CableWorld CW-4142 User manual

CW-4000
DIGITAL PROFESSIONAL CABLE TV HEADEND
USER'S MANUAL
08/05
CW-4142
QPSK DEMODULATOR

CW-4142 QPSK DEMODULATOR
Dear User!
The CW-4142 QPSK DEMODULATOR is a new
member of CableWorld’s digital satellite receiver
family. This instrument provides two more essential
features as compared to the earlier ones:
• it can accommodate a Conditional Access Module
(CAM), thus provide reception of scrambled
programs,
• it is equipped with Asynchron Serial Interface
(ASI) which permits the transport stream to be
accessed directly.
Prior to take into operation the unit please read
through this User’s Guide carefully.
1. Mechanical construction
The CW-4142 QPSK DEMODULATOR is accom-
modated in a standard 1 unit high 19" rack frame.
The unit is delivered along with the following
accessories:
1. Fuse T0.4 A (slow) 1 ea.
2. Power cord 1 ea.
When mounted in rack cabinet, place the CW-4142
QPSK DEMODULATOR above the relevant TV
MODULATOR. These both units together form a
channel processing assembly. The channel
processing assemblies have to be separated from
each other with CW-3004 VENTED COVER
PLATEs, to provide sufficient ventilation.
2. Electrical construction
The CW-4142 QPSK DEMODULATOR equipped
with proper CA module and valid SmartCard
(subscriber card) demodulates the input QPSK
modulated satellite IF signal (920-2150 MHz) and
delivers the complete transport stream, which
includes those channels having been processed by
the Conditional Access Module in descrambled
form.
Beyond this, one selected program of the TS (FTA
or descrambled) will be MPEG-2 decoded and after
digital/analogue conversion is delivered as base
band video and sound signal.
The input and output connectors are arranged in
the unit's rear panel:
2 × "F" type sockets QPSK SAT IF input and
loop-through output
1 × BNC socket video output
1 × BNC socket ASI output
2 × RCA sockets stereo sound channel outputs
2 × RJ12 sockets CW-Bus
All connections have to be made with high quality,
low attenuation cables. Such cables and cable sets
are available in CableWorld’s product range.
The CW-4142 QPSK DEMODULATOR is com-
posed of following subunits:
- QPSK demodulator and error correction circuitry,
- Common Interface circuitry with standard PCMCIA
socket accessible form the front panel,
- MPEG-2 video and audio decoder and
- microprocessor-based control unit.
The instrument incorporates an own switched mode
power supply. This power supply is accommodated in
the right side of the unit, under a shielding cover and
it delivers all necessary supply voltages.
The mains switch and fuse are located on the unit's
rear panel. The fuse is accessible after unscrewing
the fuse holder.
The switched-on state of the demodulator is
indicated by a yellow LED on the front panel.
The required reception parameters can be set with 8
front panel buttons. The operation modes are
indicated with LEDs and the actual parameter values
in a 2×20 character LCD display, on the front panel.
The LCD display is equipped with own back lighting.
Without pushing any of the buttons for more than 30
minutes, the back lighting turns down automatically,
and turns on again on pushing any of the buttons or
inserting or removing the CAM or the SmartCard.
3. General information
After switching on the demodulator,
INITIALIZING...
appears in the display, followed by
SELECT MENU.
Use the MENU button to choose the Normal, or
the Extended menu.
As basic setting, the control unit calls the normal
menu, which includes only those menu items
necessary to set the reception parameters. The
extended menu delivers additional information
about several internal parameters and permits to
set some rarely used functions. The extended
menu can be used to locate errors, too.
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CW-4142 QPSK DEMODULATOR
3.1 Using the push buttons
Sand T
The requested parameter can be selected with the
Sand Tbuttons. With these buttons you cycle
through the available parameters (menu items).
Wand X, and SHIFT
The value of the selected parameter can be
increased or decreased with the Wand Xbuttons.
If the SHIFT button is pressed simultaneously, the
rate of the change is higher.
MENU
This button calls the SELECT MENU item, and its
second push changes between Extended and
Normal menu.
STORE
The changes made to the operating parameters
can be stored with pushing this button. On pushing
the button, the demodulator writes all parameter
values into its non-volatile memory. Therefore the
STORE button needs to be pushed once only, after
having set all parameters. The storing procedure
takes approximately 1 second. During this time the
display shows SAVING....
