Even if the unfed slopers are not grounded by the switchbox,
there is some finite capacitance to ground through the length
of coax going between the unfed sloper and the switchbox
so the 'floating' condition is NOT really floating, but capacitively
coupled to the tower, assuming each wire is fed with coax
from the switchbox.
Tom N4KG
On Thu, 03 Jan 2002 Don Havlicek <n8de@thepoint.net> writes:
>
> Whether or not the unused slopers act as a counterpoise or not
> depends
> on the switching arrangement.
> If they are 'floating free', then you are right; however, if the
> unused
> slopers are electrically grounded to the tower at their
> 'feedpoints',
> then they DO act as 'counterpoises' [in reality, they are part of
> the
> 'tower side' of the sloper system].
> I used a 'sloper' system like this before they were called 'slopers'
> ..
> used the guywires for my tower, insulated at top and bottom, as a
> 4-wire
> array, with remote relay selection of any one or two of them as
> radiators.
> Using one gave me a 'sloper' system, with the other three 'grounded'
> to
> the tower, and using two of them gave me an 'inverted-V'
> configuration.
> Should mention that the guywires were each 66-feet long, and my
> feedline
> was 450-ohm open-wire line, fed through a Johnson Matchbox to my
> Viking
> I transmitter ... [shade of the 'GOOD OLD DAYS']
> Don
> N8DE
>
>
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