Preferably, the phase difference should be about 40 degrees to create a near in-phase effect.

优选地，相位差应约是40度，以产生近似的同相效应。

youdao

Preferably, the phase difference should be about 40 degrees to create a near in-phase effect.

优选地，相位差应约是40度，以产生近似的同相效应。

youdao