Raisecom RC801-30B-FV35-M User manual

RaisecomTechnologyCo.,Ltd. http://www.raisecom.com
- 1 -
RC801-30B-FV35, RC803-30B-FV35,
RC805-30B-FV35 Series
Standalone N×64K V.35 Interface
Fiber Optic Modem
User Manual
20041008
Raisecom Technology Co., Ltd.

RaisecomTechnologyCo.,Ltd. http://www.raisecom.com
- 2 -
CONTENTS
CHAPTER 1. INTRODUCTION..........................................................................................................3
1.1 MAIN FEATURES ..............................................................................................................................3
1.2MODEL DISCRIPTION ........................................................................................................................3
1.3PRODUCT SPECIFICATIONS ...............................................................................................................4
1.3.1 Fiber Optic Interface Specification.........................................................................................4
1.3.2 E1 Data Channel.....................................................................................................................4
1.3.3 V.35 Interface Specification.....................................................................................................4
1.3.4 V.35 Signal Bandwidth Engrossment of Timeslots at E1 Fractional Mode .............................5
1.3.5 Power Supply ..........................................................................................................................5
1.3.6 Ambience.................................................................................................................................5
1.3.7 Dimensions..............................................................................................................................5
CHAPTER 2. RECOMMENDED CONNECTION TYPE.................................................................6
2.1 PRECAUTIONS BEFORE CONNECTION...............................................................................................6
2.1.1 Three Types of Timing Resource..............................................................................................6
2.1.2 Compatibility...........................................................................................................................6
2.2 BASIC CONNECTION TYPE...............................................................................................................6
2.2.1 Point-to-point, ‘Master Clock – Slave Clock’Topology..........................................................6
2.2.2 Point-to-point, ‘Terminal Clock – Slave Clock’Topology.......................................................7
2.3 EXTENDED CONNECTION TYPE .......................................................................................................7
CHAPTER 3. PREPARATION.............................................................................................................8
3.1 DESCRIPTION OF THE FRONT AND BACK PANEL...............................................................................9
3.1.1 Definition of the Indicators.....................................................................................................9
3.1.2 Fiber Optic Interface.............................................................................................................10
3.13 LOOP SW loop-back setting switch .......................................................................................10
3.1.5 V.35 (DCE) Interface.............................................................................................................11
3.2 DIP-SWITCH SW1 SETUP ON THE BOTTOM PANEL .........................................................................11
3.2.1 The 1st ~ 5th Bit: V.35 Interface Bandwidth Setup..................................................................12
3.2.2 The 6th Bit: V.35 Bandwidth Control Option..........................................................................13
3.2.3 The 7th and 8th Bits: Timing Resource Option........................................................................14
3.2.4 The Factory Default Setup of SW1: All OFF.....................................................................14
3.3 DIP-SWITCH SW2 SETUP ON THE BOTTOM PANEL .........................................................................14
3.3.1 The 1st ~ 4th Bits Definition....................................................................................................14
3.3.2 The Factory Default Status of SW2: All OFF........................................................................15
CHAPTER 4. INSTALLATION AND TROUBLESHOOTING......................................................15
4.1 CAUTIONS BEFORE APPLYING THE POWER SUPPLY........................................................................15
4.2 CONNECTION DIAGNOSIS .......................................................................................................15
4.3 FAULT-PASS-THROUGH FUNCTION...........................................................................................16
4.4 FAQS......................................................................................................................................16

