diff --git a/owrx/source/hackrf.py b/owrx/source/hackrf.py
index 0f3855b..23ffcc8 100644
--- a/owrx/source/hackrf.py
+++ b/owrx/source/hackrf.py
@@ -11,6 +11,7 @@ class HackrfSource(DirectSource):
                 "rf_gain": Option("-g"),
                 "lna_gain": Option("-l"),
                 "rf_amp": Option("-a"),
+                "ppm": Option("-C"),
             }
         ).setStatic("-r-")