>Maybe easy, but decoupling is still necessary if you want a
>clean and reliable installation. The notion a few 1/4 wl
>radials result in a perfectly unbalanced antenna is clearly
>false.
>A commercial 40MHz groundplane using four 1/4 wl radials
>required significant choking (a few hundred ohms CM
>impedance) of the feed line shield *and* isolation of the
>radial common point to the mounting bracket. Without doing
>that common mode current was so bad SWR could change from
>1:1 to 2:1 just by altering the height of the supporting
>mast or length of the feed line. The problem also applies to
>160 meter verticals as well as UHF ground planes.
>With elevated radials near earth there can be a dB or more
>FS reduction when the feed line shield is not decoupled.
>Tom
My feed line choke is 24 turns of RG-8 on a 6 inch PVC pipe. It is located
right at the feed point, 60 ft. up the tower.
Is this sufficient, or do I need something more?
(((73)))
Phil, K5PC
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