/// <summary>
 /// Trigger für das Event 'System-Ereignis'
 /// </summary>
 /// <param name="e"></param>
 protected virtual void OnRaiseGsmSystemEvent(GsmEventArgs e)
 {
     // Make a temporary copy of the event to avoid possibility of
     // a race condition if the last subscriber unsubscribes
     // immediately after the null check and before the event is raised.
     RaiseGsmSystemEvent?.Invoke(this, e);
 }
 /// <summary>
 /// Trigger für das Event 'System-Ereignis'
 /// </summary>
 /// <param name="e"></param>
 protected virtual void OnRaiseGsmSystemEvent(GsmEventArgs e)
 {
     RaiseGsmSystemEvent?.Invoke(this, e);
 }