diff --git a/wetb/signal/tests/test_fix.py b/wetb/signal/tests/test_fix.py
index 67983b334f8180f872f4a8273c6974927d70c577..c8b472a21544fe61ff27f5289c637e7834f9bcd5 100644
--- a/wetb/signal/tests/test_fix.py
+++ b/wetb/signal/tests/test_fix.py
@@ -27,6 +27,7 @@ class TestFix(unittest.TestCase):
         err_sum = np.sum((rpm_pos - ds.Rot_cor)**2)
          
         self.assertLess(err_sum,40)
+        self.assertLess(np.sqrt(np.mean((((ds.azi-rp_fit)+180)%360-180)**2)),2)
         if 0:
             import matplotlib.pyplot as plt
             t = ds.Time-ds.Time[0]