A driveway alarm can be used as an extra form of security for your residence. For example, if you have a long driveway because you live far off of a road, the alarm will trigger when a vehicle passes the sensors and will relay a sound of your choosing in your home to alert you of a coming vehicle. It could also be used at a business to alert the owner that a package is about to be delivered or a new customer is coming. http://www.absoluteautomation.com/driveway-alarm.html
Homeowners and businesses can use wireless driveway alarms to let them know when a person or a vehicle has entered the driveway. This helps them prepare to welcome guests and respond to intruders. In the past, driveway alarms took long wires and some digging, but now that wireless technology works so well, sensors can easily be positioned where needed for both temporary and permanent use. When a vehicle passes the sensors, the people inside the house know that someone has arrived.
What do you see first when someone passes by behind you?
frequency.
frequency.
yes
Driveway security alarms are wireless transmitters and receivers that sense presence through infrared sensory. The transmitter is weatherproof and is generally fixed near the mailbox. They monitor movement in the driveway. A signal will sound when something passes into it, typically a car driving in or a person stepping out. The theory is similar to lights.
This is known as the Doppler effect. The pitch changes as the vehicle stops moving towards you, and starts to move way from you.
Porte-cochère or portecochere: a porch- or portico-like structure at a main or secondary entrance to a building through which a horse and carriage (or motor vehicle) can pass in order for the occupants to alight under cover, protected from the weather. Porte-cochères should not be confused with carports in which vehicles are parked; at a porte-cochère the vehicle merely passes through, stopping only for passengers to depart or alight.
As long as the vehicle passes an emissions test.
Overtaken? Hence the vehicle is approaching rapidly from behind. You are to slow down and move to the right side of the road in the U.S. as long as it is safe to do so. If there is a shoulder, you are required to pull on to the shoulder and stop your vehicle as long as it is safe to do so) until the emergency vehicle passes you. Basically, you are to yield the right of way to emergency vehicles.
Passes for non-commercial four wheel vehicles and RVs is $30 per vehicle. The pass will last for 7 days.