1. Set the VOX switch to ON

2. No need to press TALK; when the audio signal output from the communication system reaches the threshold, the walkie-talkie converter box automatically activates the TALK function, and the key backlight turns orange. The walkie-talkie can hear the sound from the wireless communication system; when the audio signal output from the communication system weakens, the TALK function automatically turns off, and the key backlight goes out. The walkie-talkie cannot hear the sound from the wireless communication, but the wireless communication can hear the sound from the walkie-talkie.