diff --git a/pyModeS/__init__.py b/pyModeS/__init__.py
index 1869275..bc491d9 100644
--- a/pyModeS/__init__.py
+++ b/pyModeS/__init__.py
@@ -1,5 +1,8 @@
 from __future__ import absolute_import, print_function, division
 
+import os
+import warnings
+
 from .decoder.common import *
 from .decoder import tell
 from .decoder import adsb
@@ -9,9 +12,6 @@ from .decoder import bds
 from .extra import aero
 from .extra import tcpclient
 
-# from .decoder import els        # depricated
-# from .decoder import ehs        # depricated
-
-import os
+warnings.simplefilter("once", DeprecationWarning)
 
 dirpath = os.path.dirname(os.path.realpath(__file__))
diff --git a/pyModeS/decoder/bds/bds40.py b/pyModeS/decoder/bds/bds40.py
index cf96cbe..181149f 100644
--- a/pyModeS/decoder/bds/bds40.py
+++ b/pyModeS/decoder/bds/bds40.py
@@ -121,7 +121,6 @@ def p40baro(msg):
 
 
 def alt40mcp(msg):
-    warnings.simplefilter("once", DeprecationWarning)
     warnings.warn(
         "alt40mcp() has been renamed to selalt40mcp(). It will be removed in the future.",
         DeprecationWarning,
@@ -130,7 +129,6 @@ def alt40mcp(msg):
 
 
 def alt40fms(msg):
-    warnings.simplefilter("once", DeprecationWarning)
     warnings.warn(
         "alt40fms() has been renamed to selalt40fms(). It will be removed in the future.",
         DeprecationWarning,