Ok, I think I figured out where I was glossing stuff over. Many of you made the observations but I could sense that for me there was something missing in the way I understood the various circumstances. I woke up this morning and it all seemed to click.
Phase: Phase is a condition that compares two signals where one signal is referenced to another.
Phase Shift: Phase Shift can be described in terms of angle or time.
Phase Shift Angle: Phase Shift Angle only applies to periodic wave forms of a single frequency, and more specifically to a sine wave of a single frequency. Phase angle is specifically a measure of time describing the duration between two points on a sine wave of some specific frequency.
Phase Shift Time: Phase Shift as time, e.g. milliseconds, can apply to wave forms that represent multiple frequencies combined. Phase Shift described as time can be useful to describe changes in phase when the use of the concept of phase angle does not apply.
Phase difference: is the difference, expressed in electrical
degrees or
time, between two waves having the same frequency and referenced to the same point in time
[1] Comparing Polarity and Phase Angle:
If a sine wave at some specific frequency is compared to an example of
the very same sine wave that has been flipped across the baseline it is thought to have reverse polarity. It is incorrect to describe this condition of reverse polarity as 180* out of phase because angle of phase, as it applies to a sine wave of a specific frequency, describes a passage of time referenced to the time it takes to complete 1 cycle at the frequency of the sine wave. If the polarity is simply reversed and there is no shift in time then the use of the parameter "phase angle" does not apply. The term Phase Angle does not merely describe a geometric angle. Phase angle is specifically a measure of time describing the duration between two points on a sine wave of some specific frequency.
If a sine wave at some specific frequency is compared to
another sine wave of the very same frequency and the
phase difference of the two sine waves is in fact 180* then it may be said that the sine waves effectively have reversed polarity.
If a waveform, made up of a combination of multiple frequencies, is compared to a second example of
the very same waveform that has been flipped across the baseline it is thought to have reverse polarity. It is incorrect to describe this condition of reverse polarity as 180* out of phase because angle of phase does not apply to a waveform made up of a combination of multiple frequencies. The the use of the parameter "phase angle" is frequency specific. Consideration of phase angle can not apply to waveforms that represent combinations of multiple frequencies.
Phase Cancellation: Phase Cancellation is a term that refers to the effects of Constructive Interference and Destructive Interference as it applies to the phenomena of wave propagation.
I have thought, for many years, that I understood this, but this morning was the first time I was able to see it all at once and make sense of the parts I had left muddled as a convenience.
Thank you to everyone for making comments and taking the time to help me focus my thoughts.
As always, if I have made some statement that warrants correction I am eager to learn about it and continue learning.
Thank You.
post edited by mike_mccue - 2014/07/30 09:59:30