SRS-01 SRS-02 Page 1 of 31 SRS-01 SRS-02 Encoder 4MPX-ASI Decoder ASI-4MPX User Manual
SRS-01 SRS-02
Page 1 of 31
SRS-01
SRS-02
Encoder 4MPX-ASI
Decoder ASI-4MPX
User Manual
SRS-01 SRS-02
Page 2 of 31 Version 2.0
0. Summary
1. GENERAL DESCRIPTION ................................................................................................................... 3
2. TECHNICAL SPECIFICATIONS......................................................................................................... 4
2.1. SRS-01. ................................................................................................................................................... 4 2.2. SRS-02. ................................................................................................................................................... 4 2.3. LOOP ENCODER-DECODER. ................................................................................................................... 5
3. INSTALLATION. .................................................................................................................................... 6
4. THEORY OF OPERATIONS................................................................................................................. 7
4.1. BLOCK DIAGRAM. .................................................................................................................................. 7 4.1.1. SRS-01. ................................................................................................................................................ 8 4.1.2. SRS-0.2 .............................................................................................................................................. 12 4.2. USER INTERFACE (KEYPAD + DISPLAY). ............................................................................................. 15 4.2.1. SRS-01. .............................................................................................................................................. 17 4.2.2. SRS-02. .............................................................................................................................................. 20
5. EXTERNAL DESCRIPTION............................................................................................................... 24
5.1. SRS-01. ................................................................................................................................................. 24 5.1.1. FRONT PANEL. .................................................................................................................................... 24 5.1.2. REAR PANEL. ...................................................................................................................................... 26 5.2. SRS-02. ................................................................................................................................................. 28 5.2.1. FRONT PANEL. .................................................................................................................................... 28 5.2.2. REAR PANEL ....................................................................................................................................... 30
SRS-01 SRS-02
Page 3 of 31
1. General Description
The SRS systems (Software Radio System) are the last series of Elber products in the
analogue audio (mono or MPX stereo) application field.
The SRS-01 and the corresponding receiving equipment SRS-02 were realized for the
transport of the analogue signal over digital microwave link with ASI interface, utilizing for
example the Elber modem DDM310.
In detail, in the SRS-01 up to 4 MPX signal with level from 0 to +9 dBm (on an impedance
of 600 Ohm) can be accepted as input; a level regulation circuit, programmable by user
interface (3 dB step) let to have always the same level before the A/D conversion.
Digitalization of signals is performed with a 13 bit resolution and the samples are
encapsulated in a DVB-ASI standard frame with a bit-rate of 9.2 Mbit/s.
The ASI output can be connected directly to the input of an Elber digital link or multiplexed
by an ASI concentrator like the RK210/RMX4 together with other heterogeneous streams
(ex.: TV encoder output, MUX DVB-T output or other interfaces).
The digital link should perform a transparent transport of the information, that’s to say no
data should be modified passing from the transmitting site to the receiving site.
The ASI stream received should be decoded by the SRS-02, which recovers the MPX
signals samples from the ASI stream and drives them towards 4 D/A converters.
The following amplifying stages permit to have a 6 dBm signal (on 600 Ohm impedance) at
the output, with the possibility of a digital level regulation (max ±6dB).
Functions management and device monitoring can be done by user interface (keypad and
LCD installed on the front panel). 4 contacts without voltage on the rear panel are also
available; every contact is referred to the respective MPX channel (1 to 4).
Optionally, it is possible to generate 4 carriers, modulated by the MPX carried in the ASI
stream, in a 0-18MHz baseband; these carriers can be up-converted in FM band by an
external up converter in order to utilize them as exciter of a FM transmitter.
Another option, complementary to the previous, is a receiver of a base band (0-18 MHz)
which can demodulate up to 4 carriers and transport the MPX samples over the ASI
stream.
