What was found
(CAN) IN CRUISE AT FL 370, VHF 2 CONTROL PANEL GREEN LIGHT WAS INTERMITTENT, THEN BECAME EXTINGUISHED. CREW NOTICED AN ELECTRICAL SPARK FOLLOWED IMMEDIATELY BY A LIGHT WHITE SMOKE COMING FROM UNIT AT THE ACTIVE GREEN LIGHT. THE CREW PULLED THE ASSOCIATED CIRCUIT BREAKER AND INITIATED A DIVERSION TO AIRPORT WHERE A PRECAUTIONARY LANDING WAS CARRIED OUT. THE VHF NR 2 CONTROL BOX WAS REPLACED BY A MAINTENANCE CREW DISPATCHED FROM MONTREAL AND THE AIRCRAFT WAS SUBSEQUENTLY RETURNED TO SERVICE. A FOLLOW-UP WILL BE CARRIED OUT WITH THE MFG OF THIS AVIONIC EQUIPMENT TO DETERMINE THE CAUSE OF THE INCIDENT.