sign, signalize, betoken, indicate, bespeak, point, impressive, waveform, subaudible, singal, more...

silence, noise, conceal, hide, obscure

radio, television, cell phone, satellite, microwave, wireless, more...

electrical, received, digital, original, audio, clear, high, incoming, transmitted, strong, low

give the high sign,   to indicate,   to gesture,   to wave,   clear message,   to flag,   visual cue,   raise your hand,   my cue,   gps output