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Does the output of a electronic sine wave oscillator end with a positive half cycle or a negative half cycle?
My question was not clear and probably will not be after this.
Assume the oscillator is operating with just enough positive feed back to sustain oscillations. This means the feed back only affects the oscillator operation during a few degrees (maybe only one degree) of a cycle of operation. Now the sine wave oscillator ceases to oscillate because of an abrupt and complete lack of positive feed back.
2 個解答
- TechnobuffLv 76 年前
The start point is what you decide to make it. The end point is that same point on the next cycle.
Usually, we consider a sine wave to begin at 0 degrees (0 voltage etc.), pass through 0 again after 180 degrees, then finally end at 360 degrees (which is also 0).
A sine wave is related to a simple rotary action. You can determine its value at any point in its rotation by finding the sine of the angle of rotation.
If the first 90 degree of rotation is a positive excursion, all angles beyond 180 degrees will be negative excursions.
Sine 90 = 1, sine 180 = 0, sine 270 = -1, sine 360 = 0.
You can see that 90 and 270 degrees are the peaks of opposing but equal polarities.
- 異域秦後人Lv 76 年前
BOTH ! ONE HALF SINE WAVE TAKES 180 DEGREE IN POSITVE, AND OTHER HALF SINE WAVE TAKES THE REMAIN 180 DEGREE IN NEGATIVE.
