jim Jarvis wrote:
> I have seen K1WA's excellent article in the Antenna Handbook for years
> regarding sloping half-wave dipole arrays. His design switches both
> the center conductor and braid for each feedline.
>
> Is it really important to switch the braid?
> 73, Steve, K4FJ
> -0-
>
> YES.
>
> The K8UR sloper array design, and the variants upon that, require
> that the
> reflectors not be connected to the driven element. If you use a
> switch which
> ties all shields together, you'll have half of your reflectors and
> your driven element
> fed together.
That is why you install a choke/current balun on the feedline the proper
distance from the antenna. Then the shields can remain at DC ground
(for safety)
73
Roger (K8RI)
> God knows what pattern will result. Or, knowing
> this audience,
> only an adept NEC user with a lot of time will know what the
> resulting pattern
> will be.
>
> The technique of feeding each dipole via 3/8 lambda coax from the switch
> is a particularly neat way to assure that the undriven elements
> function as
> reflectors.
>
> N2EA
>
>
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