Topband: SSW propagation on 160m

[Tom Rauch]

K3NA:
>and do not know how the operators were determining bearings.

KH6O:
> I've been wondering that myself. Are you folks using a DF loop
> or an Adcock antenna to determine bearings? A loop would be
> subject to error, wouldn't it?

It certainly is valid to question minor lobe response from some 
antennas, but I don't think that is the cause of skewed signals.

I use multiple arrays that are very well separated, with very low 
minor lobe response. For example my eight vertical array has a 
HPBW of less than 60 degrees, and the largest minor lobe is over 
25 dB down. The pattern is very clean, and there is little if any very 
high angle response in any direction. My arrays are well separated 
from transmitting antennas or sources of re-radiation.

By combining arrays, and nulling the signal, they can indicate 
direction within a few degrees under conditions of normal 
propagation. From Georgia, I can resolve the difference between 
two stations in New England that are only a hundred miles off line. 

With that in mind, I absolutely never find a time when the vertical 
arrays or combined arrays disagree with a single Beverage. That 
makes me almost perfectly confident that reports of general path 
directions from a station with multiple properly installed Beverages 
would with great certainty get the quadrant correct. 

Questioning the arrays is valid, but it is without doubt a dead-end 
road when the antennas are properly installed. I think the reports 
most of the serious DX'ers are reliable, since most of them pay 
great attention to proper receiving antenna construction.

73, Tom W8JI
w8ji@contesting.com


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