Prevail-Catv WT-1550-DM User manual

WT-1550-DM
Intelligent Direct Modulated
Optical Transmitter Operating Manual

WT-1550-DM Intelligent Direct Modulated Optical Transmitter
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Table of Contents
Table of Contents ...................................................................................................... - 1 -
1. Overview............................................................................................................... - 2 -
1.1 About This Manual ...................................................................................... - 2 -
1.2 Product Description ..................................................................................... - 2 -
1.3 Product Applications .................................................................................... - 3 -
2. Technique Parameters ........................................................................................... - 4 -
3. Panel Interface and Menu System Description ..................................................... - 5 -
3.1 Front Panel ................................................................................................... - 5 -
3.1.1 Indicator Description ......................................................................... - 5 -
3.2 Rear Panel .................................................................................................... - 6 -
3.3 Power Module.............................................................................................. - 6 -
3.3.1 220V Power Module .......................................................................... - 6 -
3.4 Menu Operation ........................................................................................... - 7 -
3.4.1 Main Menu......................................................................................... - 7 -
3.4.2 Display Menu..................................................................................... - 8 -
3.4.3 Set Menu .......................................................................................... - 10 -
3.4.4 Alarm Menu ..................................................................................... - 11 -
4. Installing the WT-1550-DM Optical Transmitter ............................................... - 12 -
4.1 Receiving and Inspecting........................................................................... - 12 -
4.2 Precautions ................................................................................................. - 12 -
4.3 Mounting WT-1550-DM............................................................................ - 12 -
4.3.1 Mounting the WT-1550-DM in the Rack......................................... - 12 -
4.3.2 Connecting the RF Cables ............................................................... - 12 -
4.3.3 Connecting the Optical Fiber Cables ............................................... - 13 -
4.3.4 Connecting the Ethernet Cable ........................................................ - 13 -
4.3.5 Connecting Power ............................................................................ - 13 -
5. Communication Setup......................................................................................... - 14 -
5.1 RS232 Communication Interface Description ........................................... - 14 -
5.2 Set up the Hyper Terminal ......................................................................... - 14 -
5.3 Operating Parameters Configuration ......................................................... - 16 -
5.4 Remote Monitoring: SNMP....................................................................... - 19 -
6. Maintenance and Troubleshooting...................................................................... - 20 -
6.1 Cleaning Fiber Optic Connectors............................................................... - 20 -
6.1.1 Cleaning Patch Cord or Pigtail Fiber Optical Connectors ............... - 20 -
6.2 Troubleshooting ......................................................................................... - 21 -
6.3 After-sales Service Description.................................................................. - 21 -
6.4 Disclaimer .................................................................................................. - 21 -

WT-1550-DM Intelligent Direct Modulated Optical Transmitter
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1. Overview
1.1 About This Manual
This instruction manual is a complete guide to install and operate the (1RU)
WT-1550-DM optical transmitter. Please read the entire manual before beginning
installation.
This manual applies to WT-1550-DM optical transmitter.
• Chapter 1 gives general information about the WT-1550-DM optical transmitter.
• Chapter 2 describes the complete technical specifications of WT-1550-DM.
• Chapter 3 describes the front/rear panel interfaces and menu system.
• Chapter 4 tells you how to install WT-1550-DM optical transmitter.
• Chapter 5 tells you the communication setting of WT-1550-DM.
• Chapter 6 describes maintenance and what to do in the event of problems.
1.2 Product Description
WT-1550-DM intelligent directly modulated optical transmitter is mainly used in
1550nm optical fiber transmission system. Adopt advanced electronic dispersion
compensation technology, accurately compensate according to the actual transmission
distance by 1km stepping. The maximum compensated distance up to 50km.
WT-1550-DM intelligent directly modulated optical transmitter is the most
important equipment to construct the CATV network. It mainly used for the
value-added services of TV image signal, digital television signal, telephone voice
signal and data (or compressed data) signal. By built-in WDM, multiplex the inter-cut
optical signal and the main optical signal then output. After setting required optical
difference, the perfect adjustable optical attenuation function can automatic control
the inserted optical signal according to the main optical signal, realize inter-cut system
full automatic adjustment. Provide high quality low cost solution for all-optical relay
1550 optical fiber CATV system, and local value-added services inter-cut.
Characteristics:
1. Patent pre-distortion circuit.
2. The optical fiber distance is adjustable according to the actual use condition by
1km stepping.
3. WT-1550-DMⅡ: Built-in WDM, multiplex the inserted optical signal and the
main optical signal then output.
4. WT-1550-DM Ⅲ: Built-in WDM and adjustable attenuator.