SRS-01 SRS-02
Page 4 of 31 Version 2.0
2. Technical Specifications.
2.1. SRS-01.
Bandwidth 100 kHz
MPX input connectors BNC Female
ASI output connector BNC Female
ASI stream bitrate 9,220 Mbit/s
MPX input level 0-9 dBm
Input impedance 600 Ohm
Control Front Panel
Supply AC: 230 V/50Hz or 110 V/60Hz DC: 22V ÷ 65V
Max consumption 30 W
Width 482 mm
Height 44 mm
Depth 480 mm
Weight 4 Kg
Operative temperature range -10°C÷60°C
Relative humidity 0-95% non condensing
2.2. SRS-02.
Bandwidth 100 kHz
MPX output connector BNC Female
ASI input connector BNC Female
ASI output connector BNC Female
MPX output level 6 dBm (adjustable)
MPX output impedance 600 Ohm
BB bandwidth 0-22 MHz
Maximum tuneable frequency 18MHz
BB output impedance 75 Ohm
BB carrier level -21 dBm
Max carriers 4
Deviation Adjustable step 6 dB
Control Front panel
Supply AC: 230 V/50Hz or 110 V/60Hz
DC: 22V ÷ 65V
Max consumption 30 W
Width 482 mm
Height 44 mm
Depth 480 mm
Weight 4 Kg
Operative temperature range -10°C÷60°C
Relative humidity 0-95% non condensing
SRS-01 SRS-02
Page 5 of 31 Version 2.0
2.3. Loop encoder-decoder.
Bandwidth 100 kHz
MPX
Amplitude/frequency response < 0.1dB
S/N > 76dB
S/N weighted CCIR468.2 > 68dB
Stereo separation > 43dB
THD+N < 0.15%
Decoded Base-Band
Amplitude/frequency response < 0.1dB
S/N > 70dB
S/N weighted CCIR468.2 > 62dB
Stereo separation > 40dB
THD+N < 0.25%
SRS-01 SRS-02
Page 6 of 31 Version 2.0
3. Installation.
1. Open the package box, using a cutting tool, ensuring no damage is done to the
content. Verify any damage caused during transportation.
2. Check the package contents. The package should contain:
a. SRS-01.
b. SRS-02.
c. Two AC power cords.
d. Two DC power cords.
e. User Manual.
3. Install the control units in a cabinet rack. The space required is 1 rack unit.
4. Verify that there is sufficient clearance on both sides of the equipment in order not
to restrict air flow.
5. No heat sources should be placed too close to the equipment: the proper
functioning is warranted for ambient temperature between -5°C to +60°C.
6. Install the power cord and connect to the primary power source.
7. Make the ground connection to the screw located on the rear of the equipment, to
meet the EMC directives. Assure of the right input voltage reading the data on the
user manual or on the adhesive stickers, located on each equipment, that show the
register number.
8. Switch on the power switch of the control units located on the rear of the equipment.
The state and the operations of the device can be checked using the keyboard and
the display following the instructions in the paragraph related to the user interface
4.2.
SRS-01 SRS-02
Page 7 of 31 Version 2.0
4. Theory of operations.
4.1. Block diagram.
REGOLATORE_INGRESSI_AUDIO
Figure 1 - Block Diagram
SRS-01 SRS-02
Page 8 of 31 Version 2.0
As results from the block diagram, the system is composed of two macro-blocks:
1. SRS-01
2. SRS-02
4.1.1. SRS-01.
The SRS-01, as results from the block diagram, is composed of 8 boards:
1. Power Supply
2. Microcontroller_DSL
3. Keypad_CU
4. Regolatore ingressi audio
5. FM_TV_MOD
6. 4MPX_ASI
7. Allarmi_ponti_PVT_RAI
8. Motherboard PM
SRS-01 SRS-02
Page 9 of 31 Version 2.0
4.1.1.1. Power Supply.
The power supply can be:
A.C. 230 V +/-20% 50Hz
115 V +/-10% 60Hz
D.C. 25 ÷ 65 V
Power 60W
The installed power supply protection fuse on the alternating current is 1.6 amps. An
automatic switch is present between the two supplies. In case the A.C. current reaches a
lower threshold, the input supply is switched to D.C. current. The switching occurs
instantaneously without causing any power interruption of the equipment.
