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
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
>> and adding it to the original waveform will NOT cancel it out.
>> Only inverting the polarity will cause it to cancel.
>> [log in to unmask]
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