Topband: Small loop Performance

[W2PM]

I think a key success factor is for us to get past the magic and wives tales and look at the fundementals. What is the local situation wrt local crud noise, how localized or generalized is it, what are the baseline characteristics of each antenna being considered wrt vertical angle, azimuthal directivity, output, the distance from shack to antenna wrt proper feedline treatment to avoid common mode pickup and the location of the proposed antennas to everything else which can affect them. 

This is why I find on4un books so useful even tho many of the designs are far out of range for me. They show the idealized performance targets so you can more intelligently evaluate all the practical options. 

73

Sent from my iPad

On Apr 13, 2012, at 6:36, "Dennis" <dennisissure at comporium.net> wrote:

> GM to the group...........for what it is worth, I have had the fortune and 
> opportunity to work DX on 160
> from the Midwest to the West Coast of the State of Washington and back to 
> the mid west and now in
> SC on the East Coast.  It took me 27 years to work 125 countries on top band 
> using ONLY the TX ant
> as also my RX ant.  Yes, I did have a 10' diameter loop made of hardline 
> when I lived in the Seattle,
> Wa area in Auburn, Wa.  It worked great and worked even better after Mike 
> VK6HD sent me an amp
> for it.  Things started to look up and the DX started to roll in across the 
> loop.
> 
> Moving from the west coast back to the midwest didn't really change things 
> that much other than the
> mean run of JAs was not as good as it was in WA but still plenty of 
> opportunity.  Speaking of Opportunity,
> I think it is important to mention that many DX station operate through what 
> I like to call the Window
> of Opportunity which is simply a time frame when they come out of the noise 
> peak to a maximum level
> and quickly drop out.  This windows sometimes can be as long as 4 to 5 
> minutes and as short as just
> a few seconds depending on propagation.
> 
> I have since explored the realms of many of the various types of RX antennas 
> from the BOG to the Pennant,
> EWE, FLAG, 2-turn shielded loops and short beverages.  A limited space city 
> lot is not exactly the place
> to experiment with these antennas, but I have a case where there is a wooded 
> area on the back side of the
> property line and extends for nearly 3/4 of a black for 180 degrees and 
> allows me to put up and try
> these antennas.  After much experimenting, I finally settled with the K9AY 
> antenna and getting the boards
> from Far Circuits and the other hardware and enclosures from Ten Tec and 
> Home Depot I built my own K9
> assembly for under $125.00 and it is the best answer to a city dwellers DX 
> chasing adventures.  It allows
> one to hear the DX stations when they come on which is the answer to working 
> any DX ,  YOU CAN'T WORK
> WHAT YOU CAN'T HEAR & YOU CAN'T ALWAYS WORK WHAT YOU DO; HOWEVER, IT SURE 
> CHANGES THE
> ODDS ON THINGS WHEN THE GOIN GETS ROUGH.  Without the K9AY antenna system I 
> wouldn't have heard or
> worked many of the new DX-peditions that showed up this past year on Top 
> band.
> 
> Just remember this, there are three things that make up an effective and 
> efficient top band station.  By far, they
> are not Power in the form of KWs, nor Expensive Equipment or 
> Cheating.................it is the Following:
> 1--the antenna
> 2--The Antenna
> 3--THE ANTENNA---------------the antenna can't be over exaggerated when it 
> comes to performance and efficiency.
> Like anything else in life, you get out what you put into the efforts and 
> then you reap the rewards of the same at the end.
> An efficient transmitting antenna along with an efficient receiving antenna 
> will put you into the reward section
> a lot sooner than calling for hours to a DX station you simply can't hear. 
> The cluster reports that he is active; but
> it doesn't mean you are going to work them if you don't have the knowledge 
> or equipment to do so.
> 
> I see as much as 34 and 30 db of nulling on signals from the back side with 
> my K9.  I check it against AA1K, W4ZV, N4IN and
> several others statioins to include W8JI and mid west stations just to make 
> sure it is still performing.  Being laid up with
> and fighting Cancer now for 6 years as well as being retired affords me the 
> extra time to do the things I enjoy and still able to
> talk about them.   I hope this little excerpt hasn't offended anyone and I 
> certainly hope that it has shed a different light on the
> less knowledgeable and will create an incentive for them to strive for 
> better systems at their locations.  73s all, and see you in the
> pileup or whatever.
> 
> de 
> K4CKDennis........................................................................................
> 
> -----Original Message----- 
> From: Gary and Kathleen Pearse
> Sent: Thursday, April 12, 2012 9:42 PM
> To: topband List
> Subject: Re: Topband: Small loop Performance
> 
> Well, my Wellbrook might work as well yours, as I too have worked CE/K7CA 
> with mine on 160 from the Black Hole of KL7. More than once as well.
> 
> For me the magic isn't directional gain, it's the improved S/N and the 
> ability to null local single point QRN.
> 
> If I were able to extend a Beverage or three I'd do so. Unfortunately the 
> city snow plows would allow none of that.
> 
> Gary NL7Y
> 
>> 
>> However, in terms of pulling
>> in DX, again, one loop is generally as good as another.
>> Using the loop design I wrote up in the National Contest
>> Journal, I've heard DX such as CE/K7CA on my loop, but other people
>> have built the same loop design and not gotten such good
>> results.  Assuming they properly duplicated the design,
>> it is just one of those Your Results May Vary situations.
>> It would be very unlikely that the Wellbrook or some other
>> loop would produce significantly different results.
>> 
>> Rick N6RK
>> _______________________________________________
>> UR RST IS ... ... ..9 QSB QSB - hw? BK
> 
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK 
> 
> 
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK