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All I can say here is that I agree if there is an SWR mismatch shown on the meter then the reflected wave will see the transmitter as the load for that. But, if the load is representing a 50 ohm impedance to the meter it will not show reflected power regardless of the transmitter output impedance.

Stop debating and load a tube amp up at different impedances by using different loading values and redipping the plate. Once the meter is recalibrated you too will see you can't cause a objectionable change in reflected power by varying the output load impedance.

As Bob already pointed out the output impedance match of an amplifier is only going to be matched at a given value of drive, voltage and current. If your theory was correct driving an amplifier on SSB would cause severe shifts in the output SWR when in reality as long as the meter is calibrated for a given power the ratio of reflected changes little throughout the power range and changing output impedances.

The problem with the amplifier described was instability and oscillation. If there were a mismatch between the transistors and output it would not show up as a high SWR after the amp. You would need to measure that reflected power between the transistor and transformer. Not a simple task.

<blockquote data-quote="Shockwave" data-source="post: 198537" data-attributes="member: 10882">All I can say here is that I agree if there is an SWR mismatch shown on the meter then the reflected wave will see the transmitter as the load for that. But, if the load is representing a 50 ohm impedance to the meter it will not show reflected power regardless of the transmitter output impedance.Stop debating and load a tube amp up at different impedances by using different loading values and redipping the plate. Once the meter is recalibrated you too will see you can&#039;t cause a objectionable change in reflected power by varying the output load impedance.As Bob already pointed out the output impedance match of an amplifier is only going to be matched at a given value of drive, voltage and current. If your theory was correct driving an amplifier on SSB would cause severe shifts in the output SWR when in reality as long as the meter is calibrated for a given power the ratio of reflected changes little throughout the power range and changing output impedances.The problem with the amplifier described was instability and oscillation. If there were a mismatch between the transistors and output it would not show up as a high SWR after the amp. You would need to measure that reflected power between the transistor and transformer. Not a simple task.</blockquote>

[QUOTE="Shockwave, post: 198537, member: 10882"] All I can say here is that I agree if there is an SWR mismatch shown on the meter then the reflected wave will see the transmitter as the load for that. But, if the load is representing a 50 ohm impedance to the meter it will not show reflected power regardless of the transmitter output impedance. Stop debating and load a tube amp up at different impedances by using different loading values and redipping the plate. Once the meter is recalibrated you too will see you can't cause a objectionable change in reflected power by varying the output load impedance. As Bob already pointed out the output impedance match of an amplifier is only going to be matched at a given value of drive, voltage and current. If your theory was correct driving an amplifier on SSB would cause severe shifts in the output SWR when in reality as long as the meter is calibrated for a given power the ratio of reflected changes little throughout the power range and changing output impedances. The problem with the amplifier described was instability and oscillation. If there were a mismatch between the transistors and output it would not show up as a high SWR after the amp. You would need to measure that reflected power between the transistor and transformer. Not a simple task. [/QUOTE]

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