Security Installer

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To date CCTV has had a fairly limited impact on the domestic security market, that’s in spite of the widespread availability of several relatively inexpensive single-camera systems over the past five or six years. However, that’s about to change, thanks largely to the development of low-cost board cameras and a move away from dedicated monitors, to using an ordinary TV set, to display the camera image. Apart from making video surveillance a lot more affordable this approach makes the technology appear a lot less threatening, it’s also easier to install and use, to the point where several systems are being targeted at the DIY market.


The Domineye TV Watchdog is one of the most recent domestic CCTV systems to arrive. The manufacturers call it a ‘plug-and-go’ package, which sums up the simplicity of installation and operation. The outfit is attractively presented in a single box, it contains a camera module with built-in microphone and infra-red lights, weatherproof housing -- held together with tamper-resistant bolts -- 15 metres of multi-way cable and a TV modulator unit with on-board mains power supply. The box also contains an aerial cable plus a set of fixings, including screws and wall-plugs.


The camera is based around a single board module, with integral wide-angle lens, giving a 75 degree wide field of view; the vertical viewing angle is around 60 degrees. Either side of the lens there’s a row of three LED IR emitters, they provide enough light to illuminate a subject within a metre or so of the lens. An electret microphone is mounted just below the lens. In the base of the camera module there’s a small PCB containing power supply components and a 6-pin mini DIN socket.


On the back there’s a simple spring-loaded clip that attaches the camera to a moulded bar on the wall mounting plate, it has almost 180 degrees of horizontal movement, so it can be turned from side to side to get the best view. The front cover is made from red-tinted polycarbonate; this makes it almost impossible to see the camera inside, giving the unit an air of anonymity; it could be easily mistaken for a outside light. The cover held on by a pair of hex-headed bolts, it is tough and should be relatively vandal-resistant. The cover is not fully weatherproofed but it is sufficiently well protected for use in a porch or sheltered doorway.


The instructions talk mysteriously about the bottom half of the cover being designed to ‘enhance the sound collected by the camera microphone’. The fact is there are no holes in the cover, and sound is muffled, though the microphone is sufficiently sensitive for this not to be a major problem.


The camera unit connects to the TV converter by a the supplied cable, it’s terminated at both ends with mini DIN plugs. The cable could do with being a little longer -- 20 to 25 metres should cover most eventualities -- extra lengths can be added, though the instructions make no recommendation about the maximum length of cable runs.



The casing for the unusual-looking modulator/power supply module was clearly designed for some other purpose. There’s an odd-looking blanked-off circular cut-out and what looks suspiciously like a hole for a microphone. However, the real problem concerns the safety of the mains power supply inside, in particular the dangerous anchorage for the mains cable. On our sample the only thing preventing the cable from being pulled out of the casing was a 2.5mm cable tie. One light tug and it was free; any further tension on the cable would eventually result in the failure of one or more of the soldered joints holding the mains wires in place. This is clearly dangerous a dangerous state of affairs -- it’s inexcusable on any product, let alone one designed for a domestic environment -- the manufacturers must give this serious design flaw their immediate attention!


The converter is extremely simple to install. The modulator is fitted with an RF bypass; the downlead from the TV aerial connects to the unit, the supplied cable then goes to the TV’s aerial socket, or the RF input on a VCR. The modulator has a built-in test-signal generator, to simplify tuning, and the output frequency can be altered, to avoid cross-channel interference. The signal is used to tune in a spare channels on the TV (and VCR, if connected). Once installed the user simply selects the ‘camera channel’ on the TV, to see who’s calling. The VCR can record the picture and sound from the camera, a useful security facility, for householders who leave their homes empty for short periods, most domestic VHS VCRs will record for up to 8-hours in the LP mode, on an 4-hour (E-240) tape. 



Despite the heavily tinted camera cover low-light sensitivity is very good, quoted at 0.2 lux, without the benefit of IR illumination. It will certainly produce a useable image with just a simple porch light. The auto-exposure system, operates over a wide range of illumination, it copes reasonably well with bright lights within the scene area, and responds swiftly to sudden changes in lighting level. Resolution is in the order of 300 lines, though much will depend on the TV to which it is connected.  The wide-angle lens gives a good field of view, though there is a fair amount of barrelling at the sides. We were pleased by the lack of internal reflections, which can sometimes occur on housings of this nature. The microphone is very sensitive and will pick up a normal speaking voice up to a metre from the camera, though it can sound a little muffled at times. Some care needs to be taken with the placement. Wind noise can be a problem in gusty conditions as the mounting stands a few millimetres proud of the surface to which it is attached.



The design of the mains cable anchorage requires immediate attention, this product should not be sold in its present condition. However, that aside and apart from some slight misgivings about the cosmetics of the TV converter module, the general standard of construction is reasonably good. The combination of picture and sound, and the facility to monitor the output on an ordinary TV should have a lot of appeal for domestic users. Nevertheless, this is not an entirely new idea, and there are several rival systems on the market -- admittedly not so well protected or packaged -- that sell for substantially less.



Design and design features              3

Circuitry and components                  7

Ease of installation and wiring    8    

Range and variety of functions            7   

Accompanying instructions                   7          

Technical advice and backup            ?     

Value for money                         7                            




Ó R.Maybury 1996 1605




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