WT-1550-DM Intelligent Direct Modulated Optical Transmitter
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Block Diagram
WT-1550-DM directly modulated optical transmitter block diagram
WT-1550-DM inter-cut part block diagram
1.3 Product Applications
• 1550nm Optical fiber transmission system
• Construct the CATV network
• Local value-added services inter-cut

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2. Technique Parameters
Item Unit Technique Parameters
Output optical power mW 10
Optical wavelength nm 1550±10 (have to be ITU wavelength when
with inter-cut function)
Dispersion compensation
distance Km ≤50
Laser type DFB laser
Optical modulation mode Direct optical intensity modulation
Optical connector type FC/APC or SC/APC
Frequency range MHz 47-862/1003
RF input level dBuV 75-85
Flatness in band dB ±0.75
RF input impedance Ω 75
Input return loss dB ≥ 16
C/CSO dB ≥ 60 25Km optical fiber, 0dB
received
C/CTB dB ≥ 65
C/N dB ≥ 51
AGC control range dB ±5
MGC control range dB 0-20
Supply voltage V AC 110V-250V (50Hz)
Consumption W 30
Operating temperature ℃ 0 -- 45
Storage temperature ℃ -20 -- +65
Relative humidity % Max 95% no condensation
Dimension mm 483（L）×380（W）×44（H）
Special instructions: The performance parameters of this manual according to the
measuring method of GY/T 143-2000 <Specifications and methods of measurement
on AM optical transmitter and receiver used in CATV systems>, and tested under the
specified test conditions.

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3. Panel Interface and Menu System Description
3.1 Front Panel
Front panel schematic diagram
1 Power indicator 2 Running indicator 3 Laser indicator
4 RF input indicator 5 LCD 6 ESC key
7 UP key 8 DOWN key 9 Enter key
10 RF output test port 11 Laser switch
3.1.1 Indicator Description
Power indicator (POWER) Power on LED green
Running indicator (RUN) Run normally LED flash green
Lase
r
indicato
r
Laser OFF LED red
Laser ON LED green
RF in
p
ut indicator
(
RF
)
No output or exceed the normal range LED flash red
Normal LED green
11

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3.2 Rear Panel
Rear Panel schematic diagram
No. Name Remark
1 Fan
2 RF input
3 Local RF input Generally reserved
4 Ground stud Used for the connection of device and ground wire
5 Optical input Inserted optical signal input (without inter-cut function, no this port)
6 Optical signal
output
This interface is the optical signal output port of the device (If select
inter-cut function, this port is mixed output)
7 RS232 interface Used for configuring the network management parameters.
8 LAN interface Correspond to IEEE802.3 10Base-T, used for network management.
9 Switching power
supply
Hot plug
3.3 Power Module
3.3.1 220V Power Module
1 Mounting screws 2220V/110V power outlet 3 Fuse
4 Power switch
1 2 3 4 567899

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In: 0.0
dBuV
Out:10.3
dBm Enter
1. Dis
p
Parameters
ESC
2.Set Parameters
3.Alarm Status
3.4 Menu Operation
3.4.1 Main Menu
Displayed parameters Comments
Boot display
1.Disp Parameters Menu one: Display parameters
2.Set Parameters Menu two: Set parameters
3.Alarm Status Menu three: Alarm status

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3.4.2 Display Menu
Laser Temp: xx.x℃
BOX Temp: xx.x℃
1.Dis
p
Parameters Enter
Laser Power:
xx.xdBm
OP After ATT: xx.xdBm
Laser Bais: xx.xmA
In
p
ut Power: -xx.xdBm
Tec Current: -x.xxA
RF Chan NO: 1
Laser RF:
xdBuV
RF Ctrl Mode: MGC
RF Control Mode: AGC
MGC ATT: XdB
AGC Ref: xdB
Wave Len
g
th: xxxx.xnm
ESC
+5V Read: x.xxV
-5V Read:
-x.xxV
+24V Read: xx.xxV
S/N: xxxx.xx.xx
IP : xxx.xxx.xxx.xxx
Msk: xxx.xxx.xxx.xxx
GTW: xxx.xxx.xxx.xxx
Mac: XX-XX-XX-XX-XX-XX
SofteWare Ver: VX.X

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Displayed parameters Comments
Laser Power Laser output optical power
OP After ATT Optical power after attenuation
(without inter-cut function, no this menu)
Input Power External optical signal power
(without inter-cut function, no this menu)
Laser Bais Laser bias current
Laser Temp Laser temperature
Tec Current Cooler current
RF Chan NO Channel number
Laser RF Laser RF power
RF Ctrl Mode RF control mode
MGC ATT MGC attenuation (in MGC mode)
AGC Ref AGC deviator (in AGC mode)
Wave Length Wavelength
+5V Read +5V monitoring voltage
-5V Read -5V monitoring voltage
+24V Read +24V monitoring voltage
S/N Serial number
BOX Temp Temperature
IP IP
Msk Subnet mask
GTW Gateway
Mac MAC address
SofteWare Ver Version number

