diff --git a/test_sigproc.py b/test_sigproc.py
index 6cf8750..33f553d 100644
--- a/test_sigproc.py
+++ b/test_sigproc.py
@@ -6,7 +6,7 @@ import random
 
 
 def test_qam():
-    q = sigproc.QAM(sigproc._symbols)
+    q = sigproc.QAM(common.symbols)
     r = random.Random(0)
     bits = [tuple(r.randint(0, 1) for j in range(4)) for i in range(1024)]
     stream = itertools.chain(*bits)