lock on


Also found in: Dictionary, Idioms, Wikipedia.

lock on

i. One of the operating modes of most air-interception radar. When the pencil beam, after having searched and found the target, remains pointing at the target and continues tracking it automatically, it is said to “lock on.”
ii. In phase-lock radio receivers, to adjust the frequency of the voltage-controlled oscillation to the point where it is controlled by the signal power from the detector.