Alcad DM-102 User manual

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Technote10: Setting up DM-102 COFDM Modulators with PS-011
DM-102 is a fully agile Digital Modulator which is designed to convert 2 AV
signals into a digital modulated channel.
IMPORTANT: Layout of the modules must be as shown above. Power Supply (FA-312) must
be located on the far left hand side and launch amplifier (PA-720) must be the next module in
the chain. Please look at the layout above. A limit of 6 DM-102 modules can be powered by
one FA-312. If FA-310 is being used only 3 modules is the limit due to power consumption.
AIM PROGRAMMER TO IR SENSOR LOCATED ON EACH DIGITAL
MODULATOR WHEN PROGRAMMING
Programming of Modules
Ensure the following prior to programming:
•It is necessary to connect all the modules to the support frame SP-226 (code 9120130)
for the system to function.
•It is also recommended that you make the earth connection to the building using a cable
with a section of at least 4 mm.
•Ensure that you have the Alcad programmer PS-011 with firmware version 1.11 or
later.
•Power supply/Control cable must be plugged into each module. DO NOT ADD OR
REMOVE modules without disconnecting mains supply power from wall outlet. Always
disconnect the equipment, and then reconnect it to the mains supply. Failure to do so
can cause equipment to fail.
Launch Amplifier
Power Supply
IR Sensors

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OPERATION OF PS-011 PROGRAMMER

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1.0 Programming of the Modulator
To program the Digital Modulator, place the programming switch in the ON (upward) position
which can be seen from picture below. When you turn the switch in the “ON” position the
programming indicator will light up. While the programming indicator remains lit, the modulator
is ready to receive data from the PS programmer. When the modulator has been programmed,
programming mode should be deactivated by placing the switch in the “OFF” position. The
programming indicator light will go out.
To start programming the DM-102 module you desire to programme please slide the
programming indicator switch to the ON position.
Press the On/Off button on the PS-011 programmer to turn on programmer.
You should then see the window below which gives you the following options:
Ensure that “Select Series” is highlighted then press the button which will take you to the
window on the next page. Using the arrow down scroll down to “DM A/V to DVB-T
modulator”

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Once you have scrolled the selection bar to the modulator press the button to take you to
another window which can be seen below
Press the button to take you to “Output” configuration screen which can be viewed below

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The following output settings options are as follows:
Standard has two options:
- DVB-T is an abbreviation for Digital Video Broadcasting-Terrestrial. Select this option for
Television reticulation.
- DVB-H is an abbreviation for Digital Video Broadcast-Handheld. Select this option for
Mobile Handsets.
Once you have selected the “Standard” option press transmit button on the programmer
to send the change through to module.
Program by has two options:
- Frequency meaning that the output of the modulator is done so by the frequency
entered e.g. 655.50.
- Channel meaning that the output of the modulator is done so by channel number.
You should always select to Program by “FREQUENCY” as this stops confusion of any changes
made to country channel plans.
Once you have selected the Frequency option press the transmit button to send the changes
through to the modulator. The next two options ‘Channel table’ and ‘Channel’ will be locked and not
applicable if the setting ‘Program by Frequency’ has been selected on the last option as per ALCAD
recommendation.
Frequency is the selection box where you need to enter the output digital RF frequency you desire the
modulator to output the V/A feeds to. If you are unsure of the frequencies please note the Australian
digital Channel/ Frequency plan below.

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DIGITAL FREQUENCIES FOR AUSTRALIA ARE HIGHLIGHTED IN YELLOW
Press transmit button on the programmer to send the change through to module.

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Attenuation is the dropdown box that allows you to adjust the power level output of the
modulator.
Press transmit button on the programmer to send the change through to module.
Offset is the dropdown box that gives you the option to add or subtract either 0.166 or
0.125MHz of the output digital RF frequency. Look at table to give you the decimal
conversion.
Fraction
Offset
Decimal
Offsets
+ 1 / 6
+0.166
- 1 /6
-0.166
+ 1 / 8
+0.125
-1 / 8
- 0.125
Bandwidth in Australia must ‘ALWAYS’ be set to 7 MHz .
Press transmit button on the programmer to send the change through to module.
Mode can be set to either 2K or 8K. DVB-T offers a choice of two options for the number of
carriers, each with the same fundamental data capacity. In "2K" mode, 1705 carriers are used
to carry symbols with a useful duration of 224m s, whereas in "8K" mode there are 6817
carriers with a useful symbol duration of 896m s. The reason for having two modes is to allow
a trade-off to be made between receiver complexity and the ability to withstand long echoes.
Press transmit button on the programmer to send the change through to module.
Modulation has 3 modulation options QPSK, 16QAM, 64QAM. There is a balance between the
amount rate at which data can be transmitted and the signal to noise ratio that can be
tolerated. The lower order modulation formats like QPSK do not transmit data as fast as the
higher modulation formats such as 64QAM, but they can be received when signal strengths
are lower.
Press transmit button on the programmer to send the change through to module.

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FEC (forward error correction) has 5 option rates. All broadcast systems transmitting data will
suffer errors. In order to correct these errors various forms of error correction are used. The
rate at which this is done affects the rate at which the data can be transmitted. The higher the
level of error correction that is applied, the greater the level of supporting error correction data
that is needed in order to be transmitted.
In turn this reduces the data rate of the transmission. Accordingly it is necessary to match the
forward error correction level to the requirements of the broadcast network. The error
correction uses Convolutional Coding and Reed Solomon with rates of 1/2, 2/3, 3/4, 5/6, and
7/8 dependent upon the requirements.
Press transmit button on the programmer to send the change through to module.
Guard Interval has 4 different interval rates 1/32, 1/16, 1/8 and 1/4. Guard Intervals are used to
ensure that individual transmissions do not interfere with each other. In COFDM systems the
beginning of each symbol is preceded by a guard interval. As long as the echoes fall within this
interval they will not affect the receiver’s ability to safely decode the actual data. We generally
recommend using 1/16.
Press transmit button on the programmer to send the change through to module.
Cell ID is a unique number that is used to identify the transmission from base station tower.
Press transmit button on the programmer to send the change through to module.
We now come to the services section of the programmer. Please look below at the screenshot
below.

