What was found
AFTER TAKEOFF, CREW EXPERIENCED WEATHER RADAR OPERATION INTERMITTENT WITH BLANK SCREEN AND ANTENNA FAULT MESSAGES. RETURNED TO HOU AND MADE AN UNEVENTFUL LANDING. REMOVED AND REPLACED ANTENNA DRIVE UNIT, NO HELP. INSPECTED, FOUND AND REPAIRED SHORTED DATA BUSS B-WIRE FROM R/T UNIT TO INDICATOR AND OPERATION CHECKED PER BOEING M/M OK.