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Years ago our local amp builder / pill stacker was making a similar argument to his customers that had radios with variable power. He said there was no need to reduce the carrier in an attempt to stop the Bird from flying backwards. He immediately made the connection that since the output impedance was being changed at the radio through the variable carrier, this was causing the reflected power on the output of his amps to sky rocket. That was a lot easier then admitting his amps were junk.

He had no desire to understand he was partly correct in that the output impedance would change but incorrect that alone would have any bearing on reflected power from the load. Reflected power is a function of the load impedance, not the source impedance. The only time the source impedance becomes an important factor is when it's operated at it's full rated power. Then it's critical due to heat dissipation and efficiency that the source match the 50 ohm load. For the device to produce less then full rated power it must increase it's output impedance and that's A-OK.

<blockquote data-quote="Shockwave" data-source="post: 251874" data-attributes="member: 10882">Years ago our local amp builder / pill stacker was making a similar argument to his customers that had radios with variable power. He said there was no need to reduce the carrier in an attempt to stop the Bird from flying backwards. He immediately made the connection that since the output impedance was being changed at the radio through the variable carrier, this was causing the reflected power on the output of his amps to sky rocket. That was a lot easier then admitting his amps were junk.He had no desire to understand he was partly correct in that the output impedance would change but incorrect that alone would have any bearing on reflected power from the load. Reflected power is a function of the load impedance, not the source impedance. The only time the source impedance becomes an important factor is when it&#039;s operated at it&#039;s full rated power. Then it&#039;s critical due to heat dissipation and efficiency that the source match the 50 ohm load. For the device to produce less then full rated power it must increase it&#039;s output impedance and that&#039;s A-OK.</blockquote>

[QUOTE="Shockwave, post: 251874, member: 10882"] Years ago our local amp builder / pill stacker was making a similar argument to his customers that had radios with variable power. He said there was no need to reduce the carrier in an attempt to stop the Bird from flying backwards. He immediately made the connection that since the output impedance was being changed at the radio through the variable carrier, this was causing the reflected power on the output of his amps to sky rocket. That was a lot easier then admitting his amps were junk. He had no desire to understand he was partly correct in that the output impedance would change but incorrect that alone would have any bearing on reflected power from the load. Reflected power is a function of the load impedance, not the source impedance. The only time the source impedance becomes an important factor is when it's operated at it's full rated power. Then it's critical due to heat dissipation and efficiency that the source match the 50 ohm load. For the device to produce less then full rated power it must increase it's output impedance and that's A-OK. [/QUOTE]

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