His technical career began when, at the age of 12, Stephen Dyer started his first business—a television repair service, which he expanded over the next few years to include analog-electronics design. At 14, he started an additional enterprise—in electroacoustics, involving design and construction of high-end sound-reinforcement loudspeaker systems. A year later, he also went into business with his brother, designing and crafting high-end consumer-audio systems and the fine cabinetry that housed them. Over those same years, he worked part-time as a technician for a firm that designed and installed commercial antenna-distribution systems. He later worked in the engineering department of Southwestern Bell Telephone Company, and as an electronics engineer in the research-and-development department of Seymour Machine Division.