This antenna started out as a "U", but in trimming it back to
resonance (folded counterpoise plus isolation transformer plus antenna
length), the down part of the "U"s up, over and down got nearly
eliminated. There are four other stations using these who do not wish
to be identified, who have used the counterpoise for significant
improvements, but to my knowledge have not put up the antenna with all
the recent "refinements for cause".
On Wed, Nov 16, 2011 at 8:40 AM, W0UCE <w0uce@nc.rr.com> wrote:
> Top Banders:
>
> Further to Guy's report, N3ND's Inverted U Antenna is the third operational
> Top Band Antenna employing K2AV's Folded Counterpoise(FCP)versus raised or
> buried radials. The other two are Inverted Ls with FCPs at K2AV and W0UCE.
>
> After downsizing to a small QTH with limited space for a Top Band antenna I
> expected my Top Band days were over. Not the case... My inverted L vertical
> section is only 46.5' but results have been good to include working JA, ZL
> and VK. The same antenna is used on 80 meters with ten 25' buried copper
> radials and a matching network designed by Guy. Switching bands is
> accomplished using a vacuum relay at the feed point.
>
> Jack W0UCE
>
>
>
>> We are testing N3ND's new 160 antenna tonight (Monday local time) 1818
>> @ 0005Z. This is another antenna based on RBN validated untraditional
>> design. 73, Guy.
>
> To see the RBN, go to http://reversebeacon.net/srch.php
>
> Type in N3ND, hit enter. Look for the 160m spots around 03z 15 Nov. The 03z
> spots are at 400 watts. The 00z spots were at 100 watts, before the band
> was really open to the SE. RBN's from two other stations in the area were
> down by similar measure at 00z and up at 03z.
>
> This is an up 70, over 60, down 5 wire fed via a feedline isolation
> transformer against a 5/16 wave single wire folded counterpoise at 8 feet.
> No radials.
>
> There is no way his small lot property could support a dense radial field,
> either buried or elevated. Therefore, presuming that undense irregular
> radials that would fit would be excessively lossy, per RBN data previously
> gathered, the +33, -33 foot linear folded counterpoise
> (FCP) is used instead, elevated at 8 feet. The folds in the counterpoise
> are designed to self-cancel fields as much as possible, thereby minimizing
> ground induction, which is loss to skywave. The 66 foot straight line (more
> or less, not critical) FCP footprint is much easier to place on property
> than some miscellaneous attempt at a broadcast standard radial field.
>
> 73, Guy.
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
>
>
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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