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DOMINEYE TV WATCHDOG
WHAT OUR EXPERTS SAY...
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.
DANGEROUS!
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.
PERFORMANCE
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.
OVERALL ASSESSMENT
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.
PRODUCT ASSESSMENT
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
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Ó R.Maybury 1996 1605
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