Which of the following methods is used to locate sources of noise interference or jamming?

• A. Signal amplification
• B. Radio direction finding
• C. Frequency hopping
• D. Signal encryption

Answer: (B)

The method used to locate sources of noise interference or jamming is radio direction finding. This technique utilizes an antenna system and signal processing to determine the direction from which a radio signal is coming. By analyzing the received signals from multiple positions or using directional antennas, it becomes possible to pinpoint the source of interference. This is particularly useful in identifying unwanted noise in the radio spectrum, which can severely impact communication.

Signal amplification, while beneficial for enhancing weak signals, does not provide any information about the source of noise or jamming. Frequency hopping is a method used to minimize interference by rapidly switching frequencies within a defined range, but it does not itself locate interference sources. Signal encryption, on the other hand, is intended to secure communications, and has no role in detecting or locating interference. Thus, radio direction finding stands out as the most effective method for identifying the origins of noise and jamming in radio communications.