diff --git a/ohmpi/hardware_components/mb_2023_0_X.py b/ohmpi/hardware_components/mb_2023_0_X.py
index faa6f94c9f315bb612ea27f5d24fe84f46a7b75c..9d8e43b12759eefc1b3021753b585102b2e1a817 100644
--- a/ohmpi/hardware_components/mb_2023_0_X.py
+++ b/ohmpi/hardware_components/mb_2023_0_X.py
@@ -114,7 +114,7 @@ class Tx(TxAbstract):
         kwargs.update({'board_name': os.path.basename(__file__).rstrip('.py')})
         super().__init__(**kwargs)
         assert isinstance(self.connection, I2C)
-        kwargs.update({'pwr': kwargs.pop('pwr', SPECS['compatible_power_sources'][0])})
+        kwargs.update({'pwr': kwargs.pop('pwr', SPECS['tx']['compatible_power_sources'][0])})
         if kwargs['pwr'] not in SPECS['tx']['compatible_power_sources']:
             self.exec_logger.warning(f'Incompatible power source specified check config')
             assert kwargs['pwr'] in SPECS['tx']