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CW-4871, -72, -73, -74, -75, -76, -78 DEMODULATOR QUAD
KÁBEL-TV RENDSZEREKET GYÁRTÓ ÉS FORGALMAZÓ MAGYAR - AMERIKAI KFT.
A HUNGARIAN - AMERICAN LTD. COMPANY FOR MANUFACTURE AND SALES OF CABLE TV EQUIPMENT
CW-4000
DIGITAL TELEVISION DEVICES
CW-4871, -72 QPSK DEMODULATOR
Budapest XI., Kondorfa u 6/B
Hungary
Ltd.
E-mail: [email protected]
Tel.: ++36 1 204 7815
Fax: ++36 1 204 7839
Internet: www.cableworld.hu
CW-4873, -74 QAM DEMODULATOR
CW-4875, -76 OFDM DEMODULATOR
CW-4878 ASI DESCRAMBLER
Dear User!
Digital technology forms our environment day by day,
and we can enjoy its advantages in more and more fields
everyday. These are the years, when digital television technology takes over the leading role, thus it is time to get it
know and make preparations to use it.
CableWorld Ltd. has carried on developing activity in
the field of digital television for several years. Its aim is to
create a transparent, versatile and universal system, which
makes this complex and complicated technology for both
engineers and other technicians as manageable and lucid as
analogue technology was.
The input units of the digital headend receive signals
coming from satellites, cables and terrestrial transmitters,
and convert them into transport stream signals.
The transport stream is nothing else as a vast data
stream consisting of numerous elementary streams. A part of
these streams carries picture-, sound- and data signals.
The CW-487x series input units consist of 4 independent receiver units each, all having ASI outputs.
The connecting link between the pieces of software and
hardware is the CW-Net Data Transmission and Device
Control System.
1. MECHANICAL CONSTRUCTION
The CW-4871 and -72 QPSK Demodulators, the CW4873 and -74 QAM Demodulators and the CW-4875
and -76 OFDM Demodulators and CW-4878 ASI
Descrambler are built in standard 19" × 1 HU instrument frame. They are delivered along with following
accessories:
1. Power cord 1 ea.
2. Spare fuse T1.25 A for CW-4871, -73, -75 and -78 1 ea.
T2.5 A for CW-4872, -74, -76 1 ea.
(placed in the fuse holder mounting)
3. Crossover cable with RJ45 connectors 1 ea.
The power consumption of the devices is very low
therefore no cooling or ventilation is needed.
USER’S GUIDE
2. ELECTRICAL CONSTRUCTION
The CW-4871 and -72 QPSK Demodulators process the signals coming from satellites, the CW-4873
and -74 QAM Demodulators process the signals
coming from cable networks, whereas the CW-4875
and -76 OFDM Demodulators process the signals
coming from terrestrial transmitters, and CW-4878
ASI Descrambler processes the transport stream
(ASI signal). All 7 types consist of 4 receiver units
each, and all receiver units have double ASI outputs.
The devices are equipped with an own switching
mode power supply. The supply voltage of the interface circuits is +3.3 V, but the signal processing circuits are supplied with a voltage as low as +1.8 V.
The power consumption of the devices is low, and
they are suitable for continuous service.
All types are put in operation in the same way.
1. Connect the device to the computer through
crossover cable.
2. Set the device to the desired IP address.
The devices are shipped with IP address set to
10.123.13.101. When using in network, the IP address
must be changed to avoid conflict between the IP addresses of multiple devices.
For changing the IP address download, install and
use the SW-4800 software. All knowledge necessary
for this are included in the Help file of the software.
After having installed the software, run it by clicking the
CW-Net Principal icon, and in the IP Address Platform
change the IP address of the device. In this example let
the new address be 102 instead of the 101.
