[Collins] Re: {Collins} Re: KWM-2 Low RF Output-PROBLEM SOLVED

[Robert & Linda McGraw K4TAX]

Just goes to prove that the SWR indicators that we often use and rely upon 
do not actually tell the true story.  More than once I've found the SWR 
bridge to indicate something other than a proper match.  Remember that these 
devices are "relative indicating" and thus are not absolute.  Example, if 
the source Z is 100 ohms and the load Z is 100 ohms the SWR indicator will 
indicate 1:1, and again if the source Z is 25 ohms and the load Z is 25 ohms 
then the SWR indicator will still indicate 1:1.

Also as indicated by Roy and Kurt, with a loose shield connection thus 
allowing current to flow outside of the line, the SWR indicator doesn't have 
a clue as to what is actually occuring.

73
Bob, K4TAX

----- Original Message ----- 
From: "Roy Morgan" <roy.morgan at nist.gov>
To: <DomD at comcast.net>; "Collins Mail List" <collins at mailman.qth.net>; 
"Collins Reflector" <collins at listserve.com>
Sent: Monday, October 04, 2004 8:37 AM
Subject: {Collins} Re: KWM-2 Low RF Output-PROBLEM SOLVED


> At 04:52 PM 10/3/2004, Dom DiClementi wrote:
>>... Kurt peaked my interest by suggesting that it was an SWR
>>problem.  Although my SWR bridge was indicating 1:5 to 1 or less on all
>>bands ... a loose shield connection at a coax switch which solved the 
>>problem.
>
> I would suspect the SWR indicator.
>
> Roy
>
> - Roy Morgan, K1LKY since 1959 - Keep 'em Glowing!
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