Which of the following is an example of automatic control?

• A. Control from a computer network
• B. Repeater operation
• C. Direct human supervision
• D. Mobile station operation

Answer: (B)

Automatic control in the context of ham radio typically refers to systems that operate independently without the necessity for direct human intervention. This allows for consistent performance and reliability of communications services.

Repeater operation serves as a quintessential example of automatic control. A radio repeater receives a signal on one frequency and simultaneously retransmits it on another frequency. This operation is typically automated, meaning that once set up, it can run continuously without the need for someone to monitor or control it actively. The repeater can automatically reconfigure itself to respond to incoming signals, ensuring seamless communication for users without needing a human operator to manage the process.

Other options involve varying degrees of human intervention, which distinguishes them from the concept of automatic control. Control from a computer network may suggest some level of automation but often still requires supervision or commands from users. Direct human supervision inherently implies active monitoring and intervention, while mobile station operation primarily relies on the presence and actions of a human operator. These elements limit their classification as examples of automatic control.