Glossary 12913 GlossaryAAPCO The Association of Public SafetyCommunications Officials.The APCO Project 25 standardscommittee (http://www.apcointl.org/)defined a digital radio standard. Thestandard is often referred to as ‘APCO’or ‘P25’.Cchannel In a conventional system, a channel is apair of frequencies used to transmit andreceive radio signals.In a P25 trunking system, a channel is agroup of radio users.controlchannelIn a P25 trunking system, the controlchannel is used by the trunking site to letthe radio units in the site’s coveragearea know when they can transmit theircall information.conventionaloperationIn conventional operation, the radio istuned to a programmed channel, andcommunicates with other radios eitheron that channel, or through a repeatersystem.