RECALL
The data stored last can be recalled with the
RECALL button. On pushing this button, all
parameters will be set back to their stored values.
The ←and →characters appearing in the right
bottom corner of the display show whether the
actual parameter is adjustable and at the same
time they also indicate the relevant button for
change it. If none of the ←and →characters
appears, the value of the selected parameter
cannot be changed.
3.2 Meaning of the front panel LEDs
DEMOD LOCKED
If this LED lights, the demodulator is receiving the
modulated QPSK carrier at proper level and it was
able to lock to the carrier. The demodulator can
only lock if the receiving frequency and the symbol
rate are set to the proper values.
LNB SHORT
This LED flashes if an error occurred in powering
the LNB. After the short circuit has been removed,
it goes out automatically.
SIGNAL LOW
This LED lights if there is no input signal or the
level of the input signal is not sufficient.
SYSTEM ERROR
This LED flashes if an error occurred in the internal
microprocessor control of the unit. After termination
of the error it goes out automatically.
4. Adjustable and query only
parameters in the normal menu
SELECT MENU
Normal usual setting
Extended the whole set of parameters
available
After pushing the MENU button, the SELECT
MENU item appears. On a further push the
Normal menu will be changed to the
Extended menu or reversed.
After switching on the demodulator, the log in is the
Normal menu. Switching over to the other menu
can be made with the Wor Xbutton, too.
LNB LOCAL OSC.FREQ.
Available Lo values:
9.75 GHz
10.00 GHz
10.60 GHz
In this menu item the demodulator will be informed
about the local oscillator frequency (Lo) of the LNB
used with the demodulator. When using universal
LNB make sure that the transponder frequency is
within the receiving frequency range determined by
the setting of the LNB local oscillator frequency.
When setting 10.60 GHz, the demodulator
automatically outputs a 22 kHz switching signal to
switch over the oscillator in universal LNBs.
RECEIVING FREQUENCY
Receiving frequency ranges:
with Lo set to 9.75 GHz: 10700 ... 11900 MHz
with Lo set to 10.00 GHz: 10950 ... 12150 MHz
with Lo set to 10.60 GHz: 11550 ... 12750 MHz
("Lo" is the frequency of the LNB's local oscillator)
To receive a transponder, set the receiving frequency
to the transmitting frequency of the transponder.
Once the value for Lo has been set in the LNB
LOCAL OSC.FREQ. item, it determines the
receiving frequency range. (When attempting to set
the receiving frequency beyond the upper limit or
below the lower limit of the frequency range, the
change of the frequency will stop at the limit despite
of pushing the frequency increase or frequency
decrease button respectively.)
CARRIER FREQ. DEV.
This parameter gives the difference between the
actual and the nominal frequency of the LNB's local
oscillator. If the demodulator is locked (the DEMOD
LOCKED LED is lighting), this frequency difference
can be minimized by pushing the Wor Xbutton. On
this, the (nominal) frequency value set at the
RECEIVING FREQUENCY menu item will be
corrected for optimal reception.
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CW-4142 QPSK DEMODULATOR
After each modification of the receiving frequency
(e.g. tuning to an other transponder) it is
recommended to minimize this frequency
difference, which means adjusting the demodulator
to the LNB. Later on, it is sufficient to check the
frequency difference from time to time and keep it
below 1 MHz.
LNB POWER & POLAR.
Available values:
Off LNB powering switched off
Vertical (14 V) vertical polarization
Horizontal (18 V) horizontal polarization
The LNB powering is equipped with automatic
short circuit protection. In case of short circuit the
LNB powering will be switched off for 4.5 seconds
then the demodulator attempts to switch on
powering for 0.5 seconds. This procedure is
followed until the short circuit is removed. The
short circuit is signalized by a flashing LED on the
front panel.
SYMBOL RATE
Adjustable range: 2... 45 Ms/s
To receive a transponder it is indispensable to set
the symbol rate to the right value.
(E.g. the Astra satellites typically use 27.5 Ms/s.)
Display of the program name, e.g.
CNN Int.
TV PROGRAM
This menu item shows the name and kind (TV,
radio, data) of the program stored last.
