What is important to check when using the "Sel SQ" feature on EF Johnson radios?

When utilizing the "Sel SQ" feature on EF Johnson radios, it is essential to check for selective quality, which ensures that the transmission and reception of signals are clear and without unwanted noise or interference. Selective quality refers to the ability of the radio to filter out other communications and focus on the desired signal, which enhances clarity during operations. This is particularly important in environments with multiple transmissions or potential interference, as it helps maintain effective communication and operational efficiency.

Other options available in the question may address different aspects of radio functionality, such as volume levels to ensure the sound is at an appropriate level for listening, signal strength to verify that the transmission is strong enough for clear communication, and channel clarity to ascertain that the chosen channel is free of noise and distortion. However, the unique focus of the "Sel SQ" feature specifically pertains to the quality of the selective reception, making attention to selective quality crucial for optimal use of the feature.