diff --git a/pulse_lib/tests/mock_m3102a.py b/pulse_lib/tests/mock_m3102a.py
index 7218c9d176c545debd128af716969259b5063fad..486c1361e9072e0ead3db4ca5133d0f3b52f8736 100644
--- a/pulse_lib/tests/mock_m3102a.py
+++ b/pulse_lib/tests/mock_m3102a.py
@@ -28,6 +28,9 @@ class MockM3102A(Instrument):
         for prop in self.measure._ch_properties.values():
             prop.acquisition_mode = mode
 
+    def set_channel_acquisition_mode(self, ch_num, mode):
+        self.measure._ch_properties[ch_num].acquisition_mode = mode
+
     def get_channel_acquisition_mode(self, ch_num):
         return self.measure._ch_properties[ch_num].acquisition_mode