What was found
NR 2 RADAR ON CAPTAIN'S SIDE WILL NOT PAINT GROUND RETURNS OR WEATHER. NR 2 RADAR ON FIRST OFFICER'S SIDE WILL NOT PAINT GROUND RETURN OR WEATHER AND RADAR SPIKES. AIRCRAFT RETURNED TO DEPARTING BASE. REMOVED AND REPLACED NR 2 RADAR TRANSCEIVER IAW MM 34-00. PERFORMED OPERATIONAL CHECK SYSTEM IAW MM 34-41-0; FOUND NORMAL. REMOVED AND REPLACED RADAR CONTROL PANEL SELECTOR IAW MM 34-41-0. OPERATIONS CHECKED BOTH POSITIONS, FOUND NORMAL IAW MM 34-41-0. AIRCRAFT RETURNED TO SERVICE.