As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW WAS ATTEPMTING TO VERIFY FUCNTIONALITY OF WEATHER RADAR. WHEN ADJUSTING TILT AND GAIN, SMOKE IMMEDIATELY BEGAN POURING INTO THE COCKPIT FROM BENEATH THE WEATHER RADAR INDICATOR. AN EMERGENCY WAS DECLARED, AIRCRAFT LANDED WITHOUT INCIDENT. MAINTENANCE REMOVED RADAR INDICATOR AND FOUND THAT IT SMELLED BURNT.