User manual

Beijing Raisecom Science & Technology Co., Ltd. http://www.raisecom.com
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Remote loop-back: Remote equipment realizes bidirectional loop-back. Fiber optical interface of
remote equipment realizes loop-back for local equipment, and V.35 interface of remote equipment
realizes loop-back for DTE side.
As the above figure, the 5
th
bit is switched to ON, and the 6
th
bit is switched to OFF. If the optical
fiber is connected properly, the loop-back status can be viewed at the port of local and remote
Router.
3.3.2 The 7
th
and 8
th
Bits: Vacant
These two bits are vacant and reserved for further use.
3.3.3 The Factory Default Status of SW2: All OFF
Switch 1
st
bit 2
nd
bit 3
rd
bit 4
th
bit 5
th
bit 6
th
bit 7
th
bit 8
th
bit
Status
OFF OFF OFF OFF OFF OFF OFF OFF
Definition
TX CLK
positive
RX CLK
positive
PCM31
CRC
Enable
Not
loop-back
Remote
loop-back
Vacant
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 3 first.
4.1 Cautions before Applying the Power Supply
 It is strictly forbidden to hot-swap the V.35 interface cable.
4.2 Connection Diagnosis
ALM indicator may be ON when just after connecting the optical fiber. This is because a few error
bits are generated by connecting cables. ALM indicators 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.