Transmission  SDL Security Limited  

The signal from the CCTV camera to the monitor is transmitted in a number of ways. For cable runs up to 250m seventy five ohm coaxial cable is used, however for distances up to 1 mile 'baluns' in conjunction with CAT 5 cabling is used instead.

Besides the ability to send images longer distances the quality of the image is also improved as the balun solution provides greater immunity to interference from other cables and equipment. To this end the balun solution is often also used for distances below 250m either with new Cat 5 cables or by using our customers existing Cat 5 infrastructure.

Cat 5 cables are also used as network cables for computers systems and as such many of our customers will already have Cat 5 cables installed around their buildings. This potentially provides a massive benefit to our customers as the existing cabling can be patched from the camera to the monitor at minimum cost and without the disruption of installing new cables. 

Radio CCTV products are also available from SDL Security Limited, and are used in circumstances where cabling is either not possible or too expensive. High resolution images are possible up to 300m dependant on site conditions, and multiple channels are available allowing several cameras transmitting over radio in the same area.

Microwave CCTV equipment allows high resolution images, audio, and alarm signals with up to 8 channels to travel up to 4Km, dependant on equipment and site conditions.