LvW
Advanced Member level 6

For an oscillator, I expect that the loop phase at the gain crossing point (0 dB) also is zero (360 deg).
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Yes - FvM is right. my comment applies to the IDEAL oscillation condition only.
Hence, it is better and more realistic to say: At the frequency where the loop phase crosses the 0 deg line (360 deg) the loop gain (magnitude) must be larger than unity.