In this menu item, the SEARCH FOR
CHANNELS menu is entered by pushing the Wor
Xbutton. The search can be started with the SHIFT
button. For a search the reception parameters
(frequency, polarization and symbol rate) must have
already been set. According to the number of
programs available, the search procedure can even
last 30 sec. During this time SEARCHING FOR
CHANNELS... is displayed, and the change in
the number of dots is indicating the search being in
progress.
After an unsuccessful search (e.g. without input
signal) the unit returns to the name (and PID
values) of the program stored last.
After a successful search the display automatically
shows the name and kind of the program found
first. The Wand Xbuttons permit to step through
the programs found, which unless scrambled and
the CA modul in the PCMCIA socket with the
SmartCard cannot descramble them, appear on
the screen. For radio programs, colour bars can be
displayed on the screen, if the menu item
COLOUR BAR is switched to On. The data of the
selected program can be stored with the STORE
button. After store, new programs can only be
reached through a new search (with pushing Wor
X, then the SHIFT button). If the unit cannot
interpret the name of the program, UNKNOWN will
be displayed along with a serial number, which
indicates the program’s position in the packet, and
only serves the distinction for the case of more
than one UNKNOWN program.
Most CA modules can descramble one program only
at the same time. In such case, on pushing the
STORE button, the module goes to the position of
descrambling the program selected to the display.
However CA modules of later design are able to
descramble more than one program at the same time.
The CW-4142 QPSK DEMODULATOR supports this
facility. In this case, after the search procedure, the
programs to be descrambled simultaneously can be
selected with the SHIFT button.
Here, the selected program is denoted with a <
mark in the second row of the display after the TV
PROGRAM or RADIO PROGRAM information.
The selection can be cancelled by pushing the
SHIFT button once again. For simultaneous
descrambling up to 16 elementary streams can be
selected, after which on pushing the SHIFT button
no more selection occurs and the <mark does not
appear again.
The 16 elementary streams can cover e.g. 4
services including one video, two audio and one
teletext stream each.
Note: Since the unit is equipped with one MPEG-2
decoder, it can deliver the analogue base band video
and sound of one digital service only. This is always
the service selected last!
However, in the transport stream at the ASI output
all digital programs, among them the descrambled
ones are available, and can be lead to
remultiplexers and/or further MPEG-2 decoders.
If after having made selection for descrambling, the
STORE button is pushed with a not selected
program in the display, the unit stores the selected
programs and goes back the program selected last.
If the module is able to descramble one service only,
the QPSK DEMODULATOR sends to the module
the data of all services selected to descrambling, and
always the service selected last will be descrambled.
The sequence of the data of services sent to the
module is identical with the sequence of selecting
the services.
With modules capable of multiprogram descrambling
any of the selected services can be appointed to be
MPEG2 decoded and displayed on a video monitor.
With modules capable to descramble one service
only, take care of the service sent to the MPEG2
decoder, because on receiving a non-descrambled
service the MPEG2 decoder outputs neither picture
nor sound.
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CW-4142 QPSK DEMODULATOR
Therefore with such modules, when pushing STORE,
one service should be selected only, or the display
should read the name of the service, which is
descrambled.
SELECT AUDIO
This menu item permits selecting the desired sound
channel when receiving programs with more than
one audio channel (e.g. multilingual transmissions).
The availability of more than one sound channel is
indicated by the ←→mark.
The desired sound channel is then selected with W
and X, and can be stored with the STORE button.
After store, the PID of the selected sound channel
is displayed and there is no more possibility to
select, what is indicated by the disappearance of
the ←→mark. AUDIO LEVEL
Adjustable range: 0... 13
With the AUDIO LEVEL parameter the
amplitude of the output audio signal (L, R) can be
adjusted. The audio amplitude is increasing with the
scale numbers. At the value of 0 the audio signal is
switched off. Factory setting is 7, which
corresponds to a medium volume.
DECRYPTED PROGRAMS
In this menu item the list of the programs having
been selected to descrambling is shown. The W
and Xbuttons permit stepping forward and
backward in the list. The ←and →characters in the
display show the direction in which further list
elements can be found.
5. Ajustable and query only
parameters in the extended menu
In the extended menu some further menu items
appear among the items of the normal menu:
Factory settings:
In this menu item, by pushing the RECALL button,
the factory settings can be retrieved, which are
following: ASTRA 19.2°, 11778 MHz, vertical
polarization, 27.5 Ms/s, CNN International.
