Johan Van de Velde,ON4ANT wrote:
>
> Hi there
> Being in the process of mounting a quad antenna with quite large
> dimensions
> i ran into something ..
> The quad has 3 el on 40m, and is gamma fed..
> while in mounting position, the bottom of the diamond shape is only 2 ft
> above ground
> the resonance is around 7200 khz with a 1.5 swr bandwith of 150 KHz..
>
> The quad goes up to 80ft (central point)..
> Will the resonance go up or down ????
> the loop lenght is cut to be resonant at 7040 KHz
> i know the ground plays a major role.. so resonance will change
> In definitif position the quad will be high up so i don't want to chance
> something to the loop lenght before i know (guess) which way resonance
> will go
Johan:
I'm no expert but my quad tunes w/ a lower SWR when closer to the ground
and goes up when I raise it. Unfortunately I have never taken the time
to write the difference's down.
If your's is from a manufactor I would give them a call and see what
they have to say.
Patrick Lynd (AC6YD)
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