[Elecraft] Re: CW Listening Tones

[Thomas M. Beaudry]

There was an article in QST a good many years ago about close spaced tones
being easier to seperate at lower frequencies.  They cited a physiology
reference that our ability to distinguish seperate tones is based on the
percentage of seperation and not the absolute seperation...

>
> Independent of the "aging operator" theory, there's an intuitive
interpretation
> of why a serious CW op might prefer a lower pitch on receive. Consider two
> signal separated by only 10 Hz. If one is 1000 Hz and the other 1010, the
> difference between the two is just 1 percent. But if one is 500 Hz and the
other
> 510, the difference is 2 percent. I haven't tried this under controlled
> conditions. But based on on-air experiments, it does appear that when two
> signals are close-spaced and interfering with each other, tuning them to a
lower
> pitch improves copy. (The K2 facilitates experimenting with this since you
can
> set up two filters with the same bandwidth but widely spaced BFO
frequencies.)
>