RaisecomTechnologyCo.,Ltd. http://www.raisecom.com
- 3 -
Chapter 1. Introduction
RC801/803/805-30B-FV35 series standalone N*64kbps V.35 interface fiber optic modems are
devices that are deployed to transmit V.35 signals on fiber optics. They are widely used equipment
in constructing Wide Area Networks, and provide solutions for connecting Routers distantly. This
equipment is the standalone equipment at the Customer Premises, the corresponding centralized
module on the Central Office is RC802-30B-FV35 and RC804-30B-FV35.
The REV.M edition hardware is the upgrade of REV.A, and it adds the Remote Management
function. When using it with module RC802-30B-FV35(REV.M), they could both be managed by
C.O., and set the loop-back at any direction.
1.1 Main features
zUse the ITU-T G.704 frame structure to realize the interface bandwidth adjustment.
zProvide three clock mode: Master clock, Slave clock, and V35 Terminal clock
zFault-pass-through function: divert the warning from the optical receiving side and problem
from the transmitting side to DCD and CTS signal of the V.35 interface.
zThe corresponding relation of the transmitting & receiving data and clock of the V.35
interface could be chosen according to different brands of Router requirement.
zWhen E1 is in the transparent mode, the bandwidth of V.35 interface is 2048Kbps
zWhen E1 is in the fractional mode, the bandwidth of V.35 interface could be set to
N×64Kbps（N=1~31）
zWhen E1 is in the fractional mode and works in pairs, E1 interface could have loop-back
test.
zWhen E1 is in the fractional mode and works in pairs, the remote bandwidth could follow
the C.O. bandwidth setting.
1.2Model discription
Part Number Description
RC801-30B-FV35-M(REV.M)
Standalone at the Customer Premises, N*64Kbps(N=1 ～ 32)V.35-DCE interface ， MM(DSC) ， 0-2km
RC801-30B-FV35-S1(REV.M)
Standalone at the Customer Premises ， N*64Kbps(N=1 ～ 32)V.35-DCE interface ， SM(DSC) ， 0-25km
RC801-30B-FV35-S2(REV.M)
Standalone at the Customer Premises ， N*64Kbps(N=1 ～ 32)V.35-DCE interface ， SM (DSC) ， 10-60km
RC801-30B-FV35-S3(REV.M)
Standalone at the Customer Premises ， N*64Kbps(N=1 ～ 32)V.35-DCE interface ， SM (DSC) ， 15-120km
RC803-30B-FV35-S1(REV.M)
Standalone at the Customer Premises ， N*64Kbps(N=1 ～ 32)V.35-DCE interface ， SM Single strand 1310(SC-PC) ， Dual WL 0-25km
RC803-30B-FV35-S2(REV.M)
Standalone at the Customer Premises ， N*64Kbps(N=1 ～ 32)V.35-DCE interface ， SM Single strand 1310(SC-APC) ， Dual WL 0-60km

RaisecomTechnologyCo.,Ltd. http://www.raisecom.com
- 4 -
RC805-30B-FV35-S1(REV.M)
Standalone at the Customer Premises ， N*64Kbps(N=1 ～ 32)V.35-DCE interface ， SM Single WL1550(SC-PC) ， Dual WL ， 0-25km
RC805-30B-FV35-S2(REV.M)
Standalone at the Customer Premises ， N*64Kbps(N=1 ～ 32)V.35-DCE interface ， SM Single WL1550(SC-APC) ， Dual WL ， 0-60km
1.3Product Specifications
1.3.1 Fiber Optic Interface Specification
Bit rate: 100Mbps
Line code: 4B5B
Fiber connecter: SC
Optical Transmission of single-strand fiber:
Transmit power: ≥-15 dBm
Receiving sensitivity: ≤-31 dBm
Transmit Wavelength: 1310/1550nm
Distance: See the description
Optical Transmission of dual-strand fiber:
Transmit power: ≥-5 dBm
Receiving sensitivity: ≤-35 dBm
Transmit Wavelength: 1310nm
Distance: See the description
1.3.2 E1 Data Channel
Bit rate: 2048Kbps±50ppm
Frame structure: Complies with ITU-T G.704 suggestion
Gitter: Complies with ITU-T G.823 suggestion
Function Characteristics: Complete wire warning indicator, fault-pass-through, and intelligent
automatic replacement function.
1.3.3 V.35 Interface Specification
Physical characteristics: Complies with V.35 interface standard
Connector type：ISO2593 female connector (34-pin female)
Working mode：DCE
Interface bit rate：V.35 interface bit rate is N×64Kbps（N=1~31）at E1 fractional
mode; V.35 interface bit rate is 2048Kbps at E1 transparent
mode

