My JK Mid 40 includes “shorty forty” that has low SWR in the CW subband on 40m but up to 3.0:1 at 7.2. That was not a problem when I used the Expert amplifier with the built-in tuner.
However I upgraded to the Flex combo of PG XL amp and TG XL tuner, and the tuner was broken. After sending a tuner back, I wondered how to make the SSB workable during CQ WW SSB. After measuring impedances at the base of the tower, it turned out that after shorting the cable with 500 pF capacitor, SWR would be <= 1.5 from 7.1 to 7.2. I made a remote switch, made it switch automatically with Green Heron software, and the arrangement worked very well in the contest.
Switching is by a miniature 250V/10A relay from a wireless remote control . No problem at the 1.5 KW level.
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