Doktor Jon's brief introduction to CCTV
Most people think that CCTV is a relatively new invention, but then again, some still don't even know what it is ... well, certainly in some of the further flung corners of the globe..
First things first, what exactly is Closed Circuit Television?
Well the television bit is perhaps self explanatory; it's simply about putting a picture onto a television screen, or 'video monitor' to give it the correct title. Incidentally, historically older basic video monitors were essentially televisions, but without the additional circuitry needed, to receive and decode the Radio Frequency 'TV' signals, which are normally transmitted through the air.
Now the 'Closed Circuit' bit is also quite straightforward.
Let's say for example, that you subscribe to Satellite TV. If you watch your favourite television programme, you and perhaps a few million others will be able to receive the transmitted signal through the dish and 'set top box'.
As anyone with a correctly tuned 'Telly' can access this signal, we can safely describe this type of arrangement as an 'Open Circuit Television' or 'OCTV' system.
Now if a signal is being linked from any source, whether it's a DVD player, a camcorder, or a surveillance camera, directly to a display device such as a television, this is described as a 'Closed Circuit' simply because it is not normally available to anyone else.
So you can see that in the early days of developing video surveillance security systems, the pictures from the cameras were almost always sent to a monitor, or a video recorder, or indeed a sealed Control Room under 'Closed Circuit' conditions, hence the now widely accepted term "Closed Circuit Television" or "CCTV".
Whilst the now widescale use of video cameras for security, has really only taken off in the last dozen years or so, the technology has actually been available in one form or another, for perhaps the last forty years (more background info. available in the "History of CCTV' section).
Now of course, "CCTV" cameras appear to be everywhere, and even domestic household cameras can be bought for very little cost; so the longterm development of security surveillance looks assured. 'Digital' and 'IP'' based network technology products provide opportunities for developing even more sophisticated "Network Surveillance" or "IP Video" systems. Also the gradual increase in availability of "HD" standard video surveillance equipment will undoubtedly impact on conventional "legacy" CCTV analogue systems, which are destined to gradually decline in popularity and usage over the coming years.
For the moment at least, analogue CCTV continues to outsell IP Video in the UK, although this situation is unlikely to continue for any great length of time.
IMPORTANT: No material may be reproduced, copied or redistributed from this site, without the express written consent of doktorjon.co.uk
All the detailed information on this site is provided in good faith; and as such, Doktor Jon does not accept responsibility for any consequential loss, injury or disadvantage resulting from any individual or organisation acting on the details contained herein.
© Doktor Jon 2004 - 2015
Please Note - Doktor Jon is currently upgrading his site, so you may see some layout changes on various pages, whilst the work is in progress. Hopefully, the total re-design and improvements, should be completed during 2015.
You're currently viewing Doktor Jon's introduction to CCTV - Original Content first listed - February 2004