What was found
CAPTAIN RADAR DISPLAY 2 FALSE LOBES AT THE 11 AND 1 O'CLOCK POSITIONS IN THE WX AND WX+T POSITIONS. GROUNDED-YES. AFTER ADIRU FULLY ALIGNED, CAPTAIN SIDE WXR RETURN WAS MASSIVE COMPARED TO F/O'S. NOTICED CAPTAIN SIDE GAIN WAS SET AT FULL MAX WHEN RETURN TO NORMAL CAL POSITION, BOTH SIDE DISPLAY SAME WXR RETURN. WXR SYSTEM OPERATIONAL TEST PASS, REF B737-900 AMM 34-43-00. NO HISTORY FPR WXR PAST 6 MONTHS, SEAMC MARK NOTIFIED.