diff --git a/SerialPort.cpp b/SerialPort.cpp
index 6713bc5..12c741c 100644
--- a/SerialPort.cpp
+++ b/SerialPort.cpp
@@ -353,7 +353,7 @@ void CSerialPort::process()
             break;
 
           case MMDVM_SET_FREQ:
-            sendAck();
+            sendACK();
             break;
 
           case MMDVM_CAL_DATA: