w8au@sssnet.com wrote:
> To those of you who have QST libraries.... look at the pre-WW2 schemes
> for feeding beams with open line.... our fathers and grandfathers were no
> dummies....
>
> At the antenna end of the open line you feed a fixed loop under the beam,
> and the beam then has a close spaced loop right above it... inductive
> coupling - and no problem with twisting feedlines....
>
> As the proverb goes, "nothing new under the sun"....
Another method used by the old-timers including R.O.S. Akre W4ZZZ (SK)
in Miami was to use a non-conducting disc on the mast below the yagi.
The disc has two concentric ring of brass or copper on the bottom side.
The feedline was brought up to two wipers which made contact with the
rings. A short length of open wire line from the yagi was connected to
the concentric rings. Voila!
Dave Heil K8MN
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