Which of the following is required when making on-the-air test transmissions?

The requirement to identify the transmitting station during on-the-air test transmissions is fundamental to amateur radio operation. This practice aligns with the regulations set forth by the Federal Communications Commission (FCC), which stipulate that all amateur stations must furnish their call signs during transmissions. Identifying the station allows other operators to understand who is transmitting and maintain proper communication standards.

This requirement contributes to accountability and ensures that the airwaves are used responsibly. Identification also promotes good operating practices and helps prevent interference with others who may be using the same frequencies.

The other options related to conducting tests only during specific hours and notifying the FCC are not standard requirements for on-the-air test transmissions. While there are regulations regarding the hours of operation for certain types of broadcasting, amateur stations generally do not face such restrictions as long as proper protocols are followed. Additionally, there is no necessity to notify the FCC before conducting routine test transmissions, as such actions fall within the normal expected use of an amateur radio license.