>1.) A resistor has inductance
>2.) This inductance is created by the resistive material as well as lead
>lengths
>3.) Therefore it is also an inductor as well as a resistor
>4.) Since it is an inductor it will have a self resonant frequency.
>5.) Since it has a self resonant frequency, it will create resonances.
A theoretical resistor doesn't have resonances. While we're talking theory
and practice, it might be a good idea to prevent confusion to say when we're
talking theory, and when we're talking real world.
A practical resistor has a resonance (one or more) because of its inherent
inductance and CAPACITANCE - inductance and resistance alone can't resonate.
If the inherent inductance of the resistor has at any frequency a reactance
equal to the resistance, then the Q must be 1 at that frequency.
At higher frequencies Q may be greater than 1 - depending on the stray
capacity of the resistor. If Q = 1, what does resonance mean, other than V
and I are in phase? Incidentally, it may be necessary as this discussion
develops to decide which of the 5 definitions of parallel resonance we all
adopt.
73
Peter G3RZP
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