61.VOR 導航原理是比較:
(A)參考和變化信號相位‧The reference phase signal and variable phase
signal. (B)參考和固定信號相位‧The reference phase signal and fixed
phase signal. (C)參考和控制信號相位‧The reference phase signal and
control phase signal. (D)參考和資料信號相位‧The reference phase signal
and data phase signal.