Marine Radios Review

Typically, communication can only take place in one direction at a time.  That is to say, you must transmit your message and then release the “transmit” button on your VHF radio and wait for the other person to respond.  The position of the “transmit button” (depressed or released) determines whether your unit is ready to transmit or receive communication.  This type of ‘one way’ communication is called “simplex”.  Now, there are “duplex” units available and the majority of the channels are set aside for this type of communication as it allows both receiving and transmitting simultaneously.  Weather, of course, still operates on a “receive only” mode.