Topband: Phased Pennants: Staggered?

[olinger at bellsouth.net]

Right on, Tom.

Nearly repeating what Tom posted, beverages, pennants, et al are all about **NOT** HEARING WHAT YOU **DON'T** WANT TO HEAR.

That means you need to know WHERE what you DON'T want to hear COMES FROM. 

Listening to QRN on the band, I have been fascinated with the lightning strike web page, which shows me where the QRN is coming from. 

>From the location I can also infer angle.

When you model the combination antennas, use the 3D presentation and make sure you have your nulls aimed at the common sources of noise. That's **BOTH** azimuth and elevation you have to worry about. 

At my location, listening to Europe, one tends to think of 45 degrees as the proper angle for the gain, when in fact, 180 high angle is the best direction for the null. For a single pennant 45/225 is NOT the best orientation for the antenna at my QTH.

By the time the winter season starts to sneak up on us, the nastiest QRN is centered due south from NC, and only 500 miles away, in the Carribean.

So I need to plan the NULLS for Florida first. Then the Southwest. THEN make sure the gain is pointed somewhere up north, more or less. 

Think Signal-to-noise. You might be able to increase gain by 3 db and make a null 3 db deeper, that's a 6 db improvement IF the null is aimed at the noise. 

Or you might LOSE 2 db gain, and put 15 db MORE null toward an important noise source. That's a 13 db improvement. On 160 there's plenty of signal to drive lossy directive antennas. Design and aim the nulls first not the forward gain.

Sometimes I think hams have been completely hypnotized by forward gain and SWR. 

73, Guy.


> 
> From: "Tom Rauch" <w8ji at contesting.com>
> Date: 2003/11/10 Mon AM 09:10:44 EST
> To: <jmaass at columbus.rr.com>,  <k4ie at hotmail.com>, 
> 	"Earl W Cunningham" <k6se at juno.com>
> CC: topband at contesting.com
> Subject: Re: Topband: Phased Pennants: Staggered?
> 
> Hi All,
> 
> > Two endfire Pennants will narrow the cardioid pattern only slightly.  The
> > TOA will also lower slightly and, of course, there will be about 3 dB
> > gain over a single Pennant.  There is really little advantage for the
> > endfire Pennant configuration.
> 
> I respectfully disagree with Earl on this. It is like concluding making a
> Yagi longer does not or cannot increase gain or directivity. Pennants,
> Flags, K9AY loops, and EWE's are all really just two-element verticals with
> a very broad pattern and RDF about the same as any two-element array (the
> horizontal component of the wire makes them slightly less performance than a
> true vertical). Like a Yagi or any other end-fire array, directivity HAS to
> increase with length, and with proper phasing will be close to 3dB
> improvement with a doubling of array length.
> 
> The most common problem when people try to phase arrays is picking the wrong
> phase angle. Combining small array cells requires NOT placing a null where a
> null already exists, otherwise you gain nothing or very little. In other
> words, do NOT use conventional cardioid + cardioid phasing, or you gain very
> little (except extra F/B).