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.