Fixes to the EFHW Matchbox

I have decided to use the EFHW antenna as my primary portable antenna. My previous reports on this antenna have centered around testing on 20m which performed quite well. I want to set this up now for multi-band operation using connection links to add or remove wire as needed to tune it on a specific band. The capacitor I used tested between 9.5pF and 310pF which would let me operate between 40m and 10m. I was disappointed to find the matchbox would barely tune up 10m and would not come even close to 40m. I originally suspected stray capacitance and yes some did exist but what I found today solved the mystery. Turns out that I had connected to the wrong lug of the capacitor which limited the upper capacitance to around 100pF. I changed the connection point and am now able to tune down to 40m but have lost 12m and 10m as there is added capacitance on the low end as well. So my plan now is to run this match box on 40m, 20m, 17m and 15m which should be a pretty good range for this point in the solar cycle. The 40m half wave will be ~ 66 feet long so I’ll likely figure a way to configure that as either an inverted L or as an inverted V.  All other configurations will be as verticals. Next step is to cut a wire length for 15m then add wire to get to each of the successive bands. Band changes will require taking it up and down but it will be resonant. The backup antenna will be the end fed 9:1 matchbox and a tuner. Both will fit nicely into the soon to be reconfigured go-box.

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