Intercom - Furuno FM-4800 Operator's Manual

Press and hold the PTT key to talk.
Step 3
Release the PTT key to listen to the response from the hailer.
Step 4
You can adjust the talking volume.
Press the Back key to return to the previous screen.
Step 5

8.3 Intercom

The Intercom feature allows the intercommunication between the radio and a
handset. This feature is available only when your radio is equipped with handset, or
a microphone.
On the home screen, press the Menu/DSC control to enter the "MAIN
Step 1
MENU" screen.
Go to "COMMUNICATIONS > INTERCOM".
Step 2
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