Topband: Impressive demonstration of one dB of signal strength improvement

[donovanf at starpower.net]

These recordings are an impressive demonstration of the benefit of 
one dB of signal strength improvement in a weak signal situation. 


Click on the links on this website: 



www.ab7e.com/weak_signal/mdd.html 


73 
Frank 
W3LPL 


----- Original Message -----

From: "David Gilbert" <xdavid at cis-broadband.com> 
To: elecraft at mailman.qth.net 
Sent: Wednesday, August 21, 2019 7:02:21 AM 
Subject: Re: [Elecraft] KPA500 Coax size requirements 


That's not a universally true statement. 

Several years ago I was trying to decide which antenna to buy, and my 
choice came down to two antennas that were 2 db apart. I created some 
audio files by recording typical band noise and then overlaying them 
with recorded CW messages at various strengths. The difference between 
1 dB above the noise level and 2 dB above the noise level can make the 
difference between no copy and copy. The files and testing methodology 
can be found here: 

http://www.ab7e.com/weak_signal/mdd.html 

If you're ragchewing it doesn't matter, but if you're trying to make a 
contact and your signal is at the level of the mud it does. 

73, 
Dave AB7E 

On 8/20/2019 9:18 PM, Jim Danehy wrote: 
> ONE DB loss is the LEAST DETECTABLE amount a human can detect. Hardly if not impossible to notice. 
> 
> Jim 
> W9VNE/VA3VNE