The time from the start of one pulse to the start of the next includes which components?

The time from the start of one pulse to the start of the next includes which components?

• A. One pulse duration only
• B. One listening time only
• C. One pulse duration plus one listening time
• D. One pulse duration minus listening time

Answer: (C)

In pulsed systems, you emit a pulse for a finite duration and then listen for echoes for a set listening window. The time from the start of one pulse to the start of the next is the sum of the pulse duration plus the listening time, because the transmitter cannot fire again until the listening period ends. For example, if the pulse lasts 2 microseconds and you listen for 8 microseconds, the interval between starts of successive pulses is 10 microseconds. This total time also sets the maximum range you can detect in one cycle since a longer listening window means a slower pulse repetition. The other options miss either the emitted duration, the listening window, or incorrectly subtract the listening time.

In pulsed systems, you emit a pulse for a finite duration and then listen for echoes for a set listening window. The time from the start of one pulse to the start of the next is the sum of the pulse duration plus the listening time, because the transmitter cannot fire again until the listening period ends. For example, if the pulse lasts 2 microseconds and you listen for 8 microseconds, the interval between starts of successive pulses is 10 microseconds. This total time also sets the maximum range you can detect in one cycle since a longer listening window means a slower pulse repetition. The other options miss either the emitted duration, the listening window, or incorrectly subtract the listening time.