[TenTec] OT: Openwire/Window Line and Bad Wx

[Richards]

On 8/3/2013 6:01 PM, John wrote:
> I hope this does not add to the confusion too much. However...
>
>   Radials really only apply to quarter-wave verticals.


	Well... er... um... not really.  You want a nice
	set of radials under an inverted-L antenna... and
	other designs, also.

	Bill Orr W6SAI (sk) says the folded unipole
	requires a radial system, as does the Folded
	Marconi antenna, and Extended Marconi, and
	his book, and the ARRL Antenna Compendiums
	have examples of various sloper antennas that
	employ ground radials.

	See Radio Amateur Antenna Handbook by Orr and
	Cowan, Radio Publications, Inc.

	A quick romp through HF Antennas for Everyone
	by Read, G1MFG, published by RSGB, shows many
	antenna designs that employ ground radials,
	including some dipole designs, for example
	the one depicted on p.43 that uses ground radials
	on a dipole with window line vertical segment.

	Just a few examples to illustrate ground radials
	are used on many designs other than 1/4 wave
	ground plane antennas.





A half-wave vertical only requires a ground.



	Er... Um... there is serious disagreement on this
	one, and many operators suggest a half wave
	vertical can realize substantial benefit from
	ground radials or a "counterpoise" - you can read
	one cogent argument for this here:

http://www.w8ji.com/end-fed_1_2_wave_matching_system_end%20feed.htm

	I think the gist of the argument is that it does
	need some sort of counterpoise, or else the
	choke balun must absorb all the return energy
	or else your feed line becomes the return path
	and acts as part of the antenna system.  But
	don't take my summary for it, W8JI does it way
	better without my help !  ;-)




Although I have not
> seem this, it would seem to me that for multi-band verticals, there
> should be some isolation of the radials in order to maintain the desired
> pattern for the upper bands.


	Interesting... what do you mean by Isolation?
	I am not being critical or funny here, but
	don't the radials still need to be connected?
	Not sure of the meaning of "isolated" in this
	context.


These points illustrate why I am fascinated by ham radio- there are so 
many facets, angles, and competing designs, ideas, etc., and so many 
apparently contradictory elements, it seems impossible to run out of 
things to research and learn about.  I don't intend to be contrary, but 
merely point out the complexity of it all, just using the above example 
of the use of radials on many designs beyond the ground plane.  There is 
no end to any of this!      ;-)


---------------- K8JHR -------------------