Satellite parameters:
SNR: 5 ... 20 dB
(Signal to noise ratio)
VCR: 1/2,2/3,3/4,5/6,7/8
(Internal error correction code ratio)
CORR.RS.ERR: 0 ... 65535
(Number of the correctable RS errors)
The above parameters provide the user with
following information:
− With no input satellite signal the SNR value is
less than 5dB. For a reliable reception
approximately 10 dB should be assured. (Use
an antenna of adequate size!)
− The VCR parameter shows the value peculiar to
the internal (Viterbi) error correction coding of the
transport stream. The unit automatically searches
this parameter; it cannot be set manually.
− The CORR.RS.ERR parameter shows the
total number of the Reed-Solomon errors in the
packets having occurred since the appearance
of the DEMOD LOCKED state. The correctable
errors do not cause visible deterioration of the
picture. This parameter shows the reception
quality in an indirect way. In case of reliable
reception (with proper input level even at
adverse weather conditions) the correctable RS
errors are stable at zero.
The displayed value can be reset with pushing
the Wor Xbutton.
VIDEO PID NUMBER
This menu item indicates the video packet identifier
of the selected program. This PID enables the
demodulator to extract the concerning video signal
packets from the transport stream.
The Video PID is searched and set automatically
and cannot be set manually.
PCR PID NUMBER
The PCR (Program Cock Reference) PID indicates
the clock reference of the received program. These
packets serve for the synchronisation of the
demodulator's clock generator. The value of the PCR
PID often is identical with that of the Video PID.
The PCR PID is searched and set automatically
and cannot be set manually.
TELETEXT PID NUMBER
In this menu item the identifier of the teletext
packets belonging to the received program is
indicated.
The Teletext PID is searched and set automatically
and cannot be set manually.
AUDIO PID NUMBER
In this menu item the PID of the sound track of the
received TV program or of an independent radio
program is displayed. This PID enables the
demodulator to extract the concerning sound
packets.
The Audio PID is searched and set automatically
and cannot be set manually.
AUDIO MODE
This menu item indicates the mode of the received
audio channel: mono, stereo, dual etc., and cannot
be set.
Audio parameters:
AU.SMPL.FR.: 0 ... 48000 Hz
(Audio sampling frequency)
AU.BIT RATE: 0 ... 448 Kb/s
(Audio bit rate).
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CW-4142 QPSK DEMODULATOR
All the above parameters give information about
the internal parameters of the demodulator and the
received program. These parameters are not
adjustable. COLOUR BAR
Off
On
With the colour bars switched to On, when
receiving radio programs the demodulator delivers
standard vertical colour bars with 75 % saturation
for measurement purposes.
Version numbers:
FWS (Firmware System)
FWA (Firmware Audio)
DEV (MPEG Decoder Chip Version)
SW (Software Version)
The above parameters serve for information
purposes only.
Error codes:
ERROR CODE: 0 ... 255 XXXXXXXX
The error codes indicate the internal error states of
the receiver, for use at repair. The error code can
be reset with the Wor Xbutton. On resetting, the
SYSTEM ERROR LED ceases flashing. Should
the demodulator continue defective operation,
restart it with switching off and on. If an error
occurs during initialization, the control circuitry
inhibits the operation.
6. Service menu
The Service menu can be selected in the
SELECT MENU item by pushing the Xbutton
twice. Here, the bus address of the unit can be set,
that is important when establishing remote control
from the PC through bus.
Further the type number, serial number and
software version of the unit can be checked.
7. Important information
The CW-4142 QPSK DEMODULATOR
continuously monitors in the input stream the
Program Map Table (PMT), which describes the
program content of the stream. In the case of any
change in the stream (e.g. PID change), the unit
performs the corresponding modifications in the
settings of the CA module and the MPEG-2
decoder.
This permits the demodulator to automatically
follow possible changes in the transmitter side
(e.g. regional switch-overs etc.)
The operating software of the CW-4142 QPSK
DEMODULATOR recognizes and supports the CA
modules belonging to the most frequently used
scrambling systems (CryptoWorks, Viaccess,
Irdeto, Nagravision etc.). In case of any problem
with recognizing some module type or module
make please contact our customer service. If the
SmartCard is removed from the CA module, the
module sends a type depending error message,,
which overrides the display for 5-6 seconds then
the original display returns.