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Please note the following screenshot and settings:
ACTIVE- To enable the input to be active the option must be set to “ON”. If you do not want
the input to be seen or is not going to be used set to “OFF”.
Press transmit button on the programmer to send the change through to module.
SERVICE ID – This number needs to be unique and never repeated with any other modulator
on the same network. Thus on the next modulator service ID must be 3 and 4 and so on
Press transmit button on the programmer to send the change through to module.
SERVICE NAME – Enter the Service Name which will be displayed on the Television Screen when the
user goes to this channel on the TV set. This is like GEM, ONE, GO which the general broadcasters
use.
Press transmit button on the programmer to send the change through to module.
AV Input 2
AV Input 1

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ADVANCED – The ADVANCED menu option needs to be set to enable PID and bitrate
configurations for Video and Audio.
Service Provider - This name entered needs to be used on all modulators that are on this
same network. Therefore if you have 4 modulators on the system you will need to enter
whatever name of the network you use on all 4 modulators. In this case we have used Mantra
Network for this example but you can use Quest or Crown. It is best to use the name of the
building that the equipment is being installed , so that serviceman can identify that this channel
being broadcast is from the building and not Free-to – air services.
Press transmit button on the programmer to send the change through to module.
Video PID – This number needs to be unique and should never be repeated on any other
modulator within the same network. A good value to start at is 105.
When you set the second input the Video PID should be 110. Always allow 5 values from your
last PID. On the second modulator the Video PIDS should be 115 and 120 etc...
Press transmit button on the programmer to send the change through to module.
Video Bit Rate- The video bit rate is a desired setting from the user we generally say that 7000
Kbps to 8000Kbps gives the best results and allows enough room for fluctuations of bandwidth
within the modulator.
Press transmit button on the programmer to send the change through to module.
Name of the network
you want the signal to
be broadcast to

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Audio PID- This value should ALWAYS be one value increment of the Video PID that was
entered. Thus if you have set 105 for the Video PID then you should set 106 for the Audio PID.
Press transmit button on the programmer to send the change through to module.
Audio bit rate – The audio bit rate refers to the number of bits used per unit of playback time to
represent a continuous medium such as audio. There are 10 options for you to choose from.
We generally recommend using 192 or 256 Kbps. The lower the value the poorer the audio
quality will be. The value is also proportional to the bandwidth being used from the modulator
which is displayed below this setting.
Press transmit button on the programmer to send the change through to module.
The Service bandwidth is indication information and should never exceed 45%. If the Service
BW is higher than 45% you can lower the rate by dropping he Video Bit rate or the Audio bit
rate.
Once you have set all the parameters to your liking press the button to take you back
into the previous parameters screen that can be seen below.
TS ID- This number needs to be unique to the modulator system. We recommend that this
number coincides with the position of where it sits on base plate. Transport Stream ID number
must not be repeated again on another modulator on the same network.
Press transmit button on the programmer to send the change through to module.
TS ID number needs to
be unique with each
modulator
Cannot be
changed

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Press the down arrow to take you to the next window of parameters that need to be set.
Please set these settings to your liking.
Press transmit button on the programmer to send the change through to module on each
parameter that has been changed.
You now need to save the settings. To do this you need to press the “MENU” button on the
programmer.
Pressing the Menu button will bring up “Configuration File” window. This window enables you
to either save or load a previous configuration.
In this case you need to save the configuration. Highlight the save configuration and press the
OK button and you will be asked to give the file a name, so enter the name of the file.
Press Menu button

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Once you have entered name you desire press okay and enter module number 1. This name
must also be unique. Each modulator configuration settings file should be called a different
name e.g. Quest 1. Press OK and you are given confirmation of your saving of the
configuration file as can be seen below.
Press OK once again and then press ESC button 3 times to take you back to the Main Menu
window. You then need to highlight “NIT Table” and press OK.
You will then be taken to a screen where you need to select the “configuration file” of the
modulator you wish to set the LCN (Logical Channel Numbers) to. The file will be xxx.cfi .
Highlight the file and then press OK button to take you to the “NIT table” window which can be
seen below.
Enter the Network name as the Service provider that you entered prior the name of the
Building the network was installed “Mantra Network”.

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Press the OK button and you will be taken to the Channel Numbering (LCN) window. Look at
screenshot below which shows the program names of the modulator you are setting the LCN
for.
Where the blue block is highlighted enter the desired LCN number with the Program name and
the press down arrow so that the blue highlight block is on the next LCN. Once you have
entered the desired LCN channel numbers press the OK button.
DO NOT USE ANY LCN NUMBERS THAT ARE BEING
USED BY FREE-TO-AIR BROADCASTERS SUCH AS
90,99,10,24 etc......
LCN Number is the
channel that will
appear on the TV set
Service Name of AV
Input 2
Service Name of AV
Input 1

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For a brief period a window will show calculating NIT, and move to the screenshot that can be
seen below.
Press the button to send the NIT to the modulator. Successful completion of the NIT
transmission is confirmed by the programmer with the green tick on the window.
You have now successfully programmed the DM-102 modulator. If you are still experiencing
problems with programming, please contact ALCAD technical support on 03 9720 5329.