Why is the term Roger Wilco considered by some to be an incorrect phrase - trivia question /questions answer / answers
Aerophones; any class of musical instruments in which a vibrating mass of air produces the initial sound including bull roarers and sirens. They are found in many countries throughout Africa and are normally incorporated with dancing, the musicians having to synchronize their footwork along with playing their notes!
Aerodist master units essentially comprised: a klystron oscillator that set the carrier signal frequency that allowed voice communication with remote units, and later broadcast the measuring pattern frequency signals; a triode power amplifier that amplified carrier and measuring signals for transmission through the aircraft antenna system; and ovens for the crystals that determined the pattern frequencies that were automatically switched over the carrier frequency to give the measuring ...