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The word 'system' strikes fear into the heart of many an installer or specifier, especially when applied to video surveillance equipment. All too often it means a manufacturer or distributor has cobbled together a collection of disparate components, and more often than not they will be the only ones to have ever got all of the parts to work in unison.  We're pleased to say that is not the case for Dedicated Micros new System Sprite, the key elements of which appear to have been designed from the ground up, to work together.


System Sprite is based around three components or 'building block's as DM like to call them. The core device is a multiplexer; several versions are available with 9 or 16 camera inputs. They can be used independently in a stand-alone configuration or used in conjunction with the second component, which is a keyboard unit. This controls all of the multiplexer's set-up and operational options and extends the system's functionality with telemetry control for remote cameras. Additionally it provides interface and control facilities for the third part of the system, a video switcher. The switcher enables any number of control points to be built into an installation, each one comprising a keyboard and a pair of monitors (main and spot). It also provides a simple upgrade path for increasing the size and capabilities of the system, up to an including a large-scale network installation with the potential to support several hundred cameras.


The multiplexers are housed in low-profile rack-mountable metal cases measuring 48 x 432 x 325mm (brackets are included). Apart from the number of input sockets on the back panel, camera selector buttons on the front and display options; the various models in the range are functionally identical. The headline features are single and multi-screen displays (full screen with single picture-in-picture, quad, 3 x 3, 4 x 4 and 10-way) picture zoom and multi-lingual menu display. It has multiple alarm options including external triggers and programmable activity detection. There's full duplex operation, user programmable camera titles, time/date displays and password protected system set-up. Additional convenience and performance related features include S-Video in/out to VCR, dual monitor outputs (main and spot), timer controlled detection periods, automatic daylight saving time switching. Connections to other components is handled by DM's proprietary 'C-Bus' (carrying RS485 serial data), which can be used to form the basis of a flexible and easily expanded network allowing up to 16 multiplexers to be linked together.


On the multiplexer's rear panel there are two rows of BNC sockets, for the camera inputs and outputs, monitor and VCR video connections. A pair of mini-DIN sockets handle S-Video signals to and from the VCR, a six-way plug-in connector block carries alarm relay and VCR control signals and two 'MMJ' telephone-style sockets are used by the C-Bus cables. Power comes from an external mains adaptor (90 240 VAC. 50/60 Hz input), which plugs into a multi-pin socket on the far left side.


A row of buttons on the panel is responsible for manual camera selection; pressing a selector button a second time enables the x2 electronic zoom facility. The four blue-coloured buttons on the far right double up as 'virtual' pan/tilt controls, shifting the area of the image displayed on the monitor screen. These buttons have a number of other functions, each one selects a monitor display mode (full screen, picture-in-picture, quad, multi-screen) and they act as navigation keys for the on-screen menu display. The menu is called up by pressing and holding the mode button on the far right of the panel. (The button's main function is to toggle between operating modes, i.e. record & playback).


The first page in the menu display covers time, date and language set-up. Menu 2 is for configuring the unit to work with a VCR, options include setting time-lapse and alarm parameters (Sprite is set to work with DM and Robot-type models by default) and to set the signal format (composite or S-Video). Menu page 3 is for setting up camera titles each one can be up to 12 characters long. Menu 4 selects the cameras to be recorded and menu 5 determines which cameras can be viewed. Menu 6 is used to specify detection periods for the alarms and activity detection system. The options are 'on' between set times, always on, always off and external or keyswitch control. Menu page 7 covers the alarm actions. There are options to set alarm dwell (0 to 999 seconds), main and spot monitor displays, playback display, alarm relay (close, open, always closed), alarm record (interleave for inserting alarm cameras in sequence, exclusive record alarm camera only and unchanged with all cameras recorded in sequence as normal).


The next menu (8) is for programming a preset camera position in the event of alarm activation and menu 9 is for selecting the display options (PIP position, quad sequence, time/date/text on main monitor & VCR output, text background and global sequence dwell). Menu page 10 deals with system options (setting ID number for networked Sprite units, menu password, and record lock, reset to factory defaults and daylight saving time set-up). Camera set-up is on menu. There are options for changing the title, setting input termination (on/off), alarm input connection (n/o, n/c, off), alarm module connection & ID, telemetry protocol (none, BBV, Pelco or DM DR4+/DTMF) and camera input (video detection alarm trigger on/off). The Activity System set-up is on menu 12, the options are dwell time (0 to 999 seconds), activity record method (interleave, exclusive, unchanged), activity record speed (time lapse mode), activity relay (close open, unchanged) and extended relay setting. Last but not least we come to menu 13, which configures the activity detection for each camera. There are five sensitivity settings (indoor high, indoor low, outdoor high, outdoor low and very low). The system uses an 8 x 16 detection grid, in the set-up mode the grid is superimposed on the image and each 'sensor' can be switched on or off using the camera selector buttons. There's an activity test option, to fine-tune settings before the system is enabled.