3. Install software corresponding to the type of the
device:
SW-4871 for the CW-4871, -72* QPSK Demodulator Quad
SW-4873 for the CW-4873, -74* QAM Demodulator Quad
SW-4875 for the CW-4875, -76* OFDM Demodulator Quad
SW-4872 for the CW-4878 ASI Descrambler Quad
* in the a CW-4872, -74 and 76 types install also the SW-4872
CAM Analyzer & Programmer software (s. page 4).
39/06
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CW-4871, -72, -73, -74, -75, -76, -78 DEMODULATOR QUAD CW-4871, -72, -73, -74, -75, -76, -78 DEMODULATOR QUAD
The software can be downloaded from
www.cableworld.hu and be used free of charge.
After having installed and run the proper one from the
SW_487x software, set in the CW-Net Connection
panel the IP address of the device you want to address; in this example the 102.
The computer can only address the device if its IP
address is set correctly. In case of correctly set IP
address on clicking the Query button the name and
type of the device will be displayed.
3. HARDWARE AND SOFTWARE SUPPORT
In CableWorld’s system, managing the devices is
based on the CW-Net and it needs beyond the devices a PC only. For controlling the CW-Net, the user
can use his own PC, but if demanded the PC can
also be delivered with the system: the CW-4891 DataBoss 19” rack mounted PC or the CW-4892
DataChief notebook PC.
Data streams of low data rate, e.g. elementary
streams can be processed even with computers of
lower performance.
In order to introduce and spread its unique system,
CableWorld Ltd. supports its user by issuing many
descriptions, guidelines and pieces of software, whose
number will even increase in the future; They can be
freely downloaded from www.cableworld.hu. In the first
phase of the market introduction following materials are
at our users’ disposal:
CW_Net_a.pdf
Summary of establishing the CW-Net, support to
design the first pieces of own software.
CW_Net2a.pdf
Description of the use of CW-Net, block diagram of
the structure of the CableWorld system.
SW-4800 CW-Net Principal
Simple software for establishing the CW-Net, setting
the IP addresses, testing the readiness for operation
and troubleshooting.
SW-4841 ASI to IP & IP to ASI Converter
Control Software
Common managing software for both converter
types, and also for use with other devices. The software permits using the whole IP address range and
provides supports for correcting the errors made at
IP address setting.
SW-4890 Computer Performance Tester
Simple software for testing the set-up and the capabilities of the computer connected to the CW-Net.
SW-4811 TS Analyzer
Transport stream analyzer software for inspecting the
structure and content of the given TS, for developing
and training purposes and for checking the operation
of devices.
Using_CW_Net.pdf
Guidelines for applying the CW-Net, support to make
the first steps, hints for elaborating the applications.
4. PUTTING THE DEVICES IN OPERATION
Connect the device to the specified power voltage
and switch on the mains switch. After a few seconds
the device is ready to operate.
When using the own computer for making the
settings, install SW-4800 CW-Net Principal and the
appropriate from the SW-487x, which are available
for download in the ‘Software’ page at
www.cableworld.hu. The programs install in the
C:\Program Files\CableWorld folder and create an
icon on the desktop. All pieces of software have been
designed for the Windows XP Professional operation
system. The simpler pieces of software can run in
other environment, too but there we have not tested
them.
After having installed the software, set the IP address of the computer to the fixed 10.123.13.201
value, or to any other value within the 10.123.13.x
range (x = 0…255).
For the CW-4891 DataBoss and the CW-4892
DataChief computers these procedures have already
been performed.
4.1 Input signals
The QAM- and OFDM demodulators need input
signals in the 47 … 860 MHz frequency band with a
level of 40 … 85 dBµV. Input signals with too low or
too high level result in the increase of the bit error
rate.
Between the RF IN and the (bridged) RF OUT
connectors the QAM and OFDM demodulator modules are equipped with an amplifier of 3 … 6 dB gain.
When bridging the inputs of multiple modules, be
careful not to overdrive the input amplifiers of the
tuners (when bridging 4 modules, the signal level at
the input of the last tuner will already be by 9 … 18
dB higher).
