Once my alarm is set, its goes off with an outside siren, the second they cross the beam at the end of the drive. I also stayed here for weeks to catch him. That idea almost back fired, when I open the door cause someone was on my porch... I had a pistol in my hand and so did the 2 cops on the porch. We had our guns pointed at each other. I said... " you scared the heck out of me"... he said, you did the same to us!