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The true impedance of a quarter wave antenna, normally falls between 35-40 ohms.
What your looking for on the analyzer is this
Z=R or very close
X=0
This is where the antenna is truly resonant = greatest efficiency.
This normally occurs at about 1.4:1...1.5:1
When you tune the antenna for the "magic 1:1...you will normally see that X has a value Greater than 0...This is called reactance. Reactance (X) causes wasted power.
The trick on the analyzer is where is this point reached.
You need to measure the antenna on several channels.
Channel 1...better/worse
Channel 20...better/worse
Channel 40... better/worse
Looking at not only VSWR but X
If VSWR and X is lower on Ch:1 then then the antenna should be to long
If this occurs on Ch:40 then the antenna is too short
If you run the test in sweep mode as 4string suggested, the analyzer will tell you the point of resonance.
Hope this helps
All the Best
Gary

<blockquote data-quote="BJ radionut" data-source="post: 742119" data-attributes="member: 7026">The true impedance of a quarter wave antenna, normally falls between 35-40 ohms.What your looking for on the analyzer is thisZ=R or very closeX=0This is where the antenna is truly resonant = greatest efficiency.This normally occurs at about 1.4:1...1.5:1When you tune the antenna for the &quot;magic 1:1...you will normally see that X has a value Greater than 0...This is called reactance. Reactance (X) causes wasted power.The trick on the analyzer is where is this point reached.You need to measure the antenna on several channels.Channel 1...better/worseChannel 20...better/worseChannel 40... better/worseLooking at not only VSWR but XIf VSWR and X is lower on Ch:1 then then the antenna should be to longIf this occurs on Ch:40 then the antenna is too shortIf you run the test in sweep mode as 4string suggested, the analyzer will tell you the point of resonance.Hope this helpsAll the BestGary</blockquote>

[QUOTE="BJ radionut, post: 742119, member: 7026"] The true impedance of a quarter wave antenna, normally falls between 35-40 ohms. What your looking for on the analyzer is this Z=R or very close [B]X=0[/B] This is where the antenna is truly resonant = greatest efficiency. This normally occurs at about 1.4:1...1.5:1 When you tune the antenna for the "magic 1:1...you will normally see that X has a value Greater than 0...This is called reactance. Reactance (X) causes wasted power. The trick on the analyzer is where is this point reached. You need to measure the antenna on several channels. Channel 1...better/worse Channel 20...better/worse Channel 40... better/worse Looking at not only VSWR but X If VSWR and X is lower on Ch:1 then then the antenna should be to long If this occurs on Ch:40 then the antenna is too short If you run the test in sweep mode as 4string suggested, the analyzer will tell you the point of resonance. Hope this helps All the Best Gary [/QUOTE]

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