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[AMPS] Where to read Reflected Power

To: <amps@contesting.com>
Subject: [AMPS] Where to read Reflected Power
From: measures@vcnet.com (measures)
Date: Mon, 27 Sep 1999 14:03:00 -0700
>
>Jim,
>
>Lots of possible issues on this one.
>.......
>.......>Lastly, many hams think that if they tune their tuner, that their 
antenna 
>is now a 50 Ohm antenna.  WRONG!  The only thing a tuner does is to 
>essentially act as a buffer between your exciter and your load.  It will 
>not improve a bad antenna.  If the antenna has a 15:1 VSWR without the 
>tuner, it still has it with the tuner.  You just don't see it.
>
?  Thick sliced bologna.  .  .  If a 15 to one / 750 ohm antenna is 
connected to a matching network/antenna tuner, the 750-ohms is 
transformed to 50-ohms +/- j0 ohms. 

 >........I wouldn't worry about your variances in SWR readings.  It's 
>really just to give you an idea of what kind of power is coming back at 
>your rig.  Personally, I'd match it so that the PA sees the best possible 
>match.  This means that your tuner and whatever you have on the output of 
>your PA are optimally matched.  Who cares what the SWR meter in the tuner 
>sees.  The output of the tuner is going to have a high VSWR anyhow!  
>Matching this way will cause you to put the maximum available power into 
>the tuner instead of reflecting 2.5% of it back to the amp.
>
?  However, without a tuner, the 2.5% gets reflected back to the antenna. 
 
>
-  later, Jon.

-  Rich..., 805.386.3734, www.vcnet.com/measures.  


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