[CQ-Contest] Coax Stubs for SO2R

[K3RAG LB3RE Brobakken]

Hello
Have anyone tried RG11 75ohm or  cheap RG6 CATV cable for stubs???
Need something for our scout club JOTA LA6JAM 
73 LB3RE Rag
onsdag, 27 juli 2016, 00:17a.m. +02:00 from Steve NR4M  steve at nr4m.com :

>Jim,
>
>Been following this thread since it started (this time) several days 
>ago.  I have lots of interest in it as I have a multi multi station here 
>in VA.
>I have built coaxial stubs in the past using my AIM 4170, FSJ4 heliax, 
>and K2TR's data as a good place to start.  I think after screwing with 
>them for years, I've gotten pretty good at putting the nulls where I 
>want them.  And, they seem to work, but no real data on how well they 
>work.  My 40m 3rd harmonic on 15 is about S-5 and I can get withing a 
>couple of KC, or so.  It's just not much of a problem any longer.
>
>Been quite interested in your suggestions on how to place them for 
>maximum attenuation of the undesired RF.  I, like many, I guess, have 
>installed them at the output of the amplifier, because that would be a 
>50 ohm point in a properly tuned amp.  But, now I see that it's more 
>important to know what the impedance of the harmonics is on your band of 
>choice.
>
>What got me up and moving on this is your comment in a previous post 
>today about it being the second harmonic that's important.  I have been 
>building stubs, per N2TR, that covered multiple bands, without really 
>focusing on a particular stations 2nd harmonic.
>
>I pulled the coax off the stub set on the back of my 20 meter amp, 
>connected a Rig Exper AA54, and started looking up my coax toward the 
>antenna.
>On 10 meters, I saw R101 -J14.6 and on 15 (for the heck of it) I saw 
>R112 j-36.
>
>Following your instructions in your pdf on locating the stubs, I am just 
>about where I need to be.  If I added .44 feet of Coax, it would be 
>right on the voltage peak.
>
>Do these numbers above look as they should?  I was expecting higher R.
>-- 
>
>73 de Steve, NR4M
>
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