diff --git a/ohmpi/hardware_components/mb_2023_0_X.py b/ohmpi/hardware_components/mb_2023_0_X.py
index 4a286a2b330df819ff5d93abf27ec8b03777eb33..f6a47d9353d278979ad88416007a6f034c72b282 100644
--- a/ohmpi/hardware_components/mb_2023_0_X.py
+++ b/ohmpi/hardware_components/mb_2023_0_X.py
@@ -208,7 +208,7 @@ class Tx(TxAbstract):
         if voltage is not None:
             self.pwr.voltage = voltage
         self.exec_logger.debug(f'Voltage pulse of {polarity*self.pwr.voltage:.3f} V for {length:.3f} s')
-        print('inject_mb')
+        print('inject_mb', polarity)
         self.inject(polarity=polarity, injection_duration=length)
         self.exec_logger.event(f'{self.board_name}\ttx_voltage_pulse\tend\t{datetime.datetime.utcnow()}')