diff --git a/csdr/chain/rtl433.py b/csdr/chain/rtl433.py
index c15a608f..e34c20cf 100644
--- a/csdr/chain/rtl433.py
+++ b/csdr/chain/rtl433.py
@@ -1,4 +1,3 @@
-
 from csdr.chain.demodulator import ServiceDemodulator, DialFrequencyReceiver
 from csdr.module.rtl433 import Rtl433Module
 from pycsdr.modules import Convert, Agc