Why is surveillance camera also called closed-circuit?
It is broadcast in the air by radio. It can not be called a closed circuit. Just like the radio can receive the same. The closed circuit can only be seen in your home or on your own. It is called a closed circuit
Yes, it can be understood, because it can only be used in a certain space, just like the VOD system in KTV, CCTV, someone's home is not received, the cable is not closed.
