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I had it tuned pretty close with the 1/4wave cone Eddie,

not having my analyser to use i recalled the ARRL open sleeve antenna article i posted about years ago,
i presumed extending the radials & reducing the angle & spacing to the monopole would lower the feed-point impedance

i went looking for 50ohm a little higher up the monopole & found it,

I moved the gamma strap up in small increments & adjusted the gamma capacitor for lowest vswr each time until vswr was low again,

neither of them were tuned perfect but less than 1.2:1 on my old kenwood sw200a,

you can achieve a low vswr over a wide range of monopole and cone lengths.

[QUOTE="bob85, post: 752987, member: 18"] I had it tuned pretty close with the 1/4wave cone Eddie, not having my analyser to use i recalled the ARRL open sleeve antenna article i posted about years ago, i presumed extending the radials & reducing the angle & spacing to the monopole would lower the feed-point impedance i went looking for 50ohm a little higher up the monopole & found it, I moved the gamma strap up in small increments & adjusted the gamma capacitor for lowest vswr each time until vswr was low again, neither of them were tuned perfect but less than 1.2:1 on my old kenwood sw200a, you can achieve a low vswr over a wide range of monopole and cone lengths. [/QUOTE]

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