Electrically isolated push-to-talk devices

Abstract

Communications systems containing an electrically-isolated Push-To-Talk (EI-PTT) device are described in this application. The communication systems contain multiple radios, a microphone/headset, and a centralized power supply. The systems also contain an EI-PTT device which reduces or eliminates noise that can disrupt the audio transmission. The EI-PTT device allows an operator or user of the communication system to actuate a button which remotely switches the radio from receive mode to transmit mode. This allows multiple users to listen (receive) to communication traffic on the same frequency at all times, but only speak (transmit) on the frequency while activating the EI-PTT device. Unlike other PTT devices which electrically tie the ground signals inside the device, the EI-PTT devices electrically isolate the ground signals to reduce the problem of noise coupling. Other embodiments are described.