In tone transmission, what encodes the value in the signal?

In tone transmission, what encodes the value in the signal?

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

Answer: (D)

In tone transmission, the value is encoded by how long the tone lasts. A fixed-frequency tone is sent, but what carries the information is the duration of that tone burst. The receiver measures that on-time and converts it into the corresponding numeric value. This approach contrasts with other signaling methods: changing the tone’s amplitude or using a carrier would encode value differently, a digital packet would spread data as structured bits, and a continuous stream of binary bits represents data in digital form rather than through a single tone’s duration. The duration-based tone encoding is exactly what a pure audible tone, whose length represents the measurement, uses.

In tone transmission, the value is encoded by how long the tone lasts. A fixed-frequency tone is sent, but what carries the information is the duration of that tone burst. The receiver measures that on-time and converts it into the corresponding numeric value.

This approach contrasts with other signaling methods: changing the tone’s amplitude or using a carrier would encode value differently, a digital packet would spread data as structured bits, and a continuous stream of binary bits represents data in digital form rather than through a single tone’s duration. The duration-based tone encoding is exactly what a pure audible tone, whose length represents the measurement, uses.