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====== RX1 Modulated Input ======
<color darkorange>Nov 2023</color>

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===== Introduction =====
It has been quite some number of years since I dealt with Modulators and Receivers, so I did struggle a little with this recently, these are some notes of the values I used, just to get a Mod/Demod setup going.
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==== Hardware Connections ====
See below for the connection method between the AVP and the RX1.
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{{ :avp_rx1.jpg?nolink&700 |}}
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The Monitor F-Type output of the AVP is connected directly to the RF input of the RX1 (RX4 is on the left). There is no up-convertor or attenuator in use.
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==== AVP Output Parameters ====
Below is the output settings I used on the AVP Modulator.
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{{ :avp_output_parameters.jpg?nolink&800 |}}
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=== Output Parameters ===
<file>
RF Carrier ID State            On (don't confuse this with Modulation on)
Output Select                  L-Band
Output State                   On Reduced Power (we don't want to overload the RX1 input)
Output Power-up State          (Last State)

</file>
=== L-Band Output ===
<file>
Frequency Input Mode           L-Band Frequency
L-Band Frequency               1070 MHz
Reduced L-Band Line-up Power   -5
Nominal L-Band Power           -10
L-Band Spectrum Sense          Inverted
L-Band Tilt                    0
L-Band Up-converter Frequency  2500 MHz
Upconverter Power              Off
Upconverter Reference          Of
</file>
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The settings on this page determine what frequency you are transmitting on.
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==== AVP Modulation Parameters ====
Below is the Modulation settings I used on the AVP Modulator.
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{{ :avp_modulation_parameters.jpg?nolink&800 |}}
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<file>
Modulation Standard            DVB-S2
Modulation State               On
Modulation                     8PSK
FEC Rate                       3/4
Frame Size                     Normal
Pilots                         Off
NCR Stamping PID               8191
Symbol Mapping Mode            Mean Power
PL Scrambling Sequence Number  0
Symbol Rate                    31.25
Roll-off Factor                20%
Bandwidth                      37.5 Mhz (Auto Calculated from the above modulation settings)
</file>
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The settings on this page determine the amount of bandwidth that is available, in this case it is 37.5 Mhz.
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==== RX1 Input Settings ====
See Below for the RX1 Demodulation settings.
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{{ :rx1_modulator_input.jpg?nolink&700 |}}
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<file>
Input Type            Satellite
Source                RF4 (in this example)

LNB
LNB Frequency         5150
LNB Voltage           (voltage off) this is because we don't actually have an LNB in our system.
22kHz                 not selected, same reason as above.


Tuner
Frequency             4080 (5150-4080=1070. 1070 is the L-Band Freq we set in the AVP)
Symbol Rate           31.25
Search Range          10000
C/N margin alarm      2.0

Everything else off.
</file>
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==== RX1 Input Status ====
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On the same page as you entered the RX1 demodulation settings, once you have started the receiver service, you should see the following input status.
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{{ :rx1_input_status.jpg?nolink&600 |}}
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