The D.C. voltage input connector is a 4 pin connector. The power cable must be
connected to pin 2 and 4, independent of the polarity.
The D.C. input is galvanically isolated from the equipment earth.
Figure 2: D.C. Power Connector.
4.1.1.2. Microcontroller_DSL
The microcontroller aims for following functions:
� Configuring of audio input level.
� Audio levels monitoring.
� Keypad, LCD display, led management.
� Alarms management.
SRS-01 SRS-02
Page 10 of 31 Version 2.0
4.1.1.3. Keypad_CU.
The keypad board is installed directly on the front panel. It is composed of the 24x2
characters LCD display, the 16 Led and the 6 keys for menu scrolling and selection.
4.1.1.4. Regolatore ingressi audio.
This board is equipped with switches, digitally configurable, which enable 4 different
attenuation networks for each input.
4.1.1.5. FM_TV_MOD.
The FM_TV_MOD board is the digital processor; it accepts 4 MPX audio channels as
input.
This compact board performs a full-digital processing of the audio signals generating at the
output, on a parallel interface, the digital data for the 4MPX-ASI board.
4.1.1.6. 4MPX-ASI.
The 4MPX-ASI board accepts as input parallel data generated by the digital processor and
converts them in ASI format with a bitrate of 9.220 Mbit/s.
4.1.1.7. Allarmi_ponti_PVT_RAI.
This board is equipped with 4 relays digitally driven in order to warrant the signalling of bad
functioning or absence of each input channel.
4.1.1.8. Motherboard PM.
The PM motherboard is designed to house up to 4 standard size boards and 2 of reduced
dimensions or 2 standards and 6 smaller sizes. It is also designed to incorporate the
Microcontroller_DSL, Power_supply boards and the voltage transformer. The presence of
the motherboard extensively reduces the use of interconnecting cables which would
otherwise be very complex. It also provides for future upgrades.
SRS-01 SRS-02
Page 11 of 31 Version 2.0
Figure 3 – Mother Board
Smaller boards
Trasformer
Microcontroller
Supply
Standard Boards
SRS-01 SRS-02
Page 12 of 31 Version 2.0
4.1.2. SRS-0.2
The SRS-02, as results from the block diagram, is composed of 8 boards:
1. Power Supply
1. Microcontroller_DSL
2. Keypad_CU
3. FM_TV_DEM
4. ASI-4MPX
5. Motherboard PM
6. Allarmi_ponti_PVT_RAI
7. DAC_Subcarrier
4.1.2.1. Power Supply.
See paragraph 4.1.1.1.
4.1.2.2. Microcontroller_DSL.
The microcontroller aims for following functions:
� Configuring of audio output level.
� Audio levels monitoring.
� Baseband carriers frequency synthesis.
� Baseband carriers deviation regulation.
� Keypad, LCD display, led management.
� Alarms management.
4.1.2.3. Keypad_CU.
The keypad board is installed directly on the front panel. It is composed of the 24x2
characters LCD display, the 16 Led and the 6 keys for menu scrolling and selection.
SRS-01 SRS-02
Page 13 of 31 Version 2.0
4.1.2.4. FM_TV_DEM.
The FM_TV_DEM board is a digital processor which accepts as input a parallel data
stream coming from the ASI-4MPX board.
If the data stream was generated by a SRS-01, the digital processor finds and separates
the data of each channel and sends them to 4 different D/A converter in order to
reconstruct the original MPX signals.
Another function is the generation of a multiplex composed of up to 4 carriers in the 0-18
MHz baseband, modulated by the content of each original MPX channel.
4.1.2.5. ASI-4MPX
The ASI-4MPX board is an ASI receiver which delivers to the digital processor the parallel
data transported by the ASI stream itself.
On the board is installed a PLL circuit driven by the processor in order to lock the VCXO
utilized in the SRS-01 at the digital data generation.
The board generates only the phase error signal, available on a SMB connector to connect
it to the DAC-SC board.