When bridging the inputs of OFDM demodulators,
sever problems can be caused if the signal coming
from the antenna contains anywhere in the 47 … 860
MHz band analogue TV signals or other signals at a
level by 20 … 30 dB higher than the signal to be received. Such high-level signals can lead to overdrive
even in the amplifier between the RF IN and RF OUT
of the first module. The disturbing products arisen by
intermodulation can appear even in the reception
band, and block the operation of the demodulator. In
such case the antenna signals should be distributed
by directional coupler type distributors.
The QPSK demodulator is equipped between the
RF input and RF output with an amplifier of 0 … 1
dB-gain. Here, bridging will not cause overdriving
unless the level of the input signal is too high.
With QPSK demodulators, by making use of the
bridging possibility, usually no SAT IF distributor is
needed.
From the double ASI outputs of the QPSK-, QAMand OFDM Demodulators one can be used e.g. for
the main stream, the other for connecting a Transport
Stream Analyzer, thus using ASI distributors can be
spared.
4.2. Ethernet converter
Beyond the ASI transport stream output signals of
the 4 demodulator or ASI modules, one of them can
be selected on the GUI of the managing software to
lead it to the Ethernet board and output it in form of
UDP/IP packets.
This output signal is the selected transport stream
implanted in UDP/IP packets. The structure of the
packets is described in the CW_Net_a.pdf file.
The converter implants a continuity counter signal
in the packets, which permits the steady monitoring
of the error-free transmission in the Ethernet network.
Building the network and setting-up the computer are
described in details in the Using CW-Net.pdf file.
Since the computer is not capable of accurate
timing, the Ethernet converter implants in the packets
also the signals of a 25 MHz quartz oscillator. The
details of this PCR-like (Program Clock Reference)
implantation are described in CW_Net_a.pdf, too.
The connection between the device and the computer can be established in the simplest case by
connecting the RJ45 output of the device with the
network card of the computer through a crossover
cable. When connecting multiple devices, they
should be connected through an Ethernet switch, but
in this case with straight cables. The basics of networks building are discussed in the CW-NET_a.pdf,
putting in operation and configuring the computer in
Using_CW_Net_a.pdf.
The detailed instructions for using the devices’
managing software are to be found in the Help
menus of the software and also in pdf format in the
’Software’ page of our web site.
5. TECHNICAL DATA
The technical data of the CableWorld products
are published in their data sheets, which are available at the web site www.cableworld.hu.
Additional technical information:
5.1. All ASI inputs and outputs are insulated from the
frame by transformers, which assure 2000 V separation. This design is very advantageous in applications, where to be prevented is the formation of earth
currents due to transmitting the ASI signal over larger
distances between different rooms or laboratories.
From the point of view of electromagnetic radiations and protection against disturbances, it is advantageous if the outer shielding of the ASI connecting
cable is earthed at a proper point. This point has to
be found individually in each application.
If the user wants to earth the outer shielding of the
coaxial cable just at the device’s output or input, the
product can optionally be delivered with metallic ASI
socket(s) instead of insulated socket(s). In individual
cases the user can easily make the earth connection
with a short jumper.
Troubleshooting for the most frequent problems at
building the CW-Net, configuring the computer, putting the devices into operation and others are given
in the Using_CW_Net_a.pdf file.
We appreciate receiving all remarks, experiences,
measuring results made with our products and we
pay respect to them at our further developments.
Beyond serial products, CableWorld is ready to
deliver products for special demands and implement
individual ideas.
Those customers, who are going to integrate our
products into their systems and undertake writing
own software for operating these products or for solving their individual task, can reckon with our utmost
support. Your questions, ideas and suggestions are
always welcomed at [email protected].
In all four versions of the quad series (QPSK-, QAMand OFDM demodulator quad and ASI Descrambler)
each of the four independent channels is equipped
with an own CI circuitry. Handling the CI interface
and configuring the CAM modules is made with the
SW-4872 CAM Analyzer and Programmer software,
separately from the settings of the high frequency
demodulator parameters.
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