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Controlling Home Security Cameras
Home homeowners will only requires a simple, easy to use control system that will integrate with their existing TV and VCR. A typical system would only have one security camera, monitoring the front door. When someone knocks on the door the homeowner can switch channels on his TV and see who is there without getting out of his/her chair. For this type of simple application homeowners don't want the hassle of getting out of their chair to view images on a dedicated CCTV monitor hidden in a cupboard or another room
When multiple home security cameras are installed some form of control is needed to switch between one camera and another. A number of options are available to carry out this task depending on your requirements and the depth of your pockets:
Sequential Switcher
The lowest cost method of viewing multiple security cameras. Most switchers can view each camera independently on the screen and can also be set to automatically sequence through the cameras at an adjustable preset rate (some have independent adjustments for each camera). As well as viewing live on the monitor the outputs can be recorded for future viewing.
NOTE: recorders will only record one camera at a time with these switchers or the sequenced views - they will basically record what you see on the screen at any one time.
These switchers work with black and white and colour cameras. Some monitors are available with built in switchers. If you are feeding the output directly to your TV you will need a separate switcher with a built in RF modulator.
Many systems are now available as complete kits which include: cameras, lenses, brackets, power supplies, cables with connectors (different lengths to suit), RF modulators and with monitors and recorders if required.
Quad Switchers
Quads are similar to switchers but allow the simultaneous viewing and recording of all four security cameras, by splitting the monitor screen into four sections and showing a separate camera image in each quadrant. Most quad systems also allow you to view individual cameras full screen. Quad switchers are available to suit black and white cameras or colour cameras and can incorporate other features such as time and date and camera title insertion. If you need to record full size images from all cameras in the system, regardless of what you are viewing (single camera or multi camera views), you will need a multiplexer along with a time lapse video recorder or a digital vide recorder.
Multiplexers
More expensive than quads, the complexity and cost of these units generally make them unnecessary and unsuitable for the average home. Multiplexers allow the recording of multiple full size camera pictures on to one VCR tape and the playback of a full screen picture of any single camera or group of cameras. Multiplexers come in various models for handling 4, 8, 9 or 16 cameras, in various forms of sophistication.
Video Recording
Many homeowners will use the low cost domestic VCR for recording the output of their home security cameras. The main drawbacks with these machines are: the slow take up time once activated (you could miss the action), the restriction on recording time, no time and date stamps and of course you may be using it with your TV for recording or playback purposes at the critical moment.
Time Lapse Video Recorders
Time lapse video recorders have come down considerably in price in the last few years and offer far greater versatility than the less expensive domestic recorder. Time lapse machines are similar to the domestic VCR but with a slower moving tape that records the camera pictures as snapshots at split second intervals depending on the machine and the record settings, typically 24 to 960 hours on an E180 tape. The longer the record setting, the longer the period of time between the individual snapshots. It is important to match the record mode to your particular security problem, for example in the 480 hour mode the cameras picture will only be recorded every 3.2 seconds whereas in the 72 hour mode the picture would be recorded every 0.5 seconds. If you were recording 4 cameras these time delays would be multiplied by 4. Too long a delay and you may miss some vital action. You should always strike a balance between the time intervals when you can change tapes and the amount of information you need to record (time intervals between frames).
As time lapse recorders put more strain on the tapes than domestic recorders, it is important to restrict the number of uses per tape to maintain the quality of the recordings.
Example:
Digital Video Recorders
These recorders digitally record camera images from one or more cameras (4, 8 and 16 camera versions) on to a built in hard drive. They are really a multiplexer and a time lapse VCR rolled into one, but with no tapes to wear out or change. Being digital they offer fast simple easy retrieval of information, simply select the time and date you want to investigate, press play and you have the recorded images instantly replayed on your screen. No more tapes to rewind, fast forward or change. Easier to use than your domestic VCR
A picture is worth a thousand words.
Additional information items and hundreds more tips on how to protect your family, are now available in our new (211 – A4 page) security and safety book 'How to Protect your Family and Belongings Now'
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