Like so many other physical phenomena, the effect of zero beating is so
difficult to express in words, but with several simple vector diagrams the
whole situation becomes obvious.
----- Original Message -----
From: "Duane Calvin" <ac5aa1@gmail.com>
To: "'Discussion of Ten-Tec Equipment'" <tentec@contesting.com>
Sent: Friday, June 01, 2007 9:16 PM
Subject: Re: [TenTec] CW Tuning with Omni 6 Plus
> Exactly - zero beat is when the "beat note" between the two tones goes to
> zero Hertz. Hence, zero beat. Musicians know all about this when they
> tune
> their instruments.
>
> 73, Duane
>
> Duane Calvin, AC5AA
> Austin, Texas
> www.ac5aa.com
>
> -----Original Message-----
> From: tentec-bounces@contesting.com [mailto:tentec-bounces@contesting.com]
> On Behalf Of Ken Brown
> Sent: Friday, June 01, 2007 6:20 PM
> To: Discussion of Ten-Tec Equipment
> Subject: Re: [TenTec] CW Tuning with Omni 6 Plus
>
> When two tones (RF or audio) are at exactly the same frequency, they are
> "zero beat" with each other. They could be at any phase relation to each
> other, so the amplitude of the sum of the two could be anywhere from
> twice that of one of them or zero. Without careful amplitude adjustment,
> the two tones will not be equal, so twice the amplitude, or zero, will
> seldom occur. Even with careful amplitude adjustment the phase relation
> will seldom be exactly zero or 180 degrees, so double amplitude or zero
> amplitude sums will still be rare.
>
> Having said all of that, the sum is just as likely to be lower amplitude
> as it is to be higher than that of either single tone.
>
> James Duffer wrote:
>> snip
>>
>>> When the "cw" button is pushed you get a sidetone. While holding
>>> down
>
>>> this button you move your dial until your target's tone is "beating"
>>> against your sidetone. When you move the dial enough so that your
> sidetone
>>> no longer "beats" and the tones are "insync" they become "one". When two
>>> tones become "one" the tone gets louder. This is "zero beat". Even
>>> having
>
>>> just "beating" is close enough for govt work.
>>>
>> snip
>>
>> For many years I have been under the impression that "zero beating" was
> the
>> method of beating (hetrodyning) of two frequencies bringing their
> difference
>> down to the audible range and adjusting one to match the frequency of the
>> other so that the two tones beat against each other producing "zero" out.
>
>> Thus the term zero beat. Not a louder tone.
>>
>> de wd4air
>>
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>
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