diff --git a/src/minimodem.1 b/src/minimodem.1
index 8835318..cbf0316 100644
--- a/src/minimodem.1
+++ b/src/minimodem.1
@@ -101,7 +101,7 @@ Transmit 100 baud tones from one computer ...
 .B minimodem --rx 100
 and receive 100 baud tones on another nearby computer.
 .TP
-.B minimodem --rx rtty
+.B minimodem --rx --auto-carrier rtty
 Decode amateur radio RTTY signals (listen near 14.085 MHz).
 .SH NOTES
 .B minimodem