diff --git a/MultiNode/MNLib.cpp b/MultiNode/MNLib.cpp
index 2db0ebf..95666ec 100644
--- a/MultiNode/MNLib.cpp
+++ b/MultiNode/MNLib.cpp
@@ -196,7 +196,13 @@ void loadMemory()
 
 void refreshConfig()
 {
-  radio.setFrequency(configuration.modem_frequency);
+  float frequency = configuration.modem_frequency;
+  
+  if (MODEM_FREQ_LOWER < value && value < MODEM_FREQ_UPPER)
+    radio.setFrequency(configuration.modem_frequency);
+    
+  else
+    radio.setFrequency(0);
 
   // The default transmitter power is 13dBm, using PA_BOOST.
   // If you are using RFM95/96/97/98 modules which uses the PA_BOOST transmitter pin, then
@@ -308,7 +314,7 @@ bool receive()
         {
           case MT_Time:
             rtc_offset = server_message_id - RTC->MODE1.COUNT.reg;
-          
+
             if (server_message_id > message_id) // Ensure that IDs are sequential
               message_id = server_message_id;
 
diff --git a/MultiNode/MNLib.h b/MultiNode/MNLib.h
index ffb9586..28e40c6 100644
--- a/MultiNode/MNLib.h
+++ b/MultiNode/MNLib.h
@@ -12,7 +12,8 @@
 
 #define MODEM_CONFIG RH_RF95::Bw125Cr45Sf128
 #define MODEM_POWER 13
-#define MODEM_FREQ 868.0
+#define MODEM_FREQ_LOWER 863
+#define MODEM_FREQ_UPPER 870
 #define HASH_LENGTH 8 // 8 bytes
 
 #define RF_SS_PIN  1
diff --git a/MultiNode/MultiNode.ino b/MultiNode/MultiNode.ino
index 2fa2e7d..d0a8a86 100644
--- a/MultiNode/MultiNode.ino
+++ b/MultiNode/MultiNode.ino
@@ -124,6 +124,43 @@ void loop()
 
       case 's':
         saveMemory();
+        break;
+
+      case 'T':
+      case 't':
+        String in_str = "";
+        while (in_str != "END")
+        {
+          in_str = SerialUSB.readStringUntil('\n');
+          in_str.trim();
+          if (in_str[0] != '#')
+          {
+            in_str.toLowerCase();
+            in_str.replace("\t", " ");
+
+            while (in_str.indexOf("  ") != -1)
+              in_str.replace("  ", " ");
+
+            int space_index = in_str.indexOf(" ");
+            String option = in_str.substring(0, space_index);
+
+            if (option == "frequency")
+            {
+              float value = in_str.substring(space_index, in_str.indexOf(" ", space_index + 1)).toFloat();
+              if (MODEM_FREQ_LOWER < value && value < MODEM_FREQ_UPPER)
+                configuration.modem_frequency = value;
+              else
+                SerialUSB.print("Frequency out of range!")
+              }
+            else if (option == "power")
+              int value = in_str.substring(space_index, in_str.indexOf(" ", space_index + 1)).toInt();
+              if (2 < value && value < 20)
+                configuration.modem_power = value;
+              else
+                SerialUSB.print("Power out of range!")
+          }
+        }
+        break;
     }
   }
 
@@ -154,7 +191,7 @@ void loop()
   long next_tick_device_dt = next_tick_device - now_time;
   long next_tick_sensors_dt = next_tick_sensors - now_time;
   long min_delay = min(next_tick_device_dt, next_tick_sensors_dt);
-  
+
   if (min_delay > 1000 && !USBDevice.connected() && message_id > 1000000000) // Listen until the time is initialized
   {
     power_sleep(min_delay);