diff --git a/ohmpi/hardware_components/raspberry_pi.py b/ohmpi/hardware_components/raspberry_pi.py
index 86c6f00a4a8c3005a0b4aceaecb31dc4e301bd2b..20540c910138aea95cde1623ec0cea7571aebb11 100644
--- a/ohmpi/hardware_components/raspberry_pi.py
+++ b/ohmpi/hardware_components/raspberry_pi.py
@@ -29,7 +29,7 @@ class Ctl(CtlAbstract):
         try:
             self.interfaces['i2c_ext'] = ExtendedI2C(4)  # 4 is defined
         except Exception as e:
-            self.exec_logger.warning('Could not initialize Extended I2C:\n{e}')
+            self.exec_logger.warning(f'Could not initialize Extended I2C:\n{e}')
         # modbus
         try:
             self.interfaces['modbus'] = minimalmodbus.Instrument(port=modbus_port, slaveaddress=modbus_slave_address)
@@ -40,7 +40,7 @@ class Ctl(CtlAbstract):
             self.interfaces['modbus'].serial.parity = modbus_parity  # No parity
             self.interfaces['modbus'].mode = modbus_mode  # RTU mode
         except Exception as e:
-            self.exec_logger.warning('Could not initialize Extended modbus:\n{e}')
+            self.exec_logger.warning(f'Could not initialize Extended modbus:\n{e}')
 
         platform, on_pi = get_platform()
         assert on_pi
diff --git a/ohmpi/hardware_system.py b/ohmpi/hardware_system.py
index 95eaad9afc5fd7bcc26ff9ee199dc7474bfc11c8..fc89074d2097c3f5928ce3d6110dad7179d00410 100644
--- a/ohmpi/hardware_system.py
+++ b/ohmpi/hardware_system.py
@@ -28,7 +28,7 @@ for k, v in MUX_CONFIG.items():
     for k2, v2 in MUX_DEFAULT.items():
         MUX_CONFIG[k].update({k2: MUX_CONFIG[k].pop(k2, v2)})
 
-TX_CONFIG = HARDWARE_CONFIG['tx']
+TX_CONFIG = HARDWARE_CONFIG['tx']  # NOTE: is TX_CONFIG needed or should we use HARDWARE_CONFIX['tx']?
 for k, v in tx_module.SPECS['tx'].items():
     try:
         TX_CONFIG.update({k: TX_CONFIG.pop(k, v['default'])})