Security Cameras for 4-Channel Audio Video Selector Circuit

CCTV system is a circuit prepared for you to monitor 4 points with a single monitor in camera security systems, there are some that are normally made without electronic circuits, but image and sound losses can be high with this circuit, the losses are almost non-existent. and -5v (ne555 negative converter) there are led indicators for the regulated system channels.

Monitor up to four security cameras on a single monitor. It automatically selects each camera in turn. Ideally, each camera in a CCTV system will have its own dedicated monitor, making it easy to watch and listen to all they see and hear. But video monitors are not cheap, and this approach is too expensive for most of us.

Fortunately, there is an alternative: just use one monitor with the so-called “AV sequencer” or “camera switcher”. This works like a multiplexer or scanner, it automatically cycles through the cameras so that the video and audio are output from camera 1 first, then camera 2, then camera 3 and so on. you get it. Each camera’s signals are presented in sequence for a few seconds, allowing you to keep an eye out for anything you’re interested in.

Of course, AV sequencers are commercially available, but while they are much cheaper than additional monitors, they are still quite expensive.

The circuit can handle video and audio from up to four cameras, and the scan rate can be adjusted in the range of about 10:1 to suit different applications. There is a row of LEDs on the front panel to show which camera is available at any given moment, and there is also a “Pause” button. This button allows you to stop scanning and concentrate on just one camera when you find or hear something of interest to the unit.

Audio Video Selector Project

Source: http://www.siliconchip.com.au/cms/A_101674/article.html

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