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[TenTec] " A Low vswr will kill you !"

To: <tentec@contesting.com>
Subject: [TenTec] " A Low vswr will kill you !"
From: SEWATKINS@dgs.state.va.us (Sherrill WATKINS)
Date: Tue, 23 Jan 2001 09:57:15 -0500
Also, I forgot to mention, and as Dr. Johnson stated in his post;  Mr. Maxwell 
was also referring to the fact that many hams incorrectly assume that if a 
given antenna system shows a low vswr then the antenna is operating correctly.  
Of course, this is unscientific and completely FALSE!  A low vswr is an 
excellent indication that loss may be occurring somewhere in the antenna 
system.  A good check for this is to operate the antenna in a nonresonant 
condition and see if the vswr increases as it should.  If it does not, then 
that is the clue that loss is occurring somewhere.  Many hams incorrectly 
assume just the opposite and say that their swr is low so they should be 
"getting out" !  Also, it has been explained in QST by several writers such as 
Mr. Doug Demaw, now a sk, that wideband antenna systems fed with open wire line 
should NOT be fed through a common balun.  Instead, they should be fed through 
a link coupled balanced output antenna tuner; i.e. E.F. Johnson "Matchbox" or 
equivalent.  Baluns will easily "saturate" at high vswr levels and convert the 
precious rf energy into heat.  Again, this produces a low vswr reading when 
loss in the system is occurring.  -  Corn - k4own.


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