This last board gives back the precise clock to the ASI-4MPX board which uses it as
system master-clock.
4.1.2.6. Motherboard PM.
See par. 4.1.1.8.
4.1.2.7. Allarmi_ponti_PVT_RAI.
See par. 4.1.1.7
SRS-01 SRS-02
Page 14 of 31 Version 2.0
4.1.2.8. DAC_SC.
The DAC-SC board has two functions:
1. It receives on a 26 pin connector the modulated carriers digital data coming from
the processor and sends them to the Tx DAC, to generate the baseband signal,
output of the equipment.
2. It receives the 44,736 MHz VCXO, installed on the board, control voltage from the
ASI-4MPX board, and generates a precise clock, locked to the data, to be used as
master clock. This second function is necessary in order to minimize the Tx DAC
output spurious content.
SRS-01 SRS-02
Page 15 of 31 Version 2.0
4.2. User interface (keypad + display).
The setup, control, and monitoring is provided through the navigation in the embedded
software menu presented on a 24x2 alphanumeric display and operated by a six way
keypad.
The six way keypad enables navigation through the various menus of the embedded
system. The function of the keypad depends on the menu position. A short description
follows:
Configuration menu Keys
Position 1 Other positions Status menu
UP Previous menu Previous menu
DOWN Next menu Next menu
RIGHT Cursor scrolls
one position
to the right
Cursor scrolls one position to
the right
Not used
LEFT No use Cursor scrolls one position to
the left
No use
ENTER Next Menu Saves and applies changes Next Menu
ESC Displays Main
Menu
Discard any changes Displays Main
Menu
Table 1: Menu Description
SRS-01 SRS-02
Page 16 of 31 Version 2.0
Figure 4 – Control Menu
Table 1 – Main menu description
Option Description
Main Menu The name of the equipment, the status
and the number of channels present are
shown.
Version display This menu is automatically shown for
three seconds, after that the display
returns to the main status menu.
It shows the firmware version of the
board installed.
Configuration It lets to change every configuration
parameter of the equipment.
Status It lets to verify the status of each
parameter of the equipment.
SRS-01 SRS-02
Page 17 of 31 Version 2.0
4.2.1. SRS-01.
4.2.1.1. Configuration menu.
The configuration menu let the user to change the equipment parameter.
The Figure 5 shows its tree structure.
Figure 5 – SRS-01 configuration menu tree.
SRS-01 SRS-02
Page 18 of 31 Version 2.0
Table 2 – Configuration menu description
Option Description
Alarm led setting
It sets the alarm condition for which
the front panel ALARM led becomes red.
� ASI unlocked
� No MPX 1
� No MPX 1-2
� No MPX 1-2-3
� No MPX 1-2-3-4
Audio 1 Level Control
It sets the attenuation network which
best matches the MPX input 1 signal
level. Moreover, it shows the encoder
input level as monitor.
Audio 2 Level Control
It sets the attenuation network which
best matches the MPX input 2 signal
level. Moreover, it shows the encoder
input level as monitor.
Audio 3 Level Control
It sets the attenuation network which
best matches the MPX input 3 signal
level. Moreover, it shows the encoder
input level as monitor.
Audio 4 Level Control
It sets the attenuation network which
best matches the MPX input 4 signal
level. Moreover, it shows the encoder
input level as monitor.
SRS-01 SRS-02
Page 19 of 31 Version 2.0
4.2.1.2. Status menu.
The status menu let the user to monitor the equipment performance and status.
Figure 6 - SRS-01 status menu tree.
Table 3 – Menu description
Option Description
MPX1 MPX2
It shows the encoder input levels of MPX
1 and 2.
MPX3 MPX4
It shows the encoder input levels of MPX
3 and 4.
SRS-01 SRS-02
Page 20 of 31 Version 2.0
4.2.2. SRS-02.
4.2.2.1. Initial setting.
At the switch on of the equipment, push LEFT and RIGHT button till the following menu
appears:
“SELECT MF OSCILLATOR: “
“80MHz 90MHz “
Select the up-conversion oscillator utilized for the correct visualization of the synthesized
frequency.
