radiation Resistance = 0.176 ohms.
etc., etc.,
It's so simple you can't believe it. ;o)
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Reg.
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