RaisecomTechnologyCo.,Ltd. http://www.raisecom.com
- 5 -
1.3.4 V.35 Signal Bandwidth Engrossment of Timeslots at E1
Fractional Mode
The engrossment of timeslots in PCM31
In PCM31, N ≤31, No. 0 timeslot is taken up by the system. N is calculated from 1 timeslot.
TS[1] TS[N]
…… …… TS[31]
V.35 BANWIDTH
TS[0]
The engrossment of timeslots in PCM30
In PCM30, N ≤30, No. 0 and No. 16 timeslots are taken up by the system. N shall be counted
from No. 1 timeslot, and No. 16 timeslot shall be skipped if N is larger than 16.
TS[1] …… …… TS[31]
V.35 BANWIDTH
TS[N+1] …… TS[0] TS[16]
1.3.5 Power Supply
Power Supply: DC –48V, tolerance range from –36V to –72V
DC +24V, tolerance range from +18 to +36V
AC 220V, tolerance range from 165V to 265V
Power Consumption: ≤5W
1.3.6 Ambience
Working Temperature: 0 ~ 45℃
Humidity: 5%-90% (No condensation)
1.3.7 Dimensions
Standalone equipment can be placed on the table.
Dimension: 142 (width) x 38 (height) x 178 (depth) mm

RaisecomTechnologyCo.,Ltd. http://www.raisecom.com
- 6 -
Chapter 2. Recommended Connection Type
2.1 Precautions before Connection
2.1.1 Three Types of Timing Resource
Master Clock Mode: The timing resource is provided by the crystal oscillator inside the
equipment, also called Internal Clock.
Slave Clock Mode: The timing resource is provided by recovering the clock from the fiber
optic receiving link, also called Restoring Clock.
Terminal Clock Mode: The timing resource is provided by the DTE, also called System
Clock.
2.1.2 Compatibility
The optical interface of those products must be connected to products from Raisecom.
If RC801/803/805-30B-FV35 is connected with G.703 interface fiber optic modem, and then
connected with other brand name E1 fractional mode equipment (i.e. V.35 to fractional E1
interface converter, E1 interface Router); or such equipment as DXC and MUX is serially
connected in the E1 link, the following requirements shall be noticed.
1. PCM30/31 format must be the same
2. The status of CRC enable/disable function must be the same
3. The V.35 signal bandwidth engrossment of G.704 frame pattern must match
4. Ensure that there is only one timing resource in the whole link. Other PCM equipment shall
be configured to Slave Clock Mode (following the link clock).
2.2 Basic Connection Type
The connection topologies introduced in this part is only for user reference. Users are advised to
design and deploy the most appropriate topology according to their specific environment.
2.2.1 Point-to-point, ‘Master Clock – Slave Clock’Topology
When connecting Routers or other V.35 interface equipment point to point, Routers shall work as
DTE. For the convenience of installation and test, it is advised to set the local modem ‘Master
Clock Mode’, and remote modem ‘Slave Clock Mode’. That is, the timing resource is from the
local modem.
When using the structure, if PCM equipment is serially connected in the E1, they are all ‘Slave
clock’(following the E1 line clock).

RaisecomTechnologyCo.,Ltd. http://www.raisecom.com
- 7 -
2.2.2 Point-to-point, ‘Terminal Clock – Slave Clock’
Topology
When the remote DTE must follow the timing resource of local DTE (the TX Clock is Internal
Clock in local DTE), it is advised to set the local RC801-30B-FV35 Terminal Clock, and remote
RC801-30B-FV35 Slave Clock Mode.
When using the structure, if PCM equipment is serially connected in the E1,the other equipment
should be ‘Slave clock’(following the E1 line clock).
2.3 Extended Connection Type
RC801/803/805-30B-FV35 cannot be interconnected with other brand name V.35 interface fiber
optic modems. However, users can adopt RC802-30B series E1 fiber optic modem, which will
convert the optical signals to G.703 compliant E1 electrical signals, and then, connect with a V.35
to fractional E1 interface converter. Users can adopt Raisecom series interface converters such as
RC903-V35FE1 and RC904-V35FE1, and also other brand name interface converters.

RaisecomTechnologyCo.,Ltd. http://www.raisecom.com
- 8 -
When connecting to the ATM equipment, please notice that the CRC at the E1 interface of some
ATM equipment is forbidden, but the CRC of the default mode of this equipment is open, so the
attribute of CRC need to be adjusted to the same. ATM has the default Master clock, so the clock
of this equipment should be adjusted to the Slave clock.
If deploying E1 interface Router at the remote site, RC802-30B E1 fiber optic modem can be
adopted at the remote site as the following diagram. It is advised that if the Router is set to Master
Clock, then the RC801-30B-FV35 at local site shall be set to Slave Clock.
Chapter 3. Preparation
Please read this chapter carefully before installing the equipment.