4.2.2.2. Configuration menu.
The configuration menu let the user to change the equipment parameter.
The Figure 7 shows its tree structure.
SRS-01 SRS-02
Page 21 of 31 Version 2.0
Figure 7 - SRS-02 configuration menu tree.
SRS-01 SRS-02
Page 22 of 31 Version 2.0
Table 4 – Configuration menu description.
Option Description
Alarm led setting
It sets the alarm condition for which
the front panel ALARM led becomes red.
� ASI unlocked
� No MPX 1
� No MPX 1-2
� No MPX 1-2-3
� No MPX 1-2-3-4
Audio 1 Level Control
It sets the MPX 1 output level.
To clarify, besides is shown the level
of the signal coded by the SRS-01.
100% correspond to 2190 mV, 6dBm on 600
Ohm.
The regulation is performed in 0.2 dB
step from -6dB up to + 6dB.
Some value can saturate the output
signal, generating distortions.
At 100%, the security margin is 1 dB.
Audio 2 Level Control Idem for MPX 2.
Audio 3 Level Control Idem for MPX 3.
Audio 4 Level Control Idem for MPX 4.
SC1 Frequency
It sets the baseband output carrier 1
frequency, with an offset of 80 or 90
MHz, depending on the external
conversion oscillator frequency.
The permitted bandwidth are:
88-98 MHz (LO = 80 MHz)
98-108 MHz (LO = 90 MHz)
Resolution is 10Hz.
It’s also available the possibility of
disable the carrier.
SC2 Frequency Idem for carrier 2.
SC3 Frequency Idem for carrier 3.
SC4 Frequency Idem for carrier 4.
SC1 Deviation It sets the deviation sensibility of
carrier 1.Values are referred to 100% of
modulation and have 6dB step.
SC2 Deviation Idem for carrier 2.
SC3 Deviation Idem for carrier 3.
SC4 Deviation Idem for carrier 4.
SRS-01 SRS-02
Page 23 of 31 Version 2.0
4.2.2.3. Status menu.
The status menu let the user to monitor the equipment performance and status.
Figure 8 shows the tree structure.
Figure 8 - SRS-02 status menu tree.
Table 5 - SRS-02 status menu description
Option Description
MPX1 MPX2
It shows the encoder input 1 and 2
levels.
MPX3 MPX4
It shows the encoder input 3 and 4
levels.
SRS-01 SRS-02
Page 24 di 31 Version 2.0
RS-232
Connector
LED
LED
6 buttons
keypad
Display LCD
24x2
5. External Description.
5.1. SRS-01.
5.1.1. Front Panel.
Figure 9 - SRS-01 Front Panel
SRS-01 SRS-02
Page 25 of 31 Version 2.0
5.1.1.1. Indicators and controls.
Item Description
LED Green: equipment switched on
AUDIO1 AUDIO2 AUDIO3 AUDIO4 BASEBAND DVB-ASI ALARM
GREEN ORANGE RED
MPX 1 present MPX 1 level higher
than 115% of
standard value
(2190mV or 6dBm on
600 Ohm)) or lower
than 9%
MPX 1 absent
MPX 2 present
Idem for MPX 2 MPX 2 absent
MPX 3 present
Idem for MPX 3 MPX 3 absent
MPX 4 present
Idem for MPX 4 MPX 4 absent
Not used
Not used Not used
Encoder ok Not used Encoder not
running
The equipment
respects the
conditions set
by user
interface
Not used The equipment
doesn’t respect
the conditions
set by user
interface
6 buttons keypad
Keypad used for menu browsing
LCD Display alphanumeric 24×2
5.1.1.2. Connectors description.
RS232: Firmware uploading DB9 connector.
� Pin 2 Rx
� Pin 3 Tx
� Pin 5 Ground
� Other pins not connected.
