A coded alarm signal shall consist of not less than how many rounds, and each round shall have not less than how many impulses?

A coded alarm signal shall consist of not less than how many rounds, and each round shall have not less than how many impulses?

• A. 3 rounds and 3 impulses
• B. 2 rounds and 4 impulses
• C. 4 rounds and 2 impulses
• D. 5 rounds and 5 impulses

Answer: (A)

In coded alarm signaling, the message is built from rounds, with each round being a burst of impulses used to convey the code. The standard requires a minimum structure to be reliably recognized, which means at least three rounds and at least three impulses in each round. This creates a nine-impulse pattern that’s distinct enough to be decoded correctly and provides redundancy against noise or misinterpretation. So the smallest configuration that satisfies the requirement is three rounds with three impulses in each round. Longer configurations would also meet the rule, but the question asks for the minimum, which is three rounds and three impulses per round.

In coded alarm signaling, the message is built from rounds, with each round being a burst of impulses used to convey the code. The standard requires a minimum structure to be reliably recognized, which means at least three rounds and at least three impulses in each round. This creates a nine-impulse pattern that’s distinct enough to be decoded correctly and provides redundancy against noise or misinterpretation. So the smallest configuration that satisfies the requirement is three rounds with three impulses in each round. Longer configurations would also meet the rule, but the question asks for the minimum, which is three rounds and three impulses per round.