RaisecomTechnologyCo.,Ltd. http://www.raisecom.com
- 9 -
3.1 Description of the Front and Back Panel
Figure of the front panel
Figure of the back panel
3.1.1 Definition of the Indicators
PWR. Power supply indicator (green): Steady on, built-in power works in good condition.
At the right side of the Optical port, the working status indicators are divided into upper
row(L) and lower row(R), L is the warning or working status indicator from the local
equipment, R is the warning or working status indicator from the remote or opposite
equipment
LOS. Signal loss alarm in optical link (red): ON, when receiving optical link is disconnected.
LOF. Receiving loss of frame alarm in optical link (red): ON or flashing, when loss of frame
occurs in receiving optical link.
ERR. Local receiving bit error alarm in optical link (yellow): Flashing, when the bit error rate
exceed 10-3 in receiving optical link; steady on and refreshes every other 10~20 seconds,
when the bit error rate exceed 10-6.
V35AL. Receiving E1 signal error alarm in optical link (red): When there are AIS (Upper E1
signal line warning), LOF (G.704 frame mis-pace) or CRC (CRC4 checkout warning)
warnings from the data received at the optical port to E1 data, the indicator is on or flashing.
Please check the E1 line. When the equipment is working at E1 fractional mode, V35AL only
represents AIS indicator. .
LOOP STATE. Loop-back indicator (yellow): When the local Multiplexer is in the loop-back
state, the LOOP STATE indicator on the L line is ON. When the opposite Multiplexer is in
the loop-back state, the LOOP STATE indicator on the R line is ON.

RaisecomTechnologyCo.,Ltd. http://www.raisecom.com
- 10 -
3.1.2 Fiber Optic Interface
For the dual-strand models, the fiber optic interface is DSC/PC. TX stands for optical signal
output (transmit); RX stands for optical signal input (receive).
For the single-strand models, the fiber optic interface is SC/PC and SC/APC. Please see the model
specification.
3.13 LOOP SW loop-back setting switch
The switch has two bit, the definition is as following:
First Second Definiton
OFF OFF Normal working status（Default status）
ON OFF Remote V.35 and optical port are all loop-back
OFF ON No definition, reserved
ON ON The local V.35 and optical port can all loop
back.
zThis figure of ‘V.35 and optical port all loop back on this equipment’
At this time, the LOOP STATE indicator on the L line of the Local Multiplexer is on, at the same
time, the the LOOP STATE indicator on the R line of the Local Multiplexer is also on.
zThis figure of ‘V.35 and optical port all loop back on the remote equipment’
At this time, the LOOP STATE indicator on the R line of the Local Multiplexer is on, at the same
time, the the LOOP STATE indicator on the L line of the Local Multiplexer is also on.
Local
Multiplexer
Opposite
Multiplexer
Error code
e
q
ui
p
men
t
OFV.35
Error code
e
q
ui
p
men
t
Local
Multiplexer
Opposite
Multiplexer
Error code
e
q
ui
p
men
t
OF
V.35
Error code
e
q
ui
p
men
V.35

RaisecomTechnologyCo.,Ltd. http://www.raisecom.com
- 11 -
3.1.5 V.35 (DCE) Interface
V.35 interface adopts V.35/ISO2593: DCE Connector Face – 34-pin Female connector. It can be
connected by standard DTE cable. The definitions of the pins are as follows:
Pin Name Input/Output Pin Number
Chassis Ground — CGND - A
Signal Ground — GND - B
Receive Data (A) — RD(A) O R
Receive Data (B) — RD(B) O T
Receive Timing (A) — RCK(A) O V
Receive Timing (B) — RCK(B) O X
Send Data (A) — TD(A) I P
Send Data (B) — TD(B) I S
Send Timing (A) — TCK(A) O Y
Send Timing (B) — TCK(B) O AA
Terminal Timing (A) — SCTE(A) I U
Terminal Timing (B) — SCTE(B) I W
Request to Send — RTS I C
Clear to Send — CTS O D
Data Set Ready — DSR O E
Data Carrier Detect — DCD O F
Data Terminal Ready — DTR I H
I --- input; O --- output.
3.2 Dip-switch SW1 Setup on the Bottom Panel
Optical
interface
V.35
Interface
底视图
Set switch on the
Bottom Panel

