>R. L. Measures wrote>
>
>> >K7GCO wrote:
>> >
>> >I've run patterns of verticals with radials 10 or more WL long and it
>shows
>> >some promise. I have a location where I will be able to do that. Has
>anyone
>> >any experience with this?
>>
>> >N6RK wrote:
>> >I don't know what program you used, but I ran
>> >a bunch of simulations on NEC3-GS. The results
>> >are fairly discouraging. With 10 WL long radials,
>> >you need thousands to be effective.
>
>> Since the end-feed Z of a half-wave vertical is typically c.
>> 1000-ohms, even one 1/4 wave counterpoise makes a sufficient ground.
>> OTOH, with 1/4 wave verticals, which have a thirty-something ohm feed Z,
>> an extensive ground is needed.
>
>We're confusing two different issues. One is the
>ground radials as counterpoise, the other is
>ground radials to enhance low angle radiation.
>A half wave vertical requires virtually no
>radials to equal the gain of a 1/4 wave vertical
>with radials. However, with either vertical, it
>requires an impractically large ground plane to get
>substantial enhancement of low angle radiation.
// Is lower angle radiation better below 20m?
> ...
- R. L. Measures, 805.386.3734,AG6K, www.vcnet.com/measures.
end
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