|
BAXALL ZMX+CT16M4 COLOUR MULTIPLEXER
STANDFIRST
Sixteen into one does go… Baxall can prove it, with the advanced
ZMX+CT16M4 colour vision multiplexer. We take a close look at what this formidable
box of tricks can do
COPY
If you get a sense of deja-vu after seeing the ZMX+CT16 for
the first time you needn't worry, the front panel bears more than a passing
resemblance to the Vista NPX16e colour multiplexer from Norbain, reviewed in
the XX issue of PSI. However, that's about as far as the exterior similarities
go. Baxall has taken an altogether more conventional approach to case design,
housing the unit in a sturdy looking slate grey steel box, measuring 443 x 90 x
346 mm. (The NPX16e, you may recall,
was built inside a smart plastic case, that could almost pass for a piece of
up-market hi-fi equipment).
The core specification also sounds quite familiar; this
model can handle up to 16 camera inputs, like its cousin from Norbain it
features 'Triplex' processing, which allows simultaneous encoding, playback and
live monitoring. Each input has an associated alarm trigger, additionally each
camera has an individually configurable motion detector; it has multiple
monitor outputs, including analogue live, spot and multi-screen (full screen, 4
x 4, 3 x 3, 2 x 2, 2 + 8, 3 + 4, 1 + picture in picture). The latter also includes
freeze frame and manoeuvrable 2X electronic zoom. Other functions include full coaxial
telemetry control of a wide range of motorised pan/tilt heads and domes, and it
will decode and display multiplexed tapes recorded by a number of other
systems. Various sequential actions can be programmed using a macro function.
At this point the two product ranges start to diverge. The
ZMX+CT16 has a number of additional facilities, either not seen before, or
exclusive to this model range. At the top of the list is matrix operation, in
fact this is the first multiplexer to have this facility built-in. It enables
the CT16 to double its capacity, up to 32 cameras, by connecting it to an
expansion unit (ZMX+EXP32). The multiplexer can control a suitably equipped VCR
directly, via an RS-232 serial link, with a functional link to the multiplexer's
own control system. The unit is compatible with other Baxall products using the
Bax-net protocol, this allows for full system integration, with other devices
and peripherals.
The front panel looks a bit haphazard (a criticism we also
had with the Norbain unit); it breaks down into four basic areas. Along the top
is a row of 16 camera selector buttons, it would have been helpful if they had
indicator lights, as it is you have to rely on a small on-screen indicator to
tell which camera output is being displayed (more about that later). On the far
left there's a group of buttons responsible for mode selection (sequence, live,
record and play) plus alarm cancel, macro function programming and an alt/shift
key.
Next to that is a bank of camera controls for selecting
preset position, operating the focus, iris, zoom (motorised and electronic) functions
and enabling camera a telemetry. The circular blue button or 'joypad' in the middle
and the two blue keys next to it have a number of functions, including VCR
control and selecting items from the menu-driven on-screen displays. Finally,
on the far right is a collection of buttons for ancillary camera functions
(camera power, wash, auto-pan, lamps and wipe), plus display options for picture
freeze, monitor output and multi-screen display. The layout is a little muddled and it's by no means intuitive so
it pays to keep the operating manual close to hand.
In contrast the back panel is a model of clarity and should ensure
a quick and easy installation. Two rows of BNC sockets handle the video inputs
and output loop-through for each camera. Two RS-485 sockets and a 9-pin D-Sub
socket carry two way serial data for connection to external devices, networking
and PC control. The VCR video inputs and outputs are carried on BNC and S-Video
sockets. Five BNCs and an S-Video mini DIN socket are used for the monitor
connections, alarm connections are accessed via a 25-pin D-Sub and the
expansion unit has its own 32-pin socket. Power is supplied by an external universal
(100 - 240VAC) mains adaptor. For the record the ZMX+CT16M4 uses a Dallas 1202
clock chip and is year 2000 compliant. Inside the case there are just four PCBs,
two are concerned with the front and rear panels. All of the processing and
control electronics are contained on two densely populated boards mounted on the
underside of the top panel. A cooling fan mounted on the side of the case ensures
reliable operation under a wide range of environmental conditions.
