Rescue and Coordination Centre - This is a centre used for coordination of all SAR activities within specified areas. When a RCC only is operating in the maritime Search and Rescue it's called a MRCC.
A receiver is a device, such as a part of a radio, television set, or telephone, that receives incoming radio signals and converts them to perceptible forms, such as sound or light.
Radio Telephony - Radio communication known as RT uses a Tx (radio transmitter) to send out radio waves of a certain frequency and a Rx (radio receiver) to receive the radio waves at the same frequency. Radio waves consist of electro-magnetic energy in specific frequency bands within the radio frequency spectrum. Frequency of waves means the number of occurrences of a wave per second. For example, marine VHF RT works in the VHF part of the marine radio frequency spectrum, which extends between 156 MHz to 174 MHz.