Appendix B - Functional Operation; Timing; Ground Fault Detect; H2Tu-C-388 List 1 Block Diagram - ADC HiGain H2TU-C-388 User Manual

Appendix B - Functional Operation

A
PPENDIX
ADC HDSL2 technology provides full-duplex services at standard DS1 rates over copper wires between an
H2TU-C and an H2TU-R, which comprise one HiGain system. HiGain systems use ADC Overlapped PAM
Transmission with Interlocking Spectra (OPTIS) transceiver systems to establish full-duplex, 1.552 kbps data
channels between the H2TU-C-388 List 1 and a remotely located H2TU-R.
Figure 30 shows a block diagram of the H2TU-C-388 List 1. The H2TU-C-388 List 1 receives a 1.544 Mbps
DSX-1 data stream from the DSX-1 digital cross connect interface. The H2TU-C-388 contains a DS1 frame
synchronizer controlled by an 8-bit microprocessor that determines the type of framing on the DS1 stream and
synchronizes to it. The H2TU-C-388 recognizes Superframe (SF), including D4, or Extended Superframe (ESF)
framing.
Ring
110
DSX-1 IN
109
Tip
Frame GND
Tip1
114
DSX-1 OUT
115
Ring1
104 Management Bus
A
Fuse alarm 117
-48Vdc
217
POWER
B
SUPPLY
GND 218, 118
T
IMING
The low loop wander (0.5 UI max) of an H2TU-C-388, when used with a compatible remote unit, allows the
circuit to be used in all critical timing applications, including those that are used to transport Stratum 1 timing.
G F
ROUND AULT
The H2TU-C-388 has a Ground Fault Detect (GFD) circuit which detects a ground or a resistive path to ground
on any wire of the HDSL2 loop. This makes the product compliant with the Class A2 requirements of GR-1089.
52
B - F
UNCTIONAL
T1
119
FRAMER
PRE-
EQUALIZER
SELECT
MICROPROCESSOR
MODE
SEL
Figure 30. H2TU-C-388 List 1 Block Diagram
D
ETECT
O
PERATION
HDSL2
Framer
A
B
-185Vdc HDSL
Power Supply
(Ground Isolated
and Ground Fault
LEDs
RS-232
(front panel)
June 6, 2000
152-388-100-02, Issue 2
HDSL 1
XCVR
+
LineVoltage
_
Detect)
H2TU-C-388 List 1
Tip 1
101
HDSL 2
SPAN
102
Ring 1