RaisecomTechnologyCo.,Ltd. http://www.raisecom.com
- 12 -
SW1
Notice: If the configuration of the SW1 and SW2 on the bottom panel has been changed, it is
effective only after restarting! It is advised to set the switch before power on.
The dip-switch SW1 on the bottom panel has 8 bit and the definition is as following:
1st ~ 5th bit: V.35 interface bandwidth setup
6th bit: bandwidth master control/slave control setup
7th ~ 8th bit: timing resource option
3.2.1 The 1st ~ 5th Bit: V.35 Interface Bandwidth Setup
V.35 bit rate is N*64kbps (N=1~31) when working at fractional E1 mode; V.35 bit rate is
2048kbps when working at transparent E1 mode. These 5 bits of the dip-switch are actually
representing the binary code of the N value. When N is configured to 0,
RC801/803/805-30B-FV35 is working at transparent E1 mode.
1st bit 2nd bit 3rd bit 4th bit 5th bit Bandwidth (bit/s)
0 0 0 0 0 2048K (transparent E1 mode)
0 0 0 0 1 1×64K=64K (minimum bandwidth)
0 0 0 1 0 2×64K=128K
0 0 0 1 1 3×64K=192K
0 0 1 0 0 4×64K=256K
0 0 1 0 1 5×64K=320K
0 0 1 1 0 6×64K=384K
0 0 1 1 1 7×64K=448K
0 1 0 0 0 8×64K=512K
0 1 0 0 1 9×64K=576K
0 1 0 1 0 10×64K=640K
0 1 0 1 1 11×64K=704K
0 1 1 0 0 12×64K=768K
0 1 1 0 1 13×64K=832K
0 1 1 1 0 14×64K=896K
0 1 1 1 1 15×64K=960K
1 0 0 0 0 16×64K=1024K
1 0 0 0 1 17×64K=1088K
1 0 0 1 0 18×64K=1152K
1 0 0 1 1 19×64K=1216K
1 2 3 4 5 6 7 8
ON
OF 1234
SW2

RaisecomTechnologyCo.,Ltd. http://www.raisecom.com
- 13 -
1 0 1 0 0 20×64K=1280K
1 0 1 0 1 21×64K=1344K
1 0 1 1 0 22×64K=1408K
1 0 1 1 1 23×64K=1472K
1 1 0 0 0 24×64K=1536K
1 1 0 0 1 25×64K=1600K
1 1 0 1 0 26×64K=1664K
1 1 0 1 1 27×64K=1728K
1 1 1 0 0 28×64K=1792K
1 1 1 0 1 29×64K=1856K
1 1 1 1 0 30×64K=1920K (Max bandwidth 1)
1 1 1 1 1 31×64K=1984K (Max bandwidth 2)
In the above table, ‘1’ stands for OFF status of the switch, and ‘0’ stands for ON status. For
example, the binary code corresponding to 384kbps bandwidth is ‘00110’. Then, the switches shall
be set to ‘ON, ON, OFF, OFF, ON’. When doing this, users are advised to note down the binary
code corresponding to the required bandwidth, then refer to the above table for switch status.
‘Max bandwidth 1’is the maximum bandwidth in PCM30.
‘Max bandwidth 2’is the maximum bandwidth in PCM31.
3.2.2 The 6th Bit: V.35 Bandwidth Control Option
6th bit Bandwidth Control Option
OFF Master Control
ON Slave Control
The following conditions shall be satisfied in order to realize the remote bandwidth control
function.
1. RC801/803/805-30B-FV35 series modems are deployed point to point, and in pairs.
2. There is no PCM equipment (i.e. DXC, MUX) that takes up the No. 0 timeslot in the link.
3. Neither of the RC801-30B-FV35 at both sides shall be set to transparent mode (N is not 0).
When all the conditions are met, user can set Master Control at one site, and Slave Control at the
other site. The first 5 bits switches can be set to all OFF. After the link is established, the actual
bandwidth at Slave Control site is the same as the Master Control site. Please note that neither of
the both sites can be set to transparent mode (N=0).
This bit switch has nothing to do with the timing resource. Users can either set Master Control at
the Master Clock site, or at the Slave Clock site.
If any of the three conditions cannot be met, then both modems shall be set to Master Control and
the first 5 bits will be used to configure the actual bandwidth. Please note that when N=0, the
equipment is working at transparent mode and this bit switch is invalid.

