Rancho Bernardo-based LRAD Corp. said that it sold its first mass-notification device to the government of South Africa.

Authorities in that country are buying a 2-ton trailer unit with a long-range acoustic device that can send messages out in 360 degrees. Financial terms of the deal, announced July 28, were not disclosed.

The LRAD (Nasdaq: LRAD) 360XT model has an emitter that can send warnings out in a radius of 850 meters (about half a mile) while maintaining sound clarity. Battery power can keep the emitter working for 24 hours. The emitter is mounted on a 30-foot telescoping pole on a trailer that can be hitched to a pickup truck. The electronics can be operated by remote control.

LRAD said that 70 countries now use their long-range sound systems.

The business will report its quarterly operating numbers on Aug. 6.