Frequency Electronics, Inc. (FEI) lets the good times roll. The company makes quartz-, rubidium-, and cesium-based time and frequency control products, such as oscillators and amplifiers, used to synchronize voice, data, and video transmissions in satellite and wireless communications. The US military uses its products for navigation, communications, surveillance, and timing systems in aircraft, satellites, radar, and missiles. Though FEI has diversified into commercial markets, more than half of its sales still come from the US government. Other top clients include Lockheed Martin, Northrop Grumman, AT&T, and the State of California. The company was formed in 1961 as a time and frequency control R&D firm.