Topband: Inverted L improvement question

[n4is at n4is.com]

Wes you're right

The SAL is a good antenna, any directivity increases signal to noise ratio. The RDF is 2 to 3 bd better than the vertical antenna, it means the improvement on signal to noise ratio is about 6db.  You can dig signals 6 db below noise with the SAL  that you cannot hear with the inverted L.

..but the SAL  has the same performance of a K9AY, or EWE or a single FLAG, The clamed 10 db RDF was never confirmed or measured, The SAL  is the most complicated K9AY you can build. The separation in two loops does not change the directivity. 

You can phase 2 FLAGS to increase RDF to 11.5 DB, as well you can phase two K9AY or 4  if you want, but the SAL phasing system is complicated and it is impractical to phase two SAL to increase RDF.

73
JC
N4IS
-----Original Message-----
From: Topband <topband-bounces at contesting.com> On Behalf Of Wes Stewart
Sent: Friday, December 28, 2018 10:50 AM
To: Arthur Delibert <radio75a3 at msn.com>; Jeff Woods <jmwooods at yahoo.com>
Cc: topband <topband at contesting.com>
Subject: Re: Topband: Inverted L improvement question

I was an early participant in the SAL yahoo group and introduced Dan, AC6LA, to the group.  He has provided a lot of modeling tools.

That said, I lost interest after feeling that the design was too complicated, not well understood and suffered from a dizzying number of changes.  I could be totally wrong about this, but that was my assessment some time ago and frankly I haven't kept up.

Wes  N7WS



On 12/27/2018 4:15 PM, Arthur Delibert wrote:
> You may also want to check out the SAL-12, -20 or -30 antennas from 
> Array Solutions.  My yard is pretty small, but I was able to put up a 
> SAL-12, and I love it.  (I do mostly 49-, 60- and 90-meter SWBC DX.)  
> I can switch the antenna to any one of 8 different directions, and I'm 
> often surprised to find that the DX is coming from a direction different from what I would expect.
> Often there's a very pronounced peak in the signal when the antenna is 
> pointed in the right direction, and I really would not have had any 
> copy if I couldn't point in that direction.
>
> The SAL-12 isn't especially good on 160, but is good from 3 MHz and 
> higher. The SAL-20 and -30 are reportedly very good on 160.  If I 
> recall right, the
> SAL-20 is directional up to 20 meters; the SAL-30 is good up to 40 
> meters. Check the Array Solutions website to confirm.
>
> These aren't as cheap as putting up your own pennant, but above 3 MHz, 
> the
> SAL-12 aimed NE almost always outperforms my pennant pointed in the 
> same direction.
>
> Regards,
> Art Delibert, KB3FJO
>
> ----------------------------------------------------------------------
> ----------

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