SAN FRANCISCO—The San Francisco Municipal Transportation Agency has announced the winners of the 52nd Cable Car Bell Ringing Contest.

The contest, which was held July 9 in Union Square, was divided into two divisions: one for cable car conductors and grips, and one for amateurs, who represent local media and organizations.

After a 30-second ring-off with defending two-time Bell Ringing World Champion Trini Whittaker, Byron Cobb won the professional division. Cobb competed against a field of five other professionals, all of whom had qualified for the finals in a closed competition held at the Cable Car Barn two weeks prior to the event.

In the amateur division, Scotty Bastable, manager of Agency and Corporate Development at CBS, won against three other competitors.

Both winners will receive trophies. Cobb will receive cash and other prizes, which may include gift certificates from Union Square merchants; Bastable’s winnings will be donated to the University of California San Francisco’s AIDS Research Institute.

According to the official rules, this “uniquely San Francisco tradition” required competitors to “recreate the atmosphere of an operator in service, featuring his or her best showmanship for customers coasting along San Francisco’s scenic cable car lines.”

A panel of 12 judges, each representing a local community, judged the competitors on their rhythm, originality and style. No props or accompaniment were permitted.