Quindar tones, most often referred to as the "beeps" that were heard during the American Apollo space missions, were a means by which remote transmitters on Earth were turned on and off so that the Capsule communicator (CapCom) could communicate with the crews of the spacecraft. It was a means of in-band signaling to simulate the action of the push to talk-release to listen (commonly referred to as PTT) button commonly found on walkie-talkies.
Read more about Quindar Tones: The Need For Quindar Tones, Implementation of Quindar Tones, Common Misconceptions About Quindar Tones, Origin of The Name
Famous quotes containing the word tones:
“This was Venice, the flattering and suspect beauty—this city, half fairy tale and half tourist trap, in whose insalubrious air the arts once rankly and voluptuously blossomed, where composers have been inspired to lulling tones of somniferous eroticism.”
—Thomas Mann (1875–1955)