The TKR-851's high stability 1.5PPM (2PPM for TKR-751) TCXO modules, 100% duty RF power amplifier (25W output), integrated die-cast heat sink and forced-air cooling provide site-friendly, continuous operation. Repeaters can function as a base station or repeater backup unit to suit various applications. The built-in 16 channels are preset and selectable from a remote control utilizing the remote I/O connector or pre-programmed key on the front panel. The programmable function (PF) keys located on the front panel permit adjustment and testing of repeater sites. In addition, single priority scan is available when the unit is operating in simplex mode.