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Re: Phase vs. Polarity (was Playing Edison Diamond discs)

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Wed, 6 May 2015 17:36:16 -0700

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 ```Tom, I believe you're correct, but I fear we're playing a little loose by talking about degrees. One can only phase shift relative to a specific frequency. A phase shift of 180 degrees in a pure sine wave of frequency f would shift that sine wave one-half wavelength, where the wavelength is computed from f. It doesn't make sense to talk about a phase shift to an arbitrary signal -- exactly how much would you be shifting it? That said, now that I know that the terms are used somewhat loosely (for historical reasons, I guess) I'm satisfied that I understand the discussion. Thanks to everyone who weighed in! On 5/6/2015 5:23 PM, Tom Fine wrote: > So is it correct to say that there can only be a polarity reversal > (180-degrees) whereas there can be any degree of phase shift? > > -- Tom Fine > > ----- Original Message ----- From: "Ellis Burman" > <[log in to unmask]> > To: <[log in to unmask]> > Sent: Wednesday, May 06, 2015 7:32 PM > Subject: [ARSCLIST] Phase vs. Polarity (was Playing Edison Diamond discs) > > >> On Wed, May 6, 2015 at 12:35 PM, Ron Roscoe <[log in to unmask]> wrote: >> >>> Oi! Phase, polarity........... >>> Polarity is just a special instance of phase shift; 180 degrees! >>> >>> >> This is incorrect. >> >> Consider an asymmetrical waveform, say square on the positive half, but >> triangular on the negative. Phase shifting it one half cycle (180 >> degrees) >> and adding it to the original waveform will NOT cancel it out. >> >> Only inverting the polarity will cause it to cancel. >> >> >> Ellis >> [log in to unmask] >> 818-846-5525 >> >> > -- *Pete Tinker* West Hills, CA 91307 818-three/four/six-5213 818-six/nine/four-5213 /(cell)/ ```