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April 06, 2009


Jacques Fortin

Heard anything about the Smith Chart ?
This was already figured out on the '30s.
Speaking of the velocity factor, prove how it is related to the line's dielectric relative permittivity.

John D.

Of course! This is obviously the basis of the Smith Chart. This calculation is just a way of looking at the underlying fundamentals.

The key to this is that a transmission line has some specified characterisitc impedance and some particular capacitance per unit length from which the inductance per unit length is found.

Then taking unit lengths in very, very small bits yields a recursive calculation of presented impedance. If you keep track of the length itself, when the presented impedance again equals the load impedance, that length yields the velocity factor.

electrical transmission lines

Electrical Transmission Lines are designed to hold up in adverse weather conditions, the transmission lines primarily use ACSR conductors.

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