The IC-PAC interface cable provides DC power and control between the radio and the autotuner. Three Feet (36") Long This interface cable will work with any Icom radio that supports the Icom AH-3 or AH-4 Tuner. Please check your radio's manual Pressing the tune button quickly on the tuner by-passes the tuner. Pressing and holding the tune button on the radio or tuner starts the tune process. The IC-PAC and IC-PAC-6 interface cables providing DC power and control between the radio and the autotuner. Available in six foot (IC-PAC-6) and one foot (IC-PAC). Supported Radios: IC-7000, IC-7600, IC-7700, IC-7100, IC-7200, IC-7300, IC-706, IC-707, IC-718, IC-725, IC-728, IC-736, IC-738, IC-746, IC-756. This interface cable will work with any Icom radio that supports the Icom AH-3 or AH-4 Tuner. Please check your radio’s manual. Functionality: Pressing the tune button quickly on the tuner by-passes the tuner. Pressing and holding the tune button on the radio or tuner starts the tune process. Note: If you are using this cable with the IC-718, be sure to set the tuner menu to “4”. The LDG tuner and interface cable emulates the Icom-AH-4 tuner.