Hi Kevin,
No, I'm not confusing it. I know what 180 degrees out of phase means, vs.
any other phase angle. And I know what a vector sum means. My only mistake
was in using the vernacular instead of spelling out in great depth exactly
what I meant. Sorry for the confusion. As I said, in the cases I am
familiar with, we use 180 degrees out of phase. Anyway, this has gotten to
be a dead horse, so I am going to give everyone a break and drop the
subject.
Regards,
Gary
----- Original Message -----
From: "Kevin Purcell" <kevinpurcell@pobox.com>
To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
Cc: "Kevin Purcell" <kevinpurcell@pobox.com>
Sent: Friday, June 01, 2007 12:31 PM
Subject: Re: [TenTec] CW Tuning with Omni 6 Plus
> You are confusing two usages of "out of phase":
>
> 1. having 180 degrees (pi radians) phase difference
>
> 2. not being in phase -- having a phase relationship of anything
> other than zero phase difference
>
> As Jerry said adding two signals that are precisely 180 degrees phase
> difference will result in a zero amplitude signal. Adding two signals
> with a random phase relationship will result in a higher amplitude
> signal.
>
> The latter case is "always" the case unless you have the two tones
> both phase-locked. Which you won't have in tuning two separate
> oscillators. Their phases will be just randomly related.
>
> When you zero beat something you are going for zero frequency
> difference between the tones -- the audible beat signal goes to zero
> FREQUENCY not zero amplitude sum tone.
>
> On May 31, 2007, at 7:33 PM, Gary Hoffman wrote:
>
> > That's what I said Jerry....or at least tried to say. Normally, in
> > applications I have experience with the signals are out of phase
> > and thus
> > cancel. This, in my personal view, is the most useful
> > configuration. But,
> > as I said, if someone does something else with the phase (i.e., in
> > phase
> > instead of out for instance) then they could add.
>
> --
> Kevin Purcell
> kevinpurcell@pobox.com
>
>
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>
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