RaisecomTechnologyCo.,Ltd. http://www.raisecom.com
- 14 -
3.2.3 The 7th and 8th Bits: Timing Resource Option
7th bit 8th bit Timing Resource Option
OFF OFF Master Clock (Internal)
OFF ON V.35 Terminal Clock
ON OFF Vacant
ON ON Slave Clock (follow the link clock)
Users are advised to select the most suitable timing resource according to the connection types in
Chapter 2. When configuring the timing resource, V.35 DTE interface on Routers shall also be
configured. Both TX and RX clock shall be External Clock mode at V.35 interface that connected
with Master/Slave Clock equipment. The TX Clock shall be Internal Clock mode and RX Clock
shall be External Clock mode at the V.35 interface that connected with Terminal Clock equipment.
3.2.4 The Factory Default Setup of SW1: All OFF
Switch 1st bit 2nd bit 3rd bit 4th bit 5th bit 6th bit 7th bit 8th bit
Default OFF OFF OFF OFF OFF OFF OFF OFF
Details N=31，V.35 bandwidth 1984K
Bandwidth
Master
Control
Master Clock
Mode
3.3 Dip-switch SW2 Setup on the Bottom Panel
See the position of SW2 in chapter 3.2
3.3.1 The 1st ~ 4th Bits Definition
1st bit 2nd bit 3rd bit 4th bit
Definition TX CLK
phase
RX CLK
phase
PCM30/31
Option
CRC
function
option
ON Negative Negative PCM30 Disable
1 2 3 4
SW2

RaisecomTechnologyCo.,Ltd. http://www.raisecom.com
- 15 -
OFF Positive Positive PCM31 Enable
Since the relationships between V.35 data and clock phase are different on different brand
Routers, TX CLK and RX CLK phase options are used to solve the problem. When TX CLK
and RX CLK are both set to Positive, the RC801-30B-FV35 modem has passed the test at the
V.35 synchronous WAN interface of CISCO series Routers.
TX CLK positive: TD signal will be sampled at the falling edge of TCK clock signal
TX CLK negative: TD signal will be sampled at the rising edge of TCK clock signal
RX CLK positive: RD signal will be sampled at the falling edge of RCK clock signal
RX CLK negative: RD signal will be sampled at the rising edge of RCK clock signal
PCM30/31 option. When other equipment (i.e. DXC, MUX) in the link requires the frame
format to be PCM30, the modem shall be configured to PCM30 (N≤30); when requires the
frame format to be PCM31, the modem shall be configure to PCM31 (N≤31). The local and
remote sites shall have the same configuration.
CRC option. Disable/Enable the CRC function according to the link requirement. The local
and remote sites shall have the same configuration.
3.3.2 The Factory Default Status of SW2:All OFF
Switch 1st bit 2nd bit 3rd bit 4th bit
Status OFF OFF OFF OFF
Definition TX CLK
positive
RX CLK
positive PCM31 CRC
Enable
Chapter 4. Installation and Troubleshooting
This chapter is for the reference for technical person. If it is the first time using this equipment,
please carefully read Chapter 2 and 3 first.
4.1 Cautions before Applying the Power Supply
It is strictly forbidden to hot-swap the V.35 interface cable.
If adopts the DC –48V power supply, please first connect the Protecting Ground (the middle
pin); then the 0V pin (the right pin, high electrical potential); at last the –48V pin (left pin,
low electrical potential). They must not be reversely connected.
After making sure that the cable is all right, power on.
4.2 Connection Diagnosis
ERR indicator may be ON when just after connecting the optical fiber. This is because a few error

