Radio Check – Check on signal strength. Can you hear me now?
Read you loud and clear – Responding to “Radio Check.” Transmission Signal is strong.
Go Ahead – Resume the transmission.
Roger or Ten Four – Message is received and understood.
Wilco – This means “I will comply.”
Affirmative – Yes.
Stand By – Acknowledges transmission, unable to respond.
Say Again – Re-transmit your message.
Negative – No.
Come in – Asking other party to acknowledge that they hear you.
Copy – Indicates that you understand what was just said.
Over – Transmission finished.
Out – Communication is over; channel is available.
Break, Break, Break – To interrupt a communication because of an emergency.