Hi Mike,
> The reflected wave combines with the incident wave at the source
> such that the source sees a mismatched load.
I contend this is true when a conjugate (reactance cancellation) exists at
the source. Typically, this is accomplished by the ubiquitous transmatch,
auto-tuner or Pi-network within the transmitter. The degree of re-flection
and combining of the reflected wave with that of the forward wave is a
function of that network's ability to cancel system reactance.
In the case of a fixed, 50-ohm output transceiver (e.g., my Ten-Tec Omni
Six), I am observing that all reflected power is being returned back to, and
absorbed by, my transceiver when the transmitter is feeding an unterminated
line. This is major point of contention on this thread. When transmitting
into an unterminated 100-foot length length of transmission line, my Bird 43
displays 100-watts forward and very close to 100 watts reflected. Under
this condition, my transmitter draws 20-amperes DC at 13.8 volts. This is
not a trivial point. Watt's Law still applies: power is being generated and
dissipated. Notwithstanding any line loss power, the vast majority of that
power must be absorbed in the transmitter's PA. Thoughts on this point?
-Paul, W9AC
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