After completing a field exercise, what is the last step when securing the AN/PRC-77 radio?

The final step in securing the AN/PRC-77 radio after completing a field exercise is to turn the operating controls to clear the last frequency used. This procedure is vital as it ensures that the radio is not left on any operational frequency that could inadvertently lead to communication on an inappropriate or unsecured channel. By clearing the last frequency, it helps maintain operational security and prevents unauthorized access to sensitive communications.

Additionally, this step prepares the radio for future use by resetting it to a neutral state, reducing the chance of accidental transmission and conserving battery life. While securing the radio in its protective case and winding the antenna are important steps in the overall process, they follow the critical action of ensuring the radio is not operational before it is stowed.