... Communication distance: more than 500 meters in open landInstructionID setting, Coding, Transmit code, Receive code setting instruction: Press CALL. Number3, ... RED, GREEN light bright and enter into coding status. Coding time is 16 seconds. If coding successful will sounds 3 “Di..” while ... to enter into receiving code status. For example:When coding for two intercoms, should press number button 3 on ...