A Pneumatic Ultrasonic Transmitter for a Low-Cost Remote Control

A pneumatic ultrasonic transmitter capable of generating a high-output 40 kc. tone burst has been developed and applied to a low-cost wire-less television remote control. Advantages over the more conventional transmitters, such as the struck gong or transistorized radiators, are economy, no batteries, higher output, durable construction, and ease of tuning. Because of the higher output, fewer and less expensive components are required in the receiver. Design parameters, circuit design, and operating results are discussed.