SRS-01 SRS-02
Page 26 of 31 Version 2.0
Ground
AC connector
Fuse box
MPX input
connectors
DVB-ASI
Connectors DC connector
Network
switch on/off Alarms
contacts
5.1.2. Rear panel.
Figure 10 - SRS-01 Rear panel
SRS-01 SRS-02
Page 27 of 31 Version 2.0
5.1.2.1. Connectors description.
Connector Description
Connectors Connector Description
MPX 1 MPX input connector, BNC
MPX 2 MPX input connector, BNC
MPX 3 MPX input connector, BNC
MPX 4 MPX input connector, BNC
ASI OUT ASI output connector, BNC
ASI AUX ASI output connector, BNC Alarms contacts Pin 1: OPEN -> NO MPX 1
CLOSED -> MPX 1 OK
Pin 2: OPEN -> NO MPX 2
CLOSED -> MPX 2 OK
Pin 3: OPEN -> NO MPX 3
CLOSED -> MPX 3 OK
Pin 4: OPEN -> NO MPX 4
CLOSED -> MPX 4 OK
DC Connector Input 25÷65 V DC.
Network switch on/off ON/OFF of the equipment
Fuse box 230V 1.6A
AC Connector 230V 50/60Hz – 115V 50/60Hz
SRS-01 SRS-02
Page 28 of 31 Version 2.0
Connector
RS-232
LED
LED
6 buttons
keypad
Display LCD
24x2
5.2. SRS-02.
5.2.1. Front Panel.
Figure 11- SRS-02 front panel.
SRS-01 SRS-02
Page 29 of 31 Version 2.0
5.2.1.1. Indicators and controls.
Item Description
LED Green: equipment switched on
AUDIO1 AUDIO2 AUDIO3 AUDIO4 BASEBAND DVB-ASI ALARM
GREEN ORANGE RED
MPX 1 present MPX 1 level
higher than
115% of
standard value
(2190mV or 6dBm
on 600 Ohm)) or
lower than 9%
MPX 1 absent
MPX 2 present
Idem for MPX 2 MPX 2 absent
MPX 3 present
Idem for MPX 3 MPX 3 absent
MPX 4 present
Idem for MPX 4 MPX 4 absent
At least one
carrier enabled
Not used No base band carrier
enabled
Decoder locked Not used Decoder unlocked, no
ASI at input.
The equipment
respects the
conditions set by
user interface
Not used The equipment doesn’t
respect the conditions
set by user interface
6 buttons keypad
Keypad used for menu browsing
LCD Display alphanumeric 24×2
5.2.1.2. Connectors description
RS232: DB9 connector for serial communication
�
� Pin 2 Rx
� Pin 3 Tx
� Pin 5 GND
� Other Pin not connected
SRS-01 SRS-02
Page 30 of 31 Version 2.0
General
Ground
AC Connector
Fuse box
MPX output
connector
DVB-ASI
connectors DC Connector
Network
On/off switch Relay
contacts
Baseband
output
connector
5.2.2. Rear panel
Figure 12 - SRS-02 Rear Panel
SRS-01 SRS-02
Page 31 of 31 Version 2.0
5.2.2.1. Connectors description.
Connector Description
Connectors Connector Description
MPX 1 Output connector MPX, BNC
MPX 2 Output connector MPX, BNC
MPX 3 Output connector MPX, BNC
MPX 4 Output connector MPX, BNC
ASI IN ASI input connector BNC
ASI OUT ASI output recovered, BNC
BB OUT BB connector, BNC Relay connector Pin 1: OPEN -> NO MPX 1
CLOSED -> MPX 1 OK
Pin 2: OPEN -> NO MPX 2
CLOSED -> MPX 2 OK
Pin 3: OPEN -> NO MPX 3
CLOSED -> MPX 3 OK
Pin 4: OPEN -> NO MPX 4
CLOSED -> MPX 4 OK
DC Connector Input 25÷65 V DC.
Network On/off switch
Equipment ON/OFF
Fuse box 230V 1.6A
AC Connector 230V 50/60Hz 115 50/60Hz