[Elecraft] Zero beat

[Ron D'Eau Claire]

You may be quite right, Tom. Many of us have various levels of hearing loss.

However, the "red flag" that causes people to say things like that is the
use of the phrase "matching tones". 
There is *no* "matching tones" in the process of zero beating, which gives
the impression the person is trying to do the wrong thing! 

We don't care what frequency the "tones" we're hearing are. We are listening
for the third tone that disappears when "zero beat" is achieved. So it's
only a matter of hearing whether a tone is there or not. 

It WAS easier in the "old days" because there was only one tone and we tuned
until it disappeared completely. Nowadays we have three tones, only one of
which disappears at 'zero beat'. 

Having the other two tones, whatever frequency they might be, at the *same*
level makes the third tone as loud as possible so it's easier to hear when
it disappears. 

Having followed this thread many times over the past decade, I'm becoming
convinced that some people have a very hard time hearing more than one tone
at a time. Even minor QRM on a CW signal stops them cold unless they can
filter it out in the receiver. For such people hearing the third tone is
probably very difficult or impossible. 

Many of us OTs have for years used very broad receivers on CW and learned
long ago to listen to several signals at once, picking out the one we want
to copy just as one picks out one conversation out of many in a crowded
room. Perhaps what we're seeing today is a side effect of modern receivers
where listening through real QRM is almost unknown.

73, 

Ron AC7AC 

-----Original Message-----
From: elecraft-bounces at mailman.qth.net
[mailto:elecraft-bounces at mailman.qth.net] On Behalf Of Tommy Alderman
Sent: Tuesday, February 01, 2011 1:58 PM
To: elecraft at mailman.qth.net
Subject: Re: [Elecraft] Zero beat

Nooooooooooo! If you served on an aircraft carrier for three years, with
Navy jets literally landing on a 13-inch thick steel deck just seven feet
above your bed, there are a LOT of things you cannot hear anymore and
matching audio tones is one of them!!

There are exception to every "One can easily....."!

73,
Tom - W4BQF