Re: Is it possible to simulate ac signal with dc?..tia sal

Don Bowey wrote:
On 9/19/05 7:28 AM, in article FWzXe.10$tz3.1345@xxxxxxxxxxxxxxx, "Don
Stauffer" <stauffer@xxxxxxxxxxxx> wrote:

One problem with some of these discussions is that there are two
definitions of DC. One has DC as any signal always of the same polarity,
another requires DC to have the same value throughout time.

DC with a varying voltage but always the same polarity can of course be
changed to AC by running the signal through a capacitor.

Another problem I have seen whose argument reduces to the above is a
pulse width modulated signal but always of the same polarity (if you can
call zero volts a polarity- however, to overcome this problem one can
consider a PWM signal from a small fraction of a volt to many volts).

Another argument I have seen rage from the PWM situation is whether a
PWM signal is analog or digital :-)

Answering the practical question of a newbie with this type of
hypothetical/metaphysical nonsense is...... Well, garbage.

I wonder if these considerations of DC began with the musings of some
complete idiot, or some idiot with a phd attempting to think outside the box
(an incomplete idiot).

No, I think that this thread is finally onto what the original poster wanted to know. i.e. does the voltage of the centre pin of the phono connector stay above the ground connection or does the voltage alternate between say -1v and +1v. Both of these would generate an audio signal but only one would be true AC, the other would be pulsed DC.

Having said that, I still don't have an answer to the original poster's question.
.

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