PURPOSE: To realize switching from the current system to the standby system without short break by equalizing data strings, frame phases, and stuffing phases in the radio transmission equipment in the not standby system provided with at least a transmission code processing part having a redundant constitution.

CONSTITUTION: A reset means 3 resets the clock frequency divider of one system based on the output of a clock frequency divider of the other system, and thereby, data strings generated in serial-parallel conversion means 1a and 2a in transmission code processing parts 1 and 2 of the current system and the standby system coincide with each other. A frame timing signal generator in one system is reset based on the output of a frame timing signal generator of the other system to make the frame phases of both systems coincide with each other. Write clocks and read clocks are synchronized between both systems, and thereby, operations of phase comparators in both systems for stuffing coincide with each other to make the stuffing phases coincide with each other.