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No, itís not a high-priced Scandinavian hi-fi system, or the latest video game console, this is a serious piece of surveillance kit, reallyÖ



Strange as it may seem, and all evidence to the contrary, there are no rules governing the external appearance of video surveillance equipment. Cameras are designed to be discrete, or obvious, depending on the application, but what about the ancillaries?  There seems to be some sort of unspoken consensus amongst manufacturers that everything connected with video surveillance Ė whatever its purpose -- must be housed in off-white, square cornered boxes and look as bland as possible. Perhaps theyíre worried operators will be distracted by a dash of colour? More likely itís just cheaper and easier to do it that way. The point is, when someone dares to be different, it really stands out, like this Vista vision multiplexer from Norbain.


Simply looking different isnít enough; this is a serious business for heavenís sake. So how well does this dramatically styled multiplexer stack up against itís less flamboyant rivals?  Once you get past the imaginatively contoured black case with its bright blue buttons, itís off to a very good start, if the feature list is anything to go by. There are two versions at the moment: the NPX16e, that weíre looking at here, has 16 camera inputs; a 10 camera variant is also available (NPX10e), though you can take it as read that apart from the number of video channels, operationally and functionally they are identical.


Both models operated in what Vista describe as Triplex mode. It has nothing to do with car windscreens but indicates that it a notch up on conventional duplex multiplexers, which can simultaneously playback a multiplexed tape, and continue recording (on a second VCR). Triplex operation means the NPX16e can display live images and playback off-tape recordings on one of its two monitor outputs, and continue to record, all at the same time.


The Triplex facility utilises one of the NPX16eís seven multi-image display modes. The options are PIP (picture in picture) with a moveable sub-screen superimposed on a full-screen image. Thereís a conventional quad (2 x 2) display with the screen divided into four. The 7-way display is similar to the quad, except that one of the quarter screens is further sub-divided into four. A 9-way or 3 x 3 display shows nine images. The 10-way screen is a quad display with both lower quarter-screens divided into four. A 13-way screen is a quad with three of the quarter screen showing quad images, and lastly, thereís the 16-way or 4 x 4 screen, showing all connected inputs. 


Each video channel has an associated alarm input that, if activated, closes a relay and modifies the recording sequence. This uses a technique known as time division multiplexing whereby the output from a triggered camera, (or cameras), are recorded more often than the other cameras. Additionally each camera channel has its own motion detector alarm system. This will also alter the recorded sequence if activated, to favour cameras where activity has been detected.  The motion sensor divides the screen into a 16 x 16 grid of 256 sensor zones, which can be alternately enable or disabled. The motion sensor facility can be used in one of two ways, to discriminate between activity (changes in luminance) and intrusion (movement). In addition each camera has 10 levels of sensitivity plus a three-level false alarm rejection setting.   


All connected cameras can be sequenced and displayed on the two monitor outputs, dwell time is variable. Monitor B shows only a full frame analogue image from the sequence or the output from an alarm activated camera. Monitor A displays a single or multiple image, the Triplex display and the on-screen menu.  Other important features include an electronic zoom (more about that in a moment) and an activity log that records details of the previous 100 events. The unit generates a camera ident for each channel and it has a built-in telemetry transmitter, to remotely control camera focus and iris, plus PTZ (pan/tilt and zoom) functions and installations with lights and wash/wipe facilities.


The on-screen display and set-up routine are password protected, mono and colour camera operation is automatically selected. Up to 32 functions can be sequenced and controlled by a simple two-button command using a macro programming facility (macros can also be triggered by an alarm activation). Each camera has itís own AGC setting and a video loss alarm. Summer and Winter time changes can be made using a single button and thereís an option to connect the NPX16e to a radio time receiver, controlled by the Rugby atomic clock. All user-programmed settings are protected against power failure by battery-backup. 


Thereís no doubt that it is a very unusual looking case, itís a two part moulding made from ABS plastic, and measuring 460 x 88 x 390mm. The flat top is just the right size and strong enough to support one or more time-lapse VCRs. The highly distinctive front panel is populated with bright blue buttons, several of them with adjacent LED indicators.


Control layout is borderline haphazard. Thereís no problem with the row of 16 camera buttons along the top edge, though they could do with activity indicators, rather than having to rely on the on-screen idents, which can be very small on a multi-screen display. Some of the keys do not seem to follow any clear pattern. On the left side there are controls for macro programming, operating mode and camera functions. In the middle thereís a large blue button thatís responsible for cursor control on the on-screen display, and pan/tilt action. To the right of that is a mixture of picture controls (freeze, multi-screen) and housekeeping functions, like camera wash/wipe and lamps on/off and monitor select. You can learn to live with it, but thereís a distinct feeling that it could be a lot better. 