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3.4.3 Set Menu
Set OPT Delta
2.Set Parameters Enter
Set LaserOutPut Unit
mW dbm
Set Buzzer Alarm
YES NO
Set RF Control Mode
AGC MGC
Set
MGC ATT 0dB
Set
AGC Re
f
xdBm
ESC
Set PredATT Mode Auto
Manu
Set FiberC Len
g
th
0Km
Set Channel Number x
Set Local IP Address
xxx.xxx.xxx.xxx
Set SubNet Mas
k
xxx.xxx.xxx.xxx
Set GateWa
y
xxx.xxx.xxx.xxx
Restore Factor
y
YES NO
+
Set OPT ATT Mode Auto
Manu
Set OPT ATT 0dB
0dB

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Displayed parameters Comments Remarks
Set LaserOutPut Unit Set the unit of output optical
power
Set Buzzer Alarm Set the buzzer alarm YES is on, NO is off
Set RF Control Mode Set the RF control mode AGC and MGC two modes selectable
Set MGC ATT Set the ATT in MGC mode Adjustable range 0~20dB
Set AGC Ref Set the deviator in AGC mode Adjustable range ±3dB
Set PredATT Mode
Set the predistortion control
mode
Two modes:
Auto is automatic control mode; Manu is
manual control mode.
Set FiberC Length Set the transmission distance in
automatic control mode
1km stepping
Set Channel Number Set the channel number
Set Local IP Address Set the IP address
Set SubNet Mask Set the subnet mask
Set GateWay Set the gateway
Restore Factory Restore factory settings
Set OPT ATT Mode Set the optical power ATT
mode
Without inter-cut function, no this menu
Set OPT ATT Set the optical power
attenuation
Without inter-cut function, no this menu
Set OPT Delta
Set the difference between the
main optical power and the
inserted optical power
Without inter-cut function, no this menu
3.4.4 Alarm Menu
The displayed alarm content Comment
RF Alarm RF alarm
Laser Temp Laser temperature alarm
Laser Bais Laser bias current alarm
Laser Tec Laser cooling current alarm
Output Alarm Output optical power alarm
+5V Alarm +5V alarm
-5V Alarm -5V alarm
+24V Alarm +24V alarm

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4. Installing the WT-1550-DM Optical Transmitter
4.1 Receiving and Inspecting
As you unpack your unit, inspect the shipping container and equipment for damage.
Save the shipping material for future use. If the container or the equipment is
damaged, notify both the freight carrier and us.
4.2 Precautions
Heed the following precautions when working with the WT-1550-DM.
4.3 Mounting WT-1550-DM
4.3.1 Mounting the WT-1550-DM in the Rack
Mounting the WT-1550-DM in the standard 19 inch equipment rack:
1. Place the equipment in the rack.
2. Use four screws fixed the mounting lug on the WT-1550-DM front panel to the
rack.
3. Reliably ground the equipment. The ground terminal is on the rear panel.
4. Visually inspect each key (button) on the front panel to ensure that it is not trapped
under the edge of its hole. If a key is trapped, tap the key to enable it to move freely.
4.3.2 Connecting the RF Cables
Verify the RF input F connector type according to the ordering information, then
screw on the matched RF cable.
Warning
The plug-socket combination must be accessible at all
times, because it serves as the main disconnecting device.
Warning
Read the installation instructions before connecting the
system to the power source.
CAUTION: To protect yourself from potential injury and to protect
the equipment from further damage, do not perform any
operational tests if the equipment appears to be damaged.

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4.3.3 Connecting the Optical Fiber Cables
WT-1550-DM has one or two optical connectors.
1. Verify the matched WT-1550-DM fiber cable connector type according to the
ordering information.
2. Verify that the fiber cable connector has been cleaned properly. If the fiber cable
connector needs to be cleaned, follow the cleaning procedure outlined in “Cleaning
Patch Cord or Pigtail Fiber Optical Connectors”.
3. Ver if y t ha t the WT-1550-DM optical connector has not been exposed to any
contamination.
NOTE: Any contamination of optical connector can significantly
degrade optical link performance. This degradation will most likely
manifest itself as poor signal-to-noise (SNR) performance.
4. Note to butt the nick of the connectors and align them accordingly.
4.3.4 Connecting the Ethernet Cable
You can connect the WT-1550-DM to your TCP/IP network in order to monitor and
control the transmitter remotely. After you complete the installation procedures
described in this chapter, you can use a network management system (NMS) to
monitor and control the WT-1550-DM.
To connect the WT-1550-DM, you must use a shielded and grounded Category 5
Ethernet cable.
To connect the Ethernet cable:
1. Connect an Ethernet cable to the transmitter’s RJ-45 Ethernet port. The Ethernet
port is on the rear panel of the transmitter.
2. Verify that the green Link LED is illuminated, indicating that there is a connection.
4.3.5 Connecting Power
The WT-1550-DM is available in an AC220V power model. After mounting the
WT-1550-DM in a rack, follow the power connection procedure below for the model
that you are installing.
Can be equipped with two 220V power supply that requires input voltage 150～
265VAC, at 50～60Hz single phase. The AC power plug is located on the rear panel.
Turn on the power source. It takes about 60 seconds for all systems to operate.
DANGER: The fiber carries invisible laser radiation. AV O I D
DIRECT EXPOSURE TO BEAM. Never operate the unit with a
broken fiber or with a fiber connector disconnected.

