If a system uses tone transmission, which aspect carries the data?

If a system uses tone transmission, which aspect carries the data?

• A. A pure audible tone whose duration represents a measured value.
• B. A tone consisting of digital packets.
• C. A continuous stream of binary bits conveying the measurement.
• D. A radio frequency carrier with amplitude encoding the value.

Answer: (A)

With tone transmission, data is carried by the duration of the tone. A pure audible tone is emitted, and the length of time that tone is present encodes the measured value. The frequency or presence of the tone itself isn’t changing to convey the value—instead, the value is represented by how long the tone lasts. Other signaling methods would use digital packets, a continuous stream of binary bits, or modulation of an RF carrier, none of which match tone duration encoding.

With tone transmission, data is carried by the duration of the tone. A pure audible tone is emitted, and the length of time that tone is present encodes the measured value. The frequency or presence of the tone itself isn’t changing to convey the value—instead, the value is represented by how long the tone lasts. Other signaling methods would use digital packets, a continuous stream of binary bits, or modulation of an RF carrier, none of which match tone duration encoding.