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Old February 20th 07, 06:52 PM posted to rec.radio.cb
james james is offline
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First recorded activity by RadioBanter: Sep 2006
Posts: 298
Default Cobra 2010 loses Tx audio

On Mon, 19 Feb 2007 22:52:40 -0800, Frank Gilliland
wrote:

+++Notwithstanding the fact that the non-reactive component of impedance
+++changes at or near resonance, maximum power transfer (due to matched
+++impedances) occurs regardless of whether those impedances are reactive
+++or not. Hence "impedance match" instead of the more limited "conjugate
+++match". As for your assertion that non-reactive impedances are rare in
+++the "real world", maybe you should describe -your- "real world" and
+++how it differs from the rest of reality.


**********
I am not saying that the real portion of impendances are rare. I am
saying that pure resistance is but a subset of complex impedance. Pure
resistance is where the reactive part of the complex impedance is
zero. In the real world no component has a "zero" reactive component
as does it not have zero resistive part.

In conjugate matching, the nodal point where the output of the
transform network terminates with the load will have a net reactance
of zero. The real part is still there. It does not go away. The net
real part should be half that of the real part of the load.

All components have complex impedances. In cases where frequency of
operation is well below the self resonance frequency, discrete passive
components can be thought of as purely resistive or purely reactive
dending on construction of the passive part. That be whether it is a
resistor or a capacitor or inductor. Non passive components have
complex impedances.

All the above is valid only when you are dealing with time varying
signals. Complex impedance has no definition when dealing with a non
time varying signal(ie. DC).

james