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BBV TELEMETRY SYSTEM
INTRO
BBV’s open-system approach to video transmission
and telemetry simplifies installation and operation. Their current range of
bespoke and off-the-shelf systems have the facilities to accommodate the latest
cameras and peripherals
COPY
Flexibility is the key feature on Building Block
Video’s current series of telemetry receivers and transmitters. BBV offer a
wide variety of configurations, that can be used as the basis of a remotely
controllable multi-camera systems and networks, or easily integrated into
existing set-ups, with a minimum of disruption. The core components are the TX
and RX transmitter and receiver units.
The TX transmitter range includes numerous options
with 1, 8 or 16 camera inputs, with or without alarm inputs. We’ve been looking
at the TX1000/16 RX 16-camera unit. The choice of receivers is equally broad, models
are available that can accommodate a range of pan/tilt mounting systems and camera
functions. We’ve been testing an RX300M receiver module, housed inside a rugged
weatherproof case and designed to work with the versatile Mitsubishi CCD 300
integrated colour camera. The transmitter communicates with receiver modules and
cameras over distances of 1 km (or more), via coaxial cable or an optional twisted
pair.
The TX1000 comes in two parts: all of the
controls are brought together on a tough, heavy-duty steel-cased keyboard; connections
to receiver modules handled by an equally robust rack or wall-mountable base
unit. The top surface of the keyboard is covered by a touch-sensitive membrane,
with all functions clearly identified. It has three connections: a pair of
coaxial cables carry the monitor video output from the base unit, which passes
through the unit to a video output socket, that goes to the to the main
monitor; the third lead carries a bi-directional RS-232 data link to the base
unit. This is terminated in a 9-pin D-socket. The keyboard has a DC socket for
a local power supply, when the keyboard is used remotely.
The base unit is a simple, functional design
with all of the video inputs and their associated outputs arranged into two
rows, on the top panel. It has two monitor outputs, and a second 9-pin D-socket
for an auxiliary keyboard. A set of screw-terminal contacts for alarm and relay
outputs are mounted in the bottom left hand corner of the panel, immediately
next to the IEC mains socket and on/off switch.
LAYOUT AND CONTROLS
The keyboard is a very straightforward design.
The camera selectors are in two rows in the top left hand quadrant. Below that
there’s a row of four function buttons, for selecting camera sequence, patrol,
preset and monitor modes (we’ll look more closely at what they do in a moment).
On the right side of the panel there’s another line of buttons, for the
on-screen display, programmable facilities and secondary camera functions
(wash, wipe, autopan and lights). Immediately beneath there’s three pairs of keys
for iris open/close, focus and zoom. To the left a button with a blue triangle activates
low-current contacts on a relay in the base unit. This can be used to flag an event
on a VCR recording, or trigger a video printer. On the far right are the four
pan/tilt buttons.
The program button calls up the main on-screen
menu display, that covers most of the unit’s set-up functions. These include
setting the sequence delay and enabling camera inputs. Camera/receiver inputs
can also be manually selected or deleted, using the sequence function and
camera select buttons. Other options include a self-test facility, that steps through
receiver functions, iris level programming, alarm settings (where fitted) and
patrol delays.
Each camera/receiver can be assigned up to 16
‘presets’ that includes pan/tilt position, zoom and focus actions. The patrol
feature strings presets together, stepping between each one after a preset
period, adjustable from 2 to 30 seconds, or randomly, at intervals of between 0
and 100 seconds. This operates in the background, irrespective of the
camera/receiver selected by the transmitter.
Depending on the receiver and camera
combination various key permutation can be used to adjust camera parameters. On
the system reviewed (with the Mitsubishi camera) they include adjusting
backlight compensation in 7 fixed steps, shutter speed (7 steps, between 1/50th
auto and 1/1,000th sec) and white balance (auto, indoor, outdoor and lock)
The RX300M receiver has been designed with
ease of installation in mind. Most connections, including the twisted pair
video/telemetry and power/control signals to the camera, pan/tilt head and auxiliary
components (wash/wipe, lights etc.) are handled by a pair of Wago connectors,
with powerful spring-loaded contacts that grip the bared ends of cables. An IEC
socket on the main PCB carries the local mains supply, and a pair of BNC
connectors carry video output and telemetry, to and from the transmitter. The system
auto-tunes the telemetry link and the launch amplifier is factory-set for cable
runs of 500 metres. Lift and gain controls next to the BNC connectors are
provided, for setting for optimum picture quality, when using longer or shorter
cables.
Built-in self-test and diagnostic systems check
the operation of the various functions; these can be activated locally, by
pressing a button on the receiver PCB, or by a menu option on the transmitter.
A pair of flashing LEDs on the receiver PCB give a basic indication of system
status, operation or error condition.
Most of the functions of the transmitter and
receiver are reasonably clear-cut, though the supplied instructions tend to be
somewhat vague in places and could usefully have gone into more detail, and
more fully explained a number of points, including aspects of sequence
programming and the operation of the preset and patrol facilities.
PERFORMANCE
Our review system worked flawlessly. We carried
out tests using various lengths of cable, from 5 to 100 metres, with no
noticeable change in image resolution or increase in noise on the longer runs.
In all instances camera functions operated perfectly. Video inputs are free-running,
and there may be a momentary jump at the changeover points, when the sequencer
is activated.
CONCLUSION
Installation of the transmitter and receiver
components should be reasonably painless in most cases. Operator controls are
logically laid out and they’re easy to use. Feedback from the on-screen display
is a trifle limited though and user-definable camera idents would certainly be
a step in the right direction. The connecting cable for the keyboard is rather
short, camera selector indicators on the keyboard wouldn’t go amiss and the
instructions need an overhaul, but overall the system has no serious foibles,
or disagreeable habits. It works well and it’s clear BBV have put a lot of
thought into the system’s design and construction.
BOX COPY 1
SPECIFICATIONS
TX 1000/16 Telemetry Transmitter
Features up
to 16 programmable presets, 16 presets per camera, variable sequence dwell
time, dual alarm outputs, menu-driven programming, wall or rack-mount, 2
monitor outputs, optional proportional joystick control
Connections video
in/out BNC (auto termination on loop-through), 9-pin RS232 (keyboard to base
unit & second keyboard), screw terminals (alarm contacts)
Power requirements 240 Volts AC 50Hz mains
Dimensions base
unit 415 x 175 x 30, keyboard 415 x 190 x 30 mm
Weight 3kg
(keyboard)
RX300M Telemetry Receiver
Features camera
controls (auto iris override, backlight compensation, shutter speed, while
balance, zoom lens), random pan, auxiliary outputs (wash, wipe, lights,
autopan)
Connections video
in/out (BNC), spring terminals (twisted pair output & camera connections)
Power requirements 240 volts AC 50Hz or 110 volts 60Hz
Dimensions 190
x 380 x 130 (boxed), alternate PCB only 108 x 220 x 38 mm
BOX COPY 2
PSI RATING
Product
Product design 8
Build quality 9
Electronics quality 9
Installation
Ease of installation 8
Set-up functions 8
Instructions 7
Manufacturer’s support 8
Operation
Functions 9
Ease of use 9
Performance
Image quality 9
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Ó R. Maybury 1996 1704
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