We move on now to the other components in the system. The keyboard controller is housed in a gently sloping case. On the back there's a single captive C-Bus cable. The top panel has four clearly defined banks of membrane type switches most of them have linked LED indicators -- and there's joystick for pan/tilt control of motorised cameras on the far right side. The keyboard duplicates most of the multiplexer's front panel controls (camera selectors, display mode, menu/cursor etc), plus there are a number of extra functions. These include a set of telemetry buttons for remote cameras, controlling zoom, focus, iris, wash/wipe, and lamps, auto pan and patrol functions. Also included in the telemetry control group of switches is a bright red coloured 'Panic' button, which manually activates the alarm relay. Additional features, not available from the multiplexer front panel are picture freeze/hold, system status, viewing the alarm log and system control, when the multiple Sprites are connected together. The keyboard is powered from its associated multiplexer (or switcher) via the C-Bus cable.


The third and last component is the video switcher, this also lives in a slimline case, similar in size (but styled slightly differently) to the multiplexer units. There's not a lot to see, the front panel is blank and on the back there are just two banks of camera input and output sockets (BNC), a pair of C-Bus sockets and a socket for the external mains adaptor. When a switcher is included in a system one of the C-Bus sockets is connected to a keyboard (or keyboards, via a junction box), the other C-Bus socket hooks up to the multiplexer. If more than one multiplexer is being used they are 'daisy-chained' together by C-Bus cables.


Build quality on all three components is very high indeed. The multiplexer has just two densely populated PCBs whilst the switcher box is mostly full of air; the single small PCB looks lost inside the almost empty box. All of the mechanical components, including the switches and joystick feel like quality items that should be able to withstand the rigours of daily use.



The instruction manual for the multiplexer is generally well laid out, reasonably easy to follow and quite well illustrated. The authors have made a valiant attempt to explain the various functions and we suspect that most experienced installers won't have too many problems with it. The switcher manual was clearly written by others, by comparison it's scrappy and disjointed, it's full of vital information but not especially helpful. Overall though, installation should be a doddle, thanks largely to the C-Bus, which makes it possible to upgrade or add system components in a matter of minutes, simply by plugging in extra modules.


Set-up can be a bit long-winded, though to be fair there's a lot of ground to cover. The menus displays could do with some tidying up, as it stands there's no easy way to move between pages, other than stepping through them in sequence, which is a mite inconvenient if you only want to go back a page or two. Selecting options is quite tedious as well, though you do eventually get used to the way it works. Nevertheless, we can't help feeling a single main menu with numbered selections would have made life a little easier. It becomes a lot more user/operator friendly when used with a keyboard, so much so that we consider this will be a near essential fitment on most installations. Incidentally, when the keyboard is connected it duplicates rather than overrides the local controls on a multiplexer, which continue to operate as before.



There's only one obvious omission from the otherwise very extensive range of set-up options and that's a facility to change the time/date and camera ID/titles. They're small and in fixed positions, which may not be convenient in some situations. At the very least it should be possible to enlarge or shift the position of the displays. As it is they are all uncomfortably close to the edge of the picture and could easily be masked or disappear altogether on a badly aligned monitor. 


The multiplexer and switcher are virtually transparent to the camera video inputs with no significant loss of resolution, colour fidelity or any increase in noise on signals passing through it. Live full screen images are largely free of any processing artefacts, indeed picture stability is excellent and there's no blurring or jerkiness when displaying rapid movement. Quad screen and multi-screen displays are also very steady and there's no loss of synchronisation when switching between display modes. 


Picture freeze is rock steady and although there is a noticeable reduction in resolution when using the electronic zoom there's no additional noise or loss of stability.



System Sprite has one or two relatively minor flaws, the displays and menus have some room for improvement but they do not detract from the main selling points which are in no particular order -- ease of installation, flexibility and the potential for upgrading and expansion. Most comparable systems have very clearly defined limits, beyond which they become unwieldy or unusable. System Sprite on the other hand has no such restrictions; from a functional point of view it appears to make no difference whether the system has 16 or 160 cameras. From the specifier and installer's perspective it's a dream come true, customers and clients can increase coverage and facilities virtually ad-infinitum, without having to scrap or replace kit, moreover System Sprite components can be just as easily integrated into existing systems.



Design and design features                      *****

Circuitry and components                *****

Ease of installation and wiring            ****

Range and variety of functions            ****

Accompanying instructions              ****                          

Technical advice and backup            ??    

Value for money                         ****                           



R. Maybury 1999 2907



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