diff --git a/send.py b/send.py
index 989ec12..a8b8d9b 100644
--- a/send.py
+++ b/send.py
@@ -1,9 +1,6 @@
-import subprocess as sp
 import numpy as np
 
-import os
 import time
-import signal
 import logging
 import itertools
 
@@ -14,20 +11,6 @@ import ecc
 import sigproc
 from common import *
 
-dev_null = open('/dev/null')
-
-def play(fd):
-    args = ['aplay', fd.name, '-q', '-f', 'S16_LE', '-c', '1', '-r', str(int(Fs))]
-    ret = sp.call(args=args)
-    assert ret == 0
-
-def record(fname):
-    args = ['arecord', fname, '-q', '-f', 'S16_LE', '-c', '1', '-r', str(int(Fs))]
-    p = sp.Popen(args=args)
-    p.stop = lambda: os.kill(r.pid, signal.SIGINT)
-    return p
-
-
 class Symbol(object):
     t       = np.arange(0, Nsym) * Ts
     carrier = [ np.exp(2j * np.pi * F * t) for F in frequencies ]
@@ -73,6 +56,8 @@ if __name__ == '__main__':
         modulate(sig, bits)
 
 
+    from wave import play, record
+
     r = record('rx.int16')
     start = time.time()
     p = play(fd)
diff --git a/wave.py b/wave.py
new file mode 100644
index 0000000..e0cb5e6
--- /dev/null
+++ b/wave.py
@@ -0,0 +1,18 @@
+import os
+import signal
+import subprocess as sp
+
+from common import Fs
+
+def play(fd):
+    args = ['aplay', fd.name, '-q', '-f', 'S16_LE', '-c', '1', '-r', str(int(Fs))]
+    ret = sp.call(args=args)
+    assert ret == 0
+
+def record(fname):
+    args = ['arecord', fname, '-q', '-f', 'S16_LE', '-c', '1', '-r', str(int(Fs))]
+    p = sp.Popen(args=args)
+    p.stop = lambda: os.kill(p.pid, signal.SIGINT)
+    return p
+
+