Noise power is a one-sided distribution, so the average is positive. We don’t have negative noise power.
Ideally, it will average to a flat (white) distribution, but what we hear in the aether is not ideal. So we get a display that shows signals and less-random noise/interference. wunder K6WRU Walter Underwood CM87wj http://observer.wunderwood.org/ (my blog) > On Dec 9, 2015, at 5:23 PM, Jim Brown <[email protected]> wrote: > > On Wed,12/9/2015 5:05 PM, Greg Troxel wrote: >> Can you explain "averages to zero"? I would think that random noise >> would average to something non-zero and then be comparitively reduced by >> the averaging interval, and thus more like the normal noise level over >> sqrt(N). Perhaps this is then reliably below the threshold for any >> color to appear, which would make it effectively zero. > > Perhaps I chose my words poorly. What happens when you set averaging and > levels to optimum is that any random noise averages itself out (BECAUSE it's > statistically random), so you're left with whatever weak signals and > non-random noise is on the band. > > 73, Jim K9YC > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[email protected] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to [email protected] ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [email protected]