RaisecomTechnologyCo.,Ltd. http://www.raisecom.com
- 16 -
bits are generated by connecting cables. ERR indicator shall be OFF in 10~20 seconds.
Check if there is any alarm on local equipment
Test if data communication can be performed between local DTE and remote equipment
If the test is failed, please try the following steps.
1. Local V.35 interface loop-back. Refer to previous dip-switch setup for details. If the Router
indicates loop-back successful, the V.35 interface is working in good condition. If the Router
indicates loop-back fails, please first check the timing resource and bandwidth setup at local
site, and try to adjust the TX CLK and RX CLK phase option switch.
2. After the success of the first step, check if the optical link works in good condition. If
RC801-30B-FV35 modems work in pairs (or adopts RC800-30B-FV35 at the remote site),
users are advised to perform the remote loop-back test. The local Router shall indicate if the
remote loop-back in optical link is successful.
3. If the modem is not working in pairs, it is required that the other brand equipment be
configured exactly the same as the local modem, including PCM30/31 format, CRC
enable/disable, and timing resource etc. If these parameters are properly configured, then
please pay attention to the V.35 data engrossment in frame format. Refer to Chapter 1.3.4 for
timeslot engrossment and ensure that both equipments have the same configuration.
4. After success of the second step (or ensure the 3rd step), it is indicated that the
communication link between local and remote equipments is working properly. Now, if the
remote V.35 interface is connected properly but still cannot communicate normally, please
adjust the TX CLK or RX CLK phase option on remote modem (or converter).
If the link still remains disconnected, please contact the technical support from the local
distributors. It is strongly suggested users present a report of the encountered problems along with
network topology, and the test details of the above four steps, and email the report to the technical
support.
4.3 Fault-pass-through Function
If L line alarm appears, DCD signals will be disconnected at V.35 interface, and the DTE shall
response that.
If R line alarm appears, CTS signals will be disconnected at V.35 interface, and the DTE shall
response that.
4.4 FAQs
If there is any problem during installation and operation, please try the following solutions. If the
problems still cannot be solved, please contact distributors for technical support.
Local Alarm Indicator (LAL) is ON.
Answer: It is possible that there is uplink alarm (AIS), loss of frame (LOF), or CRC alarm
appearing on the modem. It indicates that the signal received is abnormal. Please check the link
quality and interface parameter at the remote site.

RaisecomTechnologyCo.,Ltd. http://www.raisecom.com
- 17 -
Remote Alarm Indicator(RAL) is ON.
Answer: It is because there is receiving alarm at the remote site. The signal is send by the remote
interface converter RC903-V35FE1.
Optical Interface LOS is ON.
Answer: Receiving signal at optical interface is lost. Please check if the optical input (RX) is
connected, or reversely connected. Users can use the optical power meter to test the receiving
optical power to check if it is above the threshold of optical receiving sensitivity.
Optical Interface LOF is ON.
Answer: Optical receiving signal is loss of frame. Optical signals are receiving but the optical
power may be around the threshold. Please check the receiving optical power. If connects modem
of different brand name at optical interface, there also may be LLOF alarm.
Optical Interface ERR is ON.
Answer: When flashing, the bit error rate of optical signal is above 10-3. Please check if the optical
interface is connected properly, or the receiving optical power, and also ensure there is no sharp
turn of the optical fiber. When steady on, the bit error rate of optical signal is above 10-6. This
alarm may be appearing just after applying the power supply, which is normal phenomenon, and it
shall be off in 10 seconds. If the indicator is steady on during operation, please check if the optical
interface is connected properly and the receiving optical power.
Severe packet loss of DTE equipment
Answer: The possible reasons for severe packet loss are：
1．Incorrect timing resource setup
2．Check V.35 interface status of the Router, if there are data errors on input and output, then it
indicates that TX CLKand RX CLK phase relationship need to be adjusted. This problem can
be located by performing local V.35 interface loop-back test.
3．Cable loose, or line order mistake.
Compatibility with similar equipment of other brands
Answer: Raisecom RC801/803/805-30B-FV35 cannot cooperate with similar products of other
brands. It is because the signal coding and protocols at optical interface are different. However,
users can refer to Chapter 2.3 for details of extended connection types.
Compatibility with other Raisecom V.35 interface equipment
Answer: RC800-30B-FV35 can cooperate with other Raisecom V.35 interface equipments that
have similar functions, such as followings:
1. RC903-V35FE1 standalone V.35 to fractional E1 interface converter
2. RC904-V35FE1 modular V.35 to fractional E1 interface converter
3. SUBM-FV35 N*64kbps V.35 interface expansion module that installed into
RC800-240B series standalone fiber optic multiplexer.

RaisecomTechnologyCo.,Ltd. http://www.raisecom.com
- 18 -
BROADBAND
To RAISECOM
Copyright Declaration：Raisecom Technology Co., Ltd. is the owner of this manual booklet.
The part or whole of this manual is not allowed to reproduce without Raisecom’s permission.
All rights Reserved.