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In the phase cycle, the receiver "follows" the starting phase of the sample net magnetization, leading to addition of four positive absorptive peaks. In pulse sequence programing, the +x/ axis is given a code of 0, +/ is 1, —x! is 2, and — y' is 3, so we would say the pulse phase is 0 12 3 and the receiver phase is 3 0 1 2. The important point is that every time we advance the phase of the pulse by 90°, which advances the starting position of the net magnetization by 90°, we also advance the receiver phase (our point of view) by 90°, so it looks the same in each scan. But we are alternately exercising different physical receiver channels (Mx and My ) so that any imbalances in the two channels will cancel out and there will be no quadrature artifacts in the spectrum.

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