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Troubleshooting and Repair
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Loopback
Loopback is used to verify and locate the source of either a cable or
a synchronization problem through the devices in a T1 transmission
path. Devices in the T1 transmission path (PBX, CSU, Channel
bank, smart jacks, etc.) will generally have some type of loopback
mode. Loopback modes will typically have the effect of taking the
input T1 stream and transmitting the stream back to the source; the
nodes thereby verify that portion of the link.
In the absence of a loopback mode, the T1 transmits and receives
pairs that can be directly connected together to physically create a
loopback condition.
A&B bits
Taken from each of the 24 Channels to emulate the various analog
trunk signalling conditions (off-hook, on-hook, disconnect
supervision, etc.) in either of the two following methods.
Superframe:
Over a cycle of twelve frames, bits A&B are taken in
frames 6 & 12 to provide basic analog trunk emulation over the T1
facility.
Extended superframe (ESF):
ESF is not supported by the SX-200
EL/ML or the
SX-200 LIGHT. ESF is supported by an ISDN.
Refer to
Содержание SX-200 EL
Страница 1: ...TECHNICIAN S HANDBOOK LIGHTWARE 19 RELEASE 3 0 ...
Страница 11: ...Chapter 1 Introduction ...
Страница 12: ......
Страница 32: ...Technician s Handbook 22 ...
Страница 33: ...Chapter 2 Routine Maintenance ...
Страница 34: ......
Страница 55: ...Chapter 3 Troubleshooting and Repair ...
Страница 56: ...Technician s Handbook 46 ...
Страница 88: ...Technician s Handbook 78 Figure 16 E M Trunk Type I 2 wire ...
Страница 110: ...Technician s Handbook 100 ...
Страница 111: ...Chapter 4 Programming ...
Страница 112: ......
Страница 168: ...Technician s Handbook 158 ...
Страница 169: ...Chapter 5 Installation ...
Страница 170: ......
Страница 175: ...Installation 165 Installation SX 200 ML FD Cabinet Card Assignment Figure 24 SX 200 ML FD Cabinet Card Assignment ...
Страница 176: ...Technician s Handbook 166 SX 200 LIGHT Cabinet Card Assignment Figure 25 SX 200 LIGHT Cabinet Card Assignment ...
Страница 239: ...Chapter 6 Maintenance Commands ...
Страница 240: ......
Страница 258: ...Technician s Handbook 248 ...
Страница 261: ...Notes ...
Страница 262: ...Technician s Handbook Notes ...