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[TowerTalk] Re: [AMPS] True Or Not True #2

To: <amps@contesting.com>
Subject: [TowerTalk] Re: [AMPS] True Or Not True #2
From: 2@vc.net (2)
Date: Fri, 7 Sep 2001 03:25:55 -0700
>
>> However, if the signal was at or near the noise level, then 2 db
>> increase could make the signal more easily read.  A 2db increase is
>> like Christmas to someone using a single yagi for moonbounce.
>
>Even 1dB is a huge increase when copying a signal near noise. 
>The error rate changes considerably here when working CW, when 
>I pick antennas that offer even 1dB more S/N ratio.
>
>Most S meters are in the area of a dB or two at the low end of the 
>S scale, expanding as they get up around S-9 and they work fairly 
>well from that point on. My ICOM's are that was, as is my Yaesu 
>stuff. Almost no receivers are 6dB, most are 3 to 5 at the middle 
>scale. Most receivers actually tried for 5 dB per S unit, not 6. But 
>of course the calibration is often all over the place in different scale 
>areas, being much fewer dB per S unit at the low end. 
>
>Because we often see a 1 S unit change when it is only 2dB or so, 
>we often don't realize how much a dB or two actually means on 
>weak signals.
>
>That's also why so many antennas have "supergain" or super F/B 
>on the air. Because people just assume an S unit is 6dB.
>
//  At one time, an S-unit increase was defined as a doubling of received 
voltage -- i.e., a 6db increase.  

-  R. L. Measures, 805.386.3734,AG6K, www.vcnet.com/measures.  
end


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