diff --git a/src/de/dhbwka/java/exercise/classes/Radio.java b/src/de/dhbwka/java/exercise/classes/Radio.java
index 2a3244e..51d3921 100644
--- a/src/de/dhbwka/java/exercise/classes/Radio.java
+++ b/src/de/dhbwka/java/exercise/classes/Radio.java
@@ -12,9 +12,9 @@ public class Radio {
   }
 
   public Radio(boolean on, int volume, double frequency) {
-    this.on = on;
-    this.volume = Math.max(Math.min(volume, 10), 0);
-    this.frequency = Math.max(Math.min(frequency, 110.0), 85.0);
+    this.turnOn();
+    this.setVolume(volume);
+    this.setFrequency(frequency);
   }
 
   public void turnOn() {
@@ -26,17 +26,25 @@ public class Radio {
   }
 
   public void incVolume() {
-    if (this.volume < 10) {
+    if (this.volume < 10 && this.on) {
       this.volume++;
     }
   }
 
   public void decVolume() {
-    if (this.volume > 0) {
+    if (this.volume > 0 && this.on) {
       this.volume--;
     }
   }
 
+  private void setVolume(int volume) {
+    if (volume >= 0 && volume <= 10) {
+      this.volume = volume;
+    } else {
+      this.volume = 5;
+    }
+  }
+
   public void setFrequency(double frequency) {
     if (frequency >= 85.0 && frequency <= 110.0) {
       this.frequency = frequency;