A coded alarm signal shall consist of not less than how many rounds of the number transmitted?

A coded alarm signal shall consist of not less than how many rounds of the number transmitted?

• A. Two
• B. Four
• C. Five
• D. Three

Answer: (D)

Redundancy in signaling is used to ensure an alarm code is understood even if part of the transmission gets distorted by noise or interference. When a coded alarm number is sent in rounds, repeating it at least three times gives the receiver enough independent copies to verify the pattern. If one round is garbled, the other two can still match and confirm the intended number. Two rounds could be ruined by a single disturbance, leading to misinterpretation, while more than three adds unnecessary delay without much extra reliability in typical systems. So, not less than three rounds provides a practical balance of reliability and efficiency.

Redundancy in signaling is used to ensure an alarm code is understood even if part of the transmission gets distorted by noise or interference. When a coded alarm number is sent in rounds, repeating it at least three times gives the receiver enough independent copies to verify the pattern. If one round is garbled, the other two can still match and confirm the intended number. Two rounds could be ruined by a single disturbance, leading to misinterpretation, while more than three adds unnecessary delay without much extra reliability in typical systems. So, not less than three rounds provides a practical balance of reliability and efficiency.