diff --git a/eive_tmtc/tmtc/acs/acs_ctrl.py b/eive_tmtc/tmtc/acs/acs_ctrl.py
index 7c2f1c2..06a194c 100644
--- a/eive_tmtc/tmtc/acs/acs_ctrl.py
+++ b/eive_tmtc/tmtc/acs/acs_ctrl.py
@@ -96,7 +96,7 @@ GPS_COURCE_DICT = {
     0: "NONE",
     1: "GPS",
     2: "PROPAGATION",
-    3: "SPG4",
+    3: "SGP4",
 }