OVER-THE-COAX AUDIO FOR CCTV, A SOUND INVESTMENT
OVER-THE-COAX AUDIO FOR CCTV, A SOUND INVESTMENT
By: Don McClatchie
FM SYSTEMS, INC. Santa Ana, CA.
Tel: 800-235-6960
Hearing and speech are one of mankind’s most powerful tools. We rely heavily on the use of these faculties for our day to day living. Yet in the average security installation this audio information is not available to security personnel responsible for the safety and security of the facility. Having this audio information can speed the reaction time of security personnel, possibly saving lives and reducing law suits. This article will examine the opportunities and benefits provided by the use of audio for CCTV video.
The addition of audio to any CCTV camera installation magnifies the security of the facility. Security personnel will be alerted to danger in the observed area even if the danger is out of sight of the CCTV camera. Personnel will be alerted to security problems without having to observe them visually. A camera can only look in one direction at a time, but audio is omni-directional and picks up its sound information from all directions inside the security zone.
One example is an audio installation inside a parking garage. A person’s cry for help, the sound of an auto collision, or breaking glass would be noticed above the normal sounds of the garage. Security personnel can easily pick out a sound that is not normal from all the other sounds in the garage.
Two way audio has even greater benefit to the security of the facility. Personnel can respond verbally with people in the security zone. They can direct the actions of others or help guide rescue personnel inside the building without leaving the monitor control room. Unwanted intruders can often be persuaded to exit the premises without security personnel having to leave the monitor room. Emergency announcements can be made and compliance can be verified by the use of a video camera with two way audio.
An example of a two-way audio system, other than the obvious front door intercom is jail or prison cell surveillance and communication between guard buildings. Security is increased when the guards can communicate two-way.
The main problem with the installation of audio is the wiring process. Laying twisted pair wires along side the video cable is time consuming and labor intensive. For retro-fit installations the problem is complicated by having to trace the old video cables through the building. This makes it hard to estimate the labor required to complete the job.
Modern CCTV 2-way voice communication uses the existing coaxial cable, so no additional wiring is required. The 2-way audio travels on the same coaxial cable as the video picture and the video is unaffected by the audio signal. The audio follows the video where ever it goes. This makes retro-fit installations easy to estimate and build.
This new CCTV intercom technology also incorporates 2-way signaling or contact closures for remote control of doors, gates or alarm devices. Two way signaling allows the installer to wire a switch at the camera and control a contact closure at the monitor site. This can be used for a panic button, door bell or any device that needs a contact closure to operate. It allows someone at the camera to contact the monitor personnel and indicate which video camera they are near. Equipment such as the CAMERA-COM 2 has a built-in automatic volume control that lets you hear footsteps and shouts equally well. In a quite environment the volume is automatically turned up allowing security personnel to hear footsteps or other sounds where they don’t belong alerting them to security violations.
This new 2-way audio intercom technology allows the installer the ability to go back to old previously installed accounts and sell an audio upgrade without having to cut holes in the building or pull new coaxial cable. Installation time is reduced, and the customer can easily recognize the increased security and safety of the system. In many cases the addition of 2-way communication with the camera sites can reduce the number of security personnel required to monitor the facility. The customer will see the long term savings in the cost of personnel.
Audio surveillance for CCTV security is opening up a new horizon for security sales and installation. Dealers and installers looking for new products and services to sell to their new and existing customers should have a look at over-the-coax audio for CCTV video
