When the operator transmits on a circuit, it will illuminate which color?

When the operator transmits on a circuit, it will illuminate which color?

• A. Green
• B. Red
• C. Yellow
• D. Blue

Answer: (B)

Indicator lights on a communications circuit signal what mode the line is in. When the operator presses the transmit control, the circuit becomes active for sending voice, and a red light comes on. This immediate red cue tells others that the line is in use and that the operator is speaking, helping prevent interruptions and confirming that the transmission is going out. In many systems, receiving or idle is shown by green, while yellow or blue may indicate other statuses like standby or auxiliary channels, but those colors aren’t used to mark transmission. So red is the color that illuminates during transmission.

Indicator lights on a communications circuit signal what mode the line is in. When the operator presses the transmit control, the circuit becomes active for sending voice, and a red light comes on. This immediate red cue tells others that the line is in use and that the operator is speaking, helping prevent interruptions and confirming that the transmission is going out. In many systems, receiving or idle is shown by green, while yellow or blue may indicate other statuses like standby or auxiliary channels, but those colors aren’t used to mark transmission. So red is the color that illuminates during transmission.