In tone transmission, how is the measured value conveyed?

In tone transmission, how is the measured value conveyed?

• A. A digital packet containing time-stamped data.
• B. A continuous stream of binary bits conveying the measurement.
• C. A pure audible tone whose duration represents a measured value.
• D. A radio frequency carrier with amplitude encoding the value.

Answer: (C)

In tone transmission, the value is encoded in how long the tone lasts. A constant-frequency, pure audible tone is produced, and the measured value is determined by the duration of that tone burst—the longer the tone, the higher the value, within the predefined scale. The receiver measures the elapsed time of the tone to decode the measurement. This fits the option describing a pure audible tone whose duration represents the value. The other ideas describe sending explicit digital data, a continuous stream of bits, or encoding the value by amplitude on a carrier, which are not how this tone-duration encoding conveys information.

In tone transmission, the value is encoded in how long the tone lasts. A constant-frequency, pure audible tone is produced, and the measured value is determined by the duration of that tone burst—the longer the tone, the higher the value, within the predefined scale. The receiver measures the elapsed time of the tone to decode the measurement.

This fits the option describing a pure audible tone whose duration represents the value. The other ideas describe sending explicit digital data, a continuous stream of bits, or encoding the value by amplitude on a carrier, which are not how this tone-duration encoding conveys information.