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5. Communication Setup
5.1 RS232 Communication Interface Description
Adopt DB9 standard connector, the pin definitions as follow:
1: No Connect
2: TX
3: RX
4: No Connect
5: GND
6: No Connect
7: No Connect
8: No Connect
9: No Connect
The serial communication uses the standard NRZ form, 1 starts bit, 8 data bits, 1
stop bit and the baud rate is 38400.
5.2 Set up the Hyper Terminal
If you have not setup the Hyper Terminal in your Windows system, follow the steps:
Click “start menu programaccessorycommunicationHyper Terminal”:
This results in the following screen:
Then you input your connection name, such as “SNMP38400”，and choose the serial
port to connect with your equipment. As follows:

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Press the “OK” button shows the configuration page of serial port. As follows:
Change the serial port configuration to 38400-baud rate, 8 data bits, no parity bit, 1
stop bit, no data flow control, press the “OK” button, you have set up the Windows
serial port Hyper Terminal.
You can click “filesave” menu to save this configuration of Hyper Terminal for
later using.

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5.3 Operating Parameters Configuration
Under the condition of power off, use the serial port lines to connect the RS232 port
with the computer port. Open the Windows Hyper Terminal which you have set up.
Then turn on the power, you will see the page as follows. Enter the password to enter
the configuration interface.
Enter the password, display the following screen:
You can input your command in this page, and then configure the operating parameter
of the application program.

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WT-1550-DM Intelligent Direct Modulated Optical Transmitter
System supports the following commands:
help
ethcfg
settrap
community
Restore
setsn
setpswd
entplogo
Exit
List internal commands of the system;
Configure the Ethernet operating parameters;
Configure the aim host IP address of the SNMP Trap;
Configure the SNMP group name;
Restore the factory default values;
Set the serial number;
Set the login password;
Set the logo and equipment model;
Log out.
Specific using as follows:
help
This command shows current application program version, program name and the
internal commands list of the system as follows:
You can also use the “help” command to show help information of other commands,
such as “help ethcfg”，ethcfg’s help information appears as follows:

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WT-1550-DM Intelligent Direct Modulated Optical Transmitter
ethcfg
This command configures the Ethernet parameters, including IP address, subnet mask
and gateway. You can refer to the help information for its using.
settrap
This command shows or modifies the aim host IP address list of the SNMP Trap,
IP address of 0.0.0.0 and 255.255.255.255 don’t exist. SNMP Trap does not send to
these two addresses.
community
This command configures the read-only group name and read-write group name.
“Group name” is the concept of SNMP agreement like the password. Use the
command “community ro” to configure the read-only, and “community rw” for the
read-write. For example, input “community rw public”, “public” is the read-write
group name. The group name for read-only and read-write are both “public” as the
equipment default setting from factory.
setpswd
This command is used to modify the login password.
entplogo
This command is used to set the logo and equipment model.
Exit
This command is used to log out.

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WT-1550-DM Intelligent Direct Modulated Optical Transmitter
5.4 Remote Monitoring: SNMP
LAN communication interface
Adopt RJ45 standard connector, the pin definitions as follow:
1: TX+
2: TX-
3: RX+
4: No Connect
5: No Connect
6: RX-
7: No Connect
8: No Connect
A: Green indicator flashing means that the LAN port is sending data.
B: Yellow indicator means that the network connection is normal.
SNMP basic background
Simple Network Management Protocol (SNMP) is an application layer protocol.
It makes the management information between network devices exchange easier. It is
part of the TCP / IP protocol group. SNMP enables the end-users to manage network
performance, find and solve network problems, and arrange for future network
upgrades.
Management Information Base (MIB) is the organized hierarchical information
set. Use SNMP to visit these MIB. They are composed of manageable information,
and identified by the object identifier.
SNMP
Transmitter configuration of network communication
When the transmitter initial work, the IP address and gateway are in the default
state, you need to configure them. The configuration of initial state can be achieved
through the RS-232 interface or the front panel keys. Other configurations see our
<Network management operation manual>.