Where does this small amount of energy that gets re-reflected come from?
A mis-adjusted tuner?
The conjugate match is a condition where impedances on both sides of the
junction have identical resistive components and reactive components that
are equal in magnitude but opposite in sign. This means the result at
the tuner is a purely resistive termination of the proper impedance. So
where does this "small amount of re-reflected energy that excapes the
antenna" come from? Unless im missing something (and that could be the
case) a purely resistive circuit of the proper impedance means unity so
all power is absorbed excluding the attenuation of the line.
When a tuner is properly adjusted to give conjugate match the tuner
generates a new reflected wave having the same magnitude but of opposite
phase of the reflected wave coming from the mis-matched antenna. The
waves are combined in the transmatch and a new wave of equal that is in
phase with the current and voltage is added to the source wave. This is
re-reflection gain. These in phase additions have the effect of
re-reflecting the voltages and currents into the forward direction
therefore completely cancelling the rearward traveling waves thus a 1:1
match is formed. No power is lost from the reflections and except for
the I2R and E2R losses in the tuner elements, maximum power is delivered
to the load. This is true weather the energy is being transmitted or its
a received signal coming from the antenna.
So again, where does this small amount of re-reflected receive energy
come from??
73 Chuck KR6C
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