----- Original Message -----
From: "Tom W8JI" <w8ji@w8ji.com>
To: <topband@contesting.com>
Sent: Saturday, August 11, 2012 11:43 AM
Subject: Re: Topband: RX 4 SQ Phasing
>> ** That doesnt make sense since the books, etc claim virtually no
>> directivity at a 1/4 wave. At 175 KHz a 1/4 wave is 1406'.
>
>
> I don't know what "books, etc" that comes from, but even over fairly good
> soil a 600-foot "Beverage" models to have about 18 dB side null and a few
> dB
> F/B at 175 kHz.
This for instance
http://www.aytechnologies.com/TechData/ShortBev.htm
>It isn't in "Beverage mode", but it is in a mode that offers
> directivity.
>
> They work that way, too.
And what mode is that? Yes they work suprisingly well at LF, so well in fact
that I can seperate stations on the same frequency, NDB's or the LF BCB.
> Certainly they are not good antennas in comparison to something full size,
> and are not acting as a Beverage, but they do have pronounced directivity
> at
> lower wave angles.
At LF its not much different than a BOG on 160 and its obvious that no
pattern reversal takes place.
Prior to these antennas the 175' Slinky also had good directivity on LF.
Ive seen no models that explain this.
>
> This is why people should never give up, and should experiment with the
> best
> they can do. Even if it doesn't work close to right, it can make people
> happy.
>
> 73 Tom
Thats always been my starting point, try it, then understand why, and then
improve it.
Carl
KM1H
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