Jamie, here is a quick update.? I got the WA3TFS amp kit built.? I went through the bias adjustment, all seems well.? After adjusting the bias, I applied +5V to the junction of C17 and R6 (as WA3TFS suggested) with my bench power supply.? As expected, the amp went into transmit.? The current draw was only 1mA.? This is encouraging as I should be able to simply send the QMX PPT-P to this point in the amp.
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I am setting up to do more tests with RF in from the QMX trying to reproduce your results.? Then I will repeat the +5V injection to R6 with RF in and measure the current draw under more realistic operating conditions.
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73,
Jim - AE5JE
AE5JE - Jim