[Elecraft] On zero beating

[cyr999@extremezone.com]

Now there's a really cool idea!!! I second the motion. 73/Tim

Quoting Steve Lawrence <Steve.Lawrence@ITWFEG.COM>:

> Tim,
> I too have found this difficult to hear with a discontinuous CW signal.
> 
> The "beat" is produced by the difference in the two audio frequencies:
> the 
> spot tone and the apparent tone of the CW signal.  The beat frequency
> goes 
> down as the differences are minimized further, until the beat is zero --
> 
> indicating perfect match in frequency.  The ear hears a subtle 
> Wah...wah...wah...wah which is the beat note indicating the frequencies
> 
> are not quite matched.  A slight change in the tuning dial, increases or
> 
> decreases  the period of the beat note or the separation of the 
> wah.......wah......wah......  The desire is to decrease the beat
> resulting 
> in matched frequencies.
> 
> This is easy for me to hear when tuning my guitar, and I suspect a
> violin 
> to be much the same.  Here the tones are long and continuous.  But the
> 
> key, as you well point out, is two continuous tones -- not the case in
> 
> spotting a CW signal.  So, like you, I struggle on the non-continuous 
> signal.
> 
> Perhaps the "ultimate" spotting tool would be to measure the audio 
> frequency of a received CW signal and display it -- perhaps at the touch
> 
> of a button.  Knowing your sidetone is set to, say 700Hz, you could then
> 
> adjust the dial frequency so the received CW signal is also at 700 Hz.
> 
> Since the K2 has a frequency counter logic, perhaps this feature could
> be 
> implemented?
> 
> Steve
> aa8af
> 
> 
> 
> 
> 
> 
> 
> 
> cyr999@extremezone.com
> Sent by: elecraft-admin@mailman.qth.net
> 01/17/2002 03:04 PM
> 
>  
>         To:     Elecraft Reflector <elecraft@mailman.qth.net>
>         cc: 
>         Subject:        [Elecraft] On zero beating
> 
> 
> Hi folks - 
> 
> Although it may be clear as a bell to most people, I thought I would
> share 
> my 
> experinces as a beginner with zero beating. It may be of interest to 
> newcomers 
> in HAM.
> 
> Every text I've read seems to define zero beat by referring to the word
> 
> "beat". 
> I never HEARD any "beat". What the heck was everyone talking about! I 
> never new 
> what that "beat" was and finally got too embarassed to ask people
> anymore 
> about 
> it.
> 
> In the mean time I would tune in on a signal by simply using SPOT and 
> matching 
> the tone by ear. Since I play the violin, this is very easy for me. On
> the 
> other 
> hand, my Code Buddy from FISTS finds that type of thing almost
> impossible.
> The other way I tune is simply to get the signal as loud as I can in the
> 
> narrowest filter setting. With my K1 and K2 that seems to always be just
> 
> about 
> dead on.
> 
> For you fellow beginners, I was FINALLY enlightened when installing the
> AF 
> 
> filter the other nite. The manual said to zero beat the CONTINUOUS tone
> at 
> 
> 7000.00. MAGICALLY WHEN THERE IS A CONTINUOUS TONE ZERO THE DEFINITION
> OF 
> BEAT 
> BECOMES TOTALLY OBVIOUS. As soon as you are dead on the two tones sound
> as 
> if 
> they are one tone which has a rhythmic rise and fall of the tone. This
> 
> rise of 
> the tone is the beat. When you listen to code being sent, you do not
> have 
> a 
> CONTINUOUS wave - so you seldom have the signal coming in long enough to
> 
> hear 
> this illusive beat!!!! Key word here: continuous :-)
> 
> I guess what I am trying to share is what the word BEAT really refers to
> 
> if you 
> were confused like me. Also, once I heard what the beat was on the 
> contiuous 
> wave, it helped me with matching the SPOT even more - you may not hear
> the 
> beat 
> per se when receiving code, but you can hear when it's getting right in
> 
> the 
> groove. Perhaps listening to really fast ops sends such a rapid signal
> 
> that you 
> hear even more of a beat.
> 
> Anyway, I found this simple thing to be a true revelation. If it's 
> confused you 
> - go down to 7000 without the antenna etc etc and you will be able to 
> learn the 
> true basis of the word BEAT. 
> 
> Sorry to bore you experienced folks with this simplicity!! If I've said
> 
> anything 
> that needs correction or the voice of experience - please jump in so I
> 
> don't 
> mislead anyone!
> 
> 73/KB7OEX Tim Logan 
> 
> 
>