Modifies the way gains are auto set

ohmpi/hardware_system.py

@@ -179,13 +179,14 @@ class OhmPiHardware:
             # self.tx_sync.wait()
             # set gains automatically
             injection = Thread(target=self._inject, kwargs={'injection_duration': 0.2, 'polarity': pol})
-            tx_gains.append(self.tx.gain)
             # readings = Thread(target=self._read_values)
             get_gain = Thread(target=self.tx.gain_auto)
-            get_gain.start()
             injection.start()
+            get_gain.start()  # TODO: add a barrier to synchronize?
             get_gain.join()
             injection.join()
+            tx_gains.append(self.tx.gain)
+
             # v = self.readings[:, 2] != 0
             # current = max(current, np.mean(self.readings[v, 3]))
             # voltage = max(voltage, np.abs(np.mean(self.readings[v, 2] * self.readings[v, 4])))