SET-UP AND OPERATION
We cannot foresee any difficulties for installers in the
vast majority of applications; the manuals supplied with the multiplexer are
very detailed and contain all the information installers and end-users are
likely to want or need. All of the many and various set-up routines are contained
within a comprehensive on-screen display system. This has two levels of access,
using PIN coded security control. The Operator or Quickinstall menus cover time
and date display (plus summer/winter time change), camera sequencing and title
editing, VCR housekeeping and the alarm history or log.
The installer menu requires a second PIN code; this also covers
basic time and date set-up as well as more detailed alarm and camera functions.
They include sequence dwell times, video loss and camera groupings, alarm input
configuration and actions, macro recording (it can store 16 macros consisting
of up 32 keystrokes), and the activity detector.
The activity detector is unusually flexible and one of the
units key features. It analyses each camera input for changes in luminance
level; the level of activity can be controlled to ignore random or anticipated
movement and set to distinguish between activity and intrusion. Activity is
defined as changes in scene brightness; intrusion involves actual movement of a
subject or object within the scene area.
During set-up the monitor display is divided into a 16 x 16
grid of sensitised 'zones'. Each zone can be alternately enabled or disabled
and the alarm threshold or sensitivity can be set to one of ten levels. A
simple graph or 'activity bar' superimposed on the side of the display shows
the relative amount of movement in the picture, it is calibrated with three
zones (red -- alarm activation levels 1 to 10; grey -- activity but no alarm,
and black -- no activity), to assist in the set-up.
The camera set-up also contains a multitude of options, they
are signal gain or AGC for each input, field or frame input, and covert camera
selection for specifying which cameras may be viewed on the monitor. The outputs
from nominated cameras will still be recorded and can be enabled for activity
detection and alarm activation however. The installer menu also contains
options for changing passwords; the operator password can also be changed from
the Quickinstall menu.
Alarms can be triggered by either an external contact, video
loss or motion detection. Possible alarm responses are: exclusive or interleaved
recording of associated cameras, change in VCR recording speed, sounding an internal
buzzer, flashing front panel lamp and an on-screen indicator. Alarm events are
recorded and indicated during tape playback and two internal relays (max 30
volt AC/DC) are activated. Alarms can be cleared manually, automatically (1 to
250 seconds) or by contact closure on a keyboard or external switch.
The alarm history display details the alarm number and the
time and date of the event; a log of the 100 most recent activation's are
stored in a non-volatile memory. A lithium battery powered backup system
retains all set-up data; this normally lasts for between 3 to 5 years before it
needs to be replaced.
PERFORMANCE
Operator training is crucial; the control layout is not
especially user-friendly and it is quite easy to get the device into an unwanted
configuration, without any obvious means of getting it back to normal
operation. Camera titles are quite small and tucked into the corner of the
screen, it would have been useful to have some means of changing the display's
position and characteristics; the text is black, which can be obscured by dark picture
detail.
Although the camera inputs are subject to digital processing
there is no significant loss of detail, increase in noise levels or reduction
in colour accuracy of the image, as it appears on the video output. The quality
of the recorded image will therefore depend on the performance of the recording
device used, to this end both composite and Y/C (S-Video) outputs are provided
to suit a wide range of peripheral equipment.
SUMMARY
The CT16M4 has a number of points in its favour, not least
the fact that it is a tried and tested design with a familiar line-up of
facilities. The range of functions is very impressive, providing almost
unequalled flexibility and options on a multiplexer of this type. Video performance
is outstanding too, ensuring that what goes in comes out, placing the onus for picture
quality on the input and peripheral components, such as cameras recording
devices and monitors. The unit is solidly built and despite some misgivings
about the control ergonomics, day to day operation is reasonably straightforward.
PRODUCT SPECIFICATION
Power supply 12 VDC (AC mains adaptor supplied)
Weight 6.5kg
Dimensions 443 x 90 x 346mm
PSI RATINGS
Product
Product design 9
Build quality 9
Ruggedness 9
Operation
General functions 9
CCTV functions 9
Ease of use 7
Instructions 7
Manuf. support ?
Performance
Video quality 9
Switching 9
Audio n/a
---end---
Ó
R. Maybury 1998 1210
| 
