This application note was created to show how audio gating in ECS can be used to indicate which two-way radio is the source of audio when multiple radios are displayed on a user's panel.  By using Audio Gating and Audio Presence Tally we can determine which radio in a multiple radio system is the cause of the audio traffic we hear by displaying a tally on the users' panels.We select the FOR-22(s) being used for two-way radios and highlight the row to gain access to the advanced settings on the right hand side. At the bottom of the advanced settings for the FOR-22 is the Voice Operated Switch. By turning on the Audio Gating and Audio Presence Tally we enable a tally on the users' panels to show that audio is coming in to the FOR-22 from the radio.The Audio Detection Threshold is different for each system so these settings should be tested to match your hardware. The Audio Detection Off Delay is the length of time that the tally will be present on the users panel AFTER the audio has stopped exceeding the threshold.