Can someone please shed some light on the definition of resonance in conjunction with an antenna.
Let's agree that "resonance occurs when +/- jX is zero".
It does not take knowledge of x-degree differential equation , modelling , size of wire , moon phase etc.
It is applicable to ANY AC circuit, antenna included.
Let's also agree that dipole , by definition resonant radiator, exhibits APPROXIMATELY 50 Ohms impedance
at the center feed point.
For a sake of simplification let's also agree that variation of the center point impedance with - insert your favorite parameter here - is not fundamental to the discussion .
Now for the punch line
By definition , ANY length of transmission line of characteristic impedance will transfer impedance at the load - AKA terminal impedance EQUAL of transmission line characvteristric impedance TO the input of such transmission line.
Place note - I am still using general terms, adding SPECIFICS - such as velocity factor of RG58 coax is immaterial - for the sake of this discussion.
Described ideal system ,for purpose of staying with basic, not woo-doo electronics , with "real data of 50 Ohms substituted " parameters of
source impedance of 50 Ohms ,
transmission line of characteristic impedance of 50 Ohms
and load / antenna impedance of 50 Ohms
will PRIMARILY exhibit FUNDAMENTAL resonance @ ONE frequency.
IF these parameters are SAME and EQUAL on harmonics , resonance @ harmonics will be observed.
So if the load (antenna) impedance at random frequency NO LONGER matches the transmission line characteristic impedance - everything else staying same , balum or no balum, you see the results.
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