สอบถามเกี่ยวกับ Error หน่อย ครับ ขอบคุณครับ C#.net ... No overload for 'timer1_Tick' matchs delegate 'System.EventHandler'

DispatcherTimer dt = new DispatcherTimer();
// Constructor
public New()
{
	InitializeComponent();

	dt.Interval = new TimeSpan(0, 0, 0, 0, 1000);
	dt.Tick += this.dt_Tick;
	dt.Start();
}

private void dt_Tick(object sender, EventArgs e)
{
}

private void button3_Click(Object sender, EventArgs e)
        {
            timer1.Enabled = true;
        }

        private void timer1_Tick()
        {
            //Check network status
            Ping pg = new Ping();
            PingReply pr = pg.Send("192.168.18.152");
            label5.Text = "Server IP : " + pr.Address + "";
            if (pr.Address.Equals("192.168.18.152"))
            {
                label7.Text = "Status : Fail";
            }
            else
            {
                label7.Text = "Status : Alive";
            }

            Ping pg2 = new Ping();
            PingReply pr2 = pg2.Send("192.168.18.154");
            label6.Text = "Server IP : " + pr2.Address + "";
            if (pr2.Address.Equals("192.168.18.152"))
            {
                label8.Text = "Status : Fail";
            }
            else
            {
                label8.Text = "Status : Alive";
            }

            //do every 30 mins
            if ((DateTime.Now.Minute == 30) || (DateTime.Now.Minute == 0))
            {
                FTP_MNGT(1);
                FTP_MNGT(2);
                FTP_MNGT(3);
                FTP_MNGT(4);
            }
            else
            {
                label3.Text = "Date Time : " + DateTime.Now + " ";
            }
        }