P.S. One cool thing: As long as we're attenuating 14 dB or more, we can use the Pi Attenuator to match a Lo-Z outpu,t like that from many aircraft rigs, to the 50-Ohm input of the amp. Input-series-output 7-590-54 Ohms gives us 36 dB down down and you get to watch the Antenna Current meter swing ;-).