Thanks, JC. Based on what you said and what I know about the location, I
think I probably have enough noise that I shouldn't have to worry about how
much gain the preamp might have relative to the negative gain of the
smaller antenna.
My plan would be to install it horizontally at about 64 feet above a
tribander. If I can make it all work, it would be the greatest improvement
to my little station that could possibly be made. I have worked VU2 and
some other good stuff with what I have tried in the past, but there is no
question that I transmit a lot better than I receive on 160m.
I see in the model I have that going to 750 feet high increases gain by
about 17 dB and RDF by about 3 as compared to where I can put it.
I would be very pleased to make a noticeable improvement over the little
triangle antenna and have something that is on my tower that I could rotate.
73...Stan.
On Sat, Dec 15, 2018 at 2:04 PM <n4is@n4is.com> wrote:
> Hi Stan
>
> There are two very important numbers to consider, first is horizontal or
> vertical, the horizontal signal is zero at ground level and maximum at 1.5
> wave length height , vertical signal is maximum at ground level and minimum
> at 1.5 wave high. The second is the gain, the local noise limits the gain,
> if you are on a very quiet location bigger loops can dig weaker signal out
> of the noise.
>
> Vertical WF can be small, 6 or 8m are common, you only need a low noise
> preamplifier 2db or better, gain is not important , 20 db external gain is
> enough on 160m. Horizontal is more challenging you need a < 1db NF.
>
> I am working on a project using two SDR receivers to phase the loops by
> software, it should be possible to reduce the size of the boom. But not the
> height necessary because the limitation is the horizontal receiver signal
> intensity. For horizontal average performance on 160m it is necessary 20 m
> above the ground, 10m high for 80m. Good performance on 160m it is
> necessary
> 30 to 40 m above ground, and it shows no limitation on performance. Higher
> is always better.
>
> Check vertical W8VVW (8m) WF or WX4D ( 10m) original WF.
>
> Regards
> JC
> N4IS
>
>
>
> -----Original Message-----
> From: Topband <topband-bounces@contesting.com> On Behalf Of Stan Stockton
> Sent: Saturday, December 15, 2018 2:15 PM
> To: topband@contesting.com
> Subject: Topband: Waller Flag
>
> I am curious to know if anyone on here has scaled a Waller Flag to a
> smaller
> antenna and had any success with whatever might be available for preamps to
> bring the gain up enough to start to hear band noise.
>
> At my location on Cayman Brac I could probably get by with a 20 foot boom
> but not much larger. According to my model, one with a 50 foot boom is
> about -48 dB, one with a 30 foot boom is about -65 dB and one with a 20
> foot
> boom, like I would lilke to put up, is about -79 dB.
>
> I guess a lot to do with how successful the antenna might work for me will
> have to do with how much preamplifier gain I will need at my particular
> location to start to hear noise. I wanna use it on 160, 80 and 40 and the
> gain of the 20 foot boom one is enough for 80 and 40 using a 30 or 40 dB
> preamp.
>
> Any help would be appreciated.
>
> 73 and Merry Christmas...Stan, K5GO/ZF9CW _________________ Searchable
> Archives: http://www.contesting.com/_topband - Topband Reflector
>
>
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