This sequence repeats in about every 5 seconds.
After the card is inserted again, the error message
leaves off. The error message can also include
messages for set top boxes with IR remote control
e.g. SMART CARD ERROR, PRESS OK.
These messages should be disregarded.
If after having set it, the CA module does not
descramble for some reason, remove the card
from the module and insert it again.
The recommended sequence for setting the CW-
4142 QPSK DEMODULATOR:
1. Set the reception parameters: LNB Lo
frequency, reception frequency, LNB powering
and polarization, symbol rate.
If everything was made correctly, the DEMOD
LOCKED LED lights.
2. Minimize the frequency error in the
CARRIER FREQ. ERROR menu item.
3. Go to the program name display menu item
and start search as described there. As the
unit has found the first program of the packet,
insert the concerning CA module with the
card in it. In a few seconds the descrambled
picture appears on the screen.
4. Now step the programs round, check them
on the screen, and select with the SHIFT
button those you want to have descrambled.
Mind the described limit of descrambled
streams. When only one program has to be
descrambled selecting is not needed.
Selecting non-scrambled (FTA) programs is
not permitted by the software.
Save the settings with pushing the STORE
button.
Further, prior to starting a new channel search or
prior to changing transponder, always remove the
module from the unit first.
Dear User!
Setting the parameters of the CW-4142 QPSK
DEMODULATOR needs care and accuracy. In case
of incorrect setting the reception of the requested
program will fail. Should you face any problem after
reading this guide please contact our customer
service.
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CW-4142 QPSK DEMODULATOR
Technical data
TV System DVB-S / MPEG2
Input data
Input signal 950 to 2150 MHz
Input level -65 to -25 dBm
IF bandwidth 36 MHz
Input impedance 75 Ω
Transmission characteristics
Modulation type QPSK SCPC / MCPC
Symbol rate 3 to 30 Msps
FEC DVB compatible
LNB powering 14 / 18 V
(short circuit protected)
LNB oscillator switching 0 / 22 kHz
Video decoding MPEG2 MP@ML
Video rate 1.5 to 15 Mbps
Aspect ratio 4 : 3 and 16 : 9
Maximum resolution 720 × 576
Audio system MPEG1
MUSICAM (layer1 / 2)
Sampling frequencies 32, 44.1, 48 kHz
Teletext signals inserted into the vertical
blanking intervals
according to standard
ITU-R653-1 System B
Common Interface acc. to EN 502221/1997
Output data
Video output
Colour system PAL / SECAM
Output impedance 75 Ω
Output amplitude 1 Vpp
Sound output
Nominal output level approx. 0 dBm
scale number ~10,
depending on the
transmission
Adjustable range scale number 1 to 13
approx. -24...+10 dBm
0 (Muting)
ASI output ISO/IEC 13818-1
TM 1449 Rev.1
Output data rate 270 MBaud
Output level typ. 800 mVpp
General data
Mass approx. 3.5 kg
Physical dimensions 19” × 1HU
Width 483.0 mm
Height 43.6 mm
Depth 473.0 mm
Service period continuous
Power requirement 230 V +10 ... -15 %
50 / 60 Hz
Power consumption max. 50 VA
Operational temperature range
- to fulfil the specifications +10 ... +35oC
- to maintain operation 0 ... +40oC
- relative humidity 80 %
Storage temperature range - 25 ... +45oC
- relative humidity 95 %
non condensing
7
H-1519 Budapest, Pf. 418
Hungary
Tel.: ++36 1 204 7815
Fax: ++36 1 204 7839
E-mail: [email protected]
Internet: www.cableworld.hu
Ltd.
ASI
Interface
ASI out
QPSK
Demodulator and
FEC Decoder
Demultiplexer &
MPEG-2 Decoder
Common
Interface
ADC
AGC
Sat
Tuner
LPF
LPF
RF in
I`
Clock
Data
Clock
Control
Bus
CW-4142 QPSK DEMODULATOR
Q`
I
Q
Audio
DAC
PAL Encoder
& TXT
Inserter
Data
Data Clock
LPF LPF
L/R out CVBS out
DRAM System clock
Host
Processor
Display &
Control Unit
Clock Data
Data
Clock
PCMCIA
Connector
DataClock