What do you mean? If you want to see the phase shift of an amp from
input to output, you need to compare input to output and look at the
zero crossing.
Hmm... how about a dual zero crossing detector, one from the output of
the sig gen, other from the output of the amp. The two zero crossing
signals into a phase shift to voltage converter. Sweep the frequency
(not too fast) with the sweep voltage on the X (horiz) input of the
Oscope. Output of the PS2V into the Y (vert) input of the scope. tada!
A rough graph of phase shift vs frequency.
So why am I not a millionaire? Oh, that's right, it's the salesmen and
management who make the big bucks.
Alien Steve
thought about that... but was looking for a really simple thing using existing components.
building a PS2V circuit takes me at least as long as measuring the phase shift point by point.
of course if you measure 100 units things are different.
If the scope is able to do add/subtract, what would one get?
i mean the signals are obviously in sync and same frequency.
You would of course need to normalize the amplitude on each channel, i think easy enough to do in any
lab with a series resistor and 2 diodes (or a shorted rectifier).
now switch to add on your scope and get 0 to 2*dide clamp voltage for 180 to 0 degree phase shift.
No opamp, no complicated circuit, no thinking required.
Most scopes can add/subtract (even my tek 7633 which i think is older than myself.)
Now, why am i no millionaire? guess you are right, simple solutions are no good for making
money nowadays... You need bad ideas, and loads of people annoying other people to make money.
ST
