Can someone give me a rundown on CCTV for dummies?
Often times there are multiple cameras. They appear on one monitor, however. Is this a regular television with a type of adapter for the camera inputs or a special television all together?
Also, I’m curious about the recording device. I asked one business owner who said that his security camera plugs into a regular VCR. This doesn’t seem very efficient or the most logical idea since you are only able to record X amount of taping. Are there certain VCR type recorders that will automatically rewind the tape and continue recording? What is the average cost, if it exists?
Basically, I’m looking to know the basics of CCTV and security cameras. Thanks!!!
It’s a regular television. It might be a monitor, which is basically a regular TV minus the channel-changing mechanism, which isn’t needed in a closed-circuit application. (But given economies of scale, sometimes it’s cheaper to just use a regular TV.)
The multiple cameras go thru a switching device, which chooses which one displays on the screen. The switching can be manual, where the security guard pushes buttons to select one camera, or it may be automatic, where the system just switches to each camera in sequence for x number of seconds. And some of them have logic that recognizes movement in front of a camera, and automatically switches immediately to that one. (Might even automatically turn on the VCR, too.) Some switches have a mode where 4 to 6 cameras are shown on screen at once, one in each corner of the screen. The operator can switch to full-screen view on any one when something is noticed.
It’s a normal VCR, but using extra-long running tape, and recording at the slowest speed, often black & white only. (This gives a low quality recording, but it’s good enough for use in Court.) This can give 8 to 10-hours on a single tape cassette, which is long enough to cover overnight. During the day, there are people there to change the tape as needed.
Also, more advanced systems are now set up so the tape is NOT running continuously. The system moniters the camera output, and only turns on the tape if motion is detected. That way, a single cassette can easily cover longer periods.
After our first time lapse VCR died, I put an old TiVo in. That worked great. What I did was tell it to record from that input in two hour increments. (1:00 to 3:00, 3:00 to 5:00… for the whole day) and then repeat that sequnce each day. Then I told it once it was full (about thee days worth) to delete the oldest segment. So today when it would record the 3:00 to 5:00 block it would delete the oldest two hour segement. Worked out pretty nice.
Now, a DVR can be purchased as part of the camera system and can usually record each channel at the same time. Like t-bonham said the cameras are plugged into a swither which outputs a video signal to the monitor, either one channel on the whole screen, or the screen divided into (usually) 4 or sixteen areas. Then the output from the monitor would go to the recorder. So if you caught someone stealing something, you would hit a button to bring that screen to full size. Nowadays you can buy a DVR that’s also a switcher, but the big difference is that it can record each channel at ‘full size’ so even later when reviewing the video you can see any channel you want at full size instead of what you chose beforehand…That’s confusing isn’t it.
If you want to take a look at some of the products available, check securityandmore.com]
and if you have a Sams Club membership, they usually have some on display that you can play with.
CCTV can be set up the way you describe, but it doesn’t have to be. Multiple cameras can be shown on one screen by using a multiplexer… however, each camera can be played back individually using that same multiplexer. Usually, the VCR used isn’t a normal VCR, but a time lapse VCR that can be set up to record 24 or more hours on one tape, although DVR’s are now the standard for new professional installs.
DVRs are becoming cheap enougn now that there is no reason to use a VCR. I can’t remember the last time we actually installed one. DVRs also come with optional CD burners, so you can get video out of the device and leave it in place.
Also, some DVRs can be used as part of a computer network, and viewed remotely through an internet connection.