[TowerTalk] 16om vertical and the number of radials

[Lux, Jim]

On 12/2/22 11:32 AM, Richard (Rick) Karlquist wrote:
>
>
> On 12/2/2022 6:25 AM, Ignacy Misztal wrote:
>>
>> On the other hand, some really loud stations n 160m, say 5-10 db 
>> above the
>> crowd, use a massive amount of radials. This is for inland stations, far
>> away from salt water.
>
> I think this describes my station.  I do have a massive amount of 
> radials, and I am constantly told how strong my signal is.
> As to cause and effect:  I think not.  The real secret sauce at
> N6RK is the high conductivity ground, although the radials obviously
> don't hurt.  I am on the Sacramento river delta.  We have 100% clay
> going down 40 feet.


It's probably deeper than that.  The entire Central Valley is alluvium 
that's thousands of feet deep. In the delta, there's fresh loads of 
sediment every year (sort of.. there are levees), and there was an 
enormous amount in the late 1800s from hydraulic mining (as in hundreds 
of feet thick).



>
> Rick N6RK
>
>
>> Is there any discrepancy between modeling and real life performance with
>> the number of radials? Does adding radials beyond 32 help much? Any real
>> stories?
>
> The precise number of radials that is optimum depends on ground 
> conductivity.  N6LF's excellent work only strictly applies to HIS
> ground.  As for my ground, I suspect I could get away with only
> 8 or 16 radials. YMMV. 


And, it depends a bit on takeoff angle.  Broadcast AM is surface wave.  
But 160 is probably looking for skywave, so the soil properties quite a 
ways out have an effect on that. If you've got a 1 degree take off angle 
and a 40 meter tall antenna, the "reflection" of the top of the antenna 
is something like 2.2 km away