If you want that you can look at the Waller versions which stack two antennas.
N4IS is the guru.
But everyone is describing a very small version of the terminated loops here.
2 by 2 meters is crazy small. I have experimented a great deal with these
small loops when K6SE came up with the concept. They have perfect cardiod
patterns just like the full sized models BUT negative 45 db "gain" is fairly
useless for DX. It's fine for BCB or more local work but the bare minimum for
any DX performance would be a half sized pennant. That's 15 ft by 7. I'd only
use that if you are in a very quiet area too as the output is quite low and a
preamp would pull in too much local noise if you have it. A tiny loop like the
2 meter squAre is better than a magnetic loop of the same size though. Unless
you have a strong point source of noise you need to null which is where the mag
loop would work out.
There is no sense at all in trying to deepen the rear null. 35db null depth
plus is pretty significant in any size.
Im starting to compare a half size pennant now pointing to VK from here with a
Short bog. Something less than 150 ft. long. So far casual observations are
showing significantly greater output from the bog but I need to do more careful
and controlled observations. The half pennant is too low in output for the
very weak signals I am experiencing here. I've used the half quite well to
Europe for 160 however.
Sent from my iPad
On Nov 29, 2011, at 21:25, Arthur Delibert <radio75a3@msn.com> wrote:
>
> I was wondering whether it might produce a narrower pattern in the front, or
> a deeper null off the back, or maybe even both. But indications from two
> people who have either modeled it or built it are that it requires 3 load
> resistors, one in each leg, and produces a highly reactive antenna with only
> a slight increase in gain.
>
> Clearly better and simpler to add a second antenna and connect them through a
> phasing device to null the unwanted stations, as described by Mark Connelly,
> WA1ION.
>
> ----------------------------------------
>> From: w2pm@aol.com
>> Date: Mon, 28 Nov 2011 21:49:40 -0500
>> To: radio75a3@msn.com
>> CC: topband@contesting.com
>> Subject: Re: Topband: Flag/Pennant Question
>>
>> Why would you do that?
>>
>> Sent from my iPhone
>>
>> On Nov 27, 2011, at 8:59 PM, Arthur Delibert <radio75a3@msn.com> wrote:
>>
>>>
>>> I'm wondering if anyone has ever built or modeled a multi-turn flag or
>>> pennant antenna. I'm thinking maybe an odd number of turns with the
>>> resistor in the middle of the middle turn.
>>>
>>> Thanks.
>>>
>>> --Art Delibert, KB3FJO
>>> _______________________________________________
>>> UR RST IS ... ... ..9 QSB QSB - hw? BK
>> _______________________________________________
>> UR RST IS ... ... ..9 QSB QSB - hw? BK
_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK
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