Norton Commander (motorcycle) Norton Commander (motorcycle) The Commander was a Norton motorcycle with a Wankel rotary engine. The first Norton Wankel motorcycle was the 1987 air-cooled Classic, built as a special edition of just 100 machines. It was followed by the air-cooled Interpol 2 model. The Commander was a liquid-cooled successor to the Interpol 2, liquid cooling being adopted for greater power and reliability. The Commander's final-drive chain was protected by a full enclosure. Some cycle parts (such as front wheel, forks & brakes) were bought-in Yamaha items. Two types of Commander were built. The P52 was a single-seat model equipped for police
Tuning fork that vibrate in the magnetic field of a pickup, creating a signal that drives electric amplification. The earlier, un-amplified dulcitone, which used tuning forks directly, suffered from low volume. The quartz crystal that serves as the timekeeping element in modern quartz clocks and watches is in the form of a tiny tuning fork. It usually vibrates at a frequency of 32,768 Hz in the ultrasonic range (above the range of human hearing). It is made to vibrate by small oscillating voltages applied to metal electrodes plated on the surface of the crystal by an electronic oscillator circuit. Quartz is piezoelectric,