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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)/