In case youíre interested, inside the box there are four printed circuit boards, the

Two largest ones are in the middle of the cabinet, one on top of the other. They deal with video processing the alarm functions and power regulation. Thereís a smaller PCB at the rear, this handles all of the input and output connections, and the board at the front is for the controls and indicators. Everything looks reasonably easy to get at, surface mount components are used throughout, for maximum reliability, and it runs cool, thanks to a small, and reasonably quiet fan on the right side of the case.



After the multiplexer has powered up and run through a brief self-test, a 4 x 4 display appears on monitor output A, showing all active camera inputs. A multiplexed output of all video channels appears on the VCR output. To change any of the default settings it is necessary to enter a simple password to access the menu-driven on-screen displays. Page one covers all of the main options, selections are made with a moving cursor (via the big blue button); pressing the 'Enter' button normally brings up a second or third sub-menu, from which various options can be selected. Key set-up operations include setting the time and date, enabling active camera inputs, creating camera idents, setting up any motion detector zones, alarm and video loss actions, VCR set-up and camera AGC. Navigating around the menus is quite easy, though some operations can be a bit time-consuming.


Most non menu-controlled operations are either straightforward or self-explanatory, though the slightly eccentric control layout can sometimes lead to confusion. The instruction manuals can be a bit heavy-going at times, the information is all there, but finding it can sometimes be a problem.


There are two basic operating modes: only the outputs from alarmed cameras are recorded in the Exclusive mode, whilst all camera outputs are recorded in Interleave mode. During off-tape playback the unit shows a multi-screen image of all cameras, from there a single image can be chosen, or any one of the multi-screen options. The electronic zoom feature is unusual; this works on a live recorded or frozen picture. Pressing the zoom button magnifies the displayed image by a factor of 2X; the pan and tilt control can then be used to view any part of the picture.


Alarm activation, whether from one of the external inputs or via a camera motion sensor, switches the display on monitor A to full screen (or quad, if more than one alarm is triggered). Monitor B switches to the output from the alarmed camera. The sequence of images that are passed to the recording VCR are changed to increase the number of times the output from the alarmed camera is included. At the same time an internal buzzer sounds, an on-screen indicator appears, a warning LED flashes on the front panel of the multiplexer and one of two relays are energised.  There are various alarm-reset options. It can be set to latch, so that it can only be cancelled by an operator.  Alternatively it can be set to time-out (unless the alarm condition remains), or set to transparent mode, where it will automatically clear, once the alarm input has ceased. The second alarm relay is activated by a loss of video on any one of the camera inputs, or by a motion detector.



Despite all of the heavyweight digital video processing going on inside the box there is no noticeable reduction in resolution, or any significant increase in picture noise, between the video input signal and the output, to the recording VCR. Picture stability and colour fidelity are both very good indeed, though we did notice a very small decrease in colour contrast. When camera outputs are viewed in the live mode thereís a choice of field or frame-rate display; some flicker is evident in the frame mode, which can be quite distracting, and tiring to watch for more than few seconds at a time.


In the end any degradation in picture quality will be caused by the recording VCR. The NPX16e does have Y/C (S-Video) outputs for the monitor and a Super VHS VCR, though in order to get full benefit from Y/C processing, the camera should be included in the Y/C signal processing chain as well. However, since the NPX16e only has composite/CCIR inputs, some of the potential improvements that would result from the use of high-specification cameras, are lost.



When it comes down to it the cosmetics of a particular device or piece of surveillance equipment are secondary to performance; nevertheless, thereís a lot of truth in the old adage that when something looks right, it usually is. The shape and styling of the NPX156e may be a little unconventional, but it does look right and it is completely practical. The extra frills and colourful buttons do not in any way detract from its real purpose. As multiplexers go it is an advanced design, with above average flexibility and performance, plus numerous extra features, that can only enhance its operational capabilities.   




Power supply              12 VDC (AC mains adaptor supplied)

Weight                        4.5kg

Dimensions                 460 x 88 x 390mm






Product design 9

Build quality               9

Ruggedness                8



General functions            9

CCTV functions            9         

Ease of use                 7

Instructions                7

Manuf. support            ?                     



Video quality              9

Switching                    9

Audio                          n/a


” R. Maybury 1998 1603




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Copyright (c) 2005 Rick Maybury Ltd.