diff --git a/peyote/detector.py b/peyote/detector.py
index 45b4c95e1c3dba8889cffbc8f6648279bd3ecf7b..66138be017fce7f3b1c2e84291b97511b303c7ab 100644
--- a/peyote/detector.py
+++ b/peyote/detector.py
@@ -87,15 +87,16 @@ class Interferometer:
         signal = source.frequency_domain_strain()
 
         for mode in signal.keys():
-            det_response = self.antenna_response(source.ra, source.dec, source.geocent_time, source.psi, mode)
+            det_response = self.antenna_response(
+                source.ra, source.dec, source.geocent_time,
+                source.psi, mode)
 
             signal[mode] *= det_response
         signal_ifo = sum(signal.values())
 
         time_shift = self.time_delay_from_geocenter(
             source.ra, source.dec, source.geocent_time)
-        signal_ifo *= np.exp(1j*2*np.pi*time_shift*source.frequency_array)
-        #signal_ifo *= np.exp(-1j*2*np.pi*time_shift)
+        signal_ifo *= np.exp(-1j*2*np.pi*time_shift*source.frequency_array)
 
         self.data += signal_ifo