T1 HDSL 2-Wire Transceiver (T1HD2-XCVR)
The T1 HDSL 2-Wire Transceiver (T1HD2-XCVR) plug-in card functions as an inter-terminal transport or service card at a T1 rate. The T1HD2-XCVR card supports HDSL2 functionality and a longer reach than conventional HDSL cards, and provides improved spectral compatibility with other xDSL services (without repeaters). The T1HD2-XCVR card provides a single T1 rate interface up to 23 kft over repeatered #24 AWG copper facilities.

Features and Benefits

  • Operates as H2TU-C or H2TU-R
  • Dual flash memory banks for upgrade support
  • AMI/ZCS and B8ZS line coding
  • SF, ESF, Unframed, and Auto framing formats
  • Supports HDSL2 functionality defined in ANSI T1.418, Issue 2
  • Functions as an inter-terminal transport or service card
  • One HDSL2 T1 (1.544-Mbps) interface per card
  • Line-powering capability
  • Supports one ADTRAN range extender
  • Extensive loopback diagnostics and performance monitoring capabilities
  • Front panel jack access for test and monitoring
  • Intact asynchronous T1 delivery capability
  • Synchronous T1 delivery capability

Included Highlights

Bi-Directional Transmission

The T1HD2-XCVR card transmits and receives up to 24 DS0s of voice or data over one copper wire pair. The T1HD2-XCVR does not use separate transmit and receive pairs—it uses one pair that provide bidirectional transmission. The card can function in an unframed format to allow for intact (asynchronous) T1 delivery to subscribers using the ADTRAN HDSL2 module. It can also function in a framed format to deliver groomed T1 service.

ADTRAN Compatible HDSL2

As an inter-terminal transport, the T1HD2-XCVR links two Tellabs 1000 terminals via a T1 span. The T1HD2-XCVR inter-operates with ADTRAN-compatible HDSL2 products. The T1HD2-XCVR card only supports H2TU-R and H2TU-C from ADTRAN, and is not end-to-end interoperable with PairGain/ADC equipment.

Transport and Service

The T1HD2-XCVR card supports inter-terminal transport, intact (asynchronous) T1 service and groomed T1 service

Loopback Testing

The T1HD2-XCVR card supports extensive loopback diagnostics, including command-initiated loopbacks from the CLI when provisioned for service, inband loopbacks, Facility Data Link (FDL) loopbacks, and Loopback status of the entire HDSL2 span

Faceplate LED Indicators

The T1AX has three LED indicators on the faceplate. The green ACTV LED indicates the plug-in card is communicating with a counter part T1AX in another Tellabs 1000 terminal. The ACTV LED blinks rapidly (120 flashes per minute) during self-test and provisioning, and slowly (60 flash es per minute) during a loopback test. The red FAIL LED indicates a plug-in card failure or problem communicating with the CPU. The red FAIL LED blinks when there is illegal signaling. The red LOC LED indicates a problem receiving incoming data (LOS or high BER). The green AIS LED is reserved for future use.

Performance Enhancements

The second-generation T1HD2-XCVR card versions (0120-0151, 0120-0152) have the following additional features, such as up to 23 kft repeatered T1 transmission on #24 AWG copper facilities, up to 17 kft repeatered T1 transmission on #26 AWG copper facilities, interoperable with the T1X-XCVR card when an H2TU-C or H2TU-R is used and compatible with other standards-based HDSL2 products.


  • Width: 0.563 inch (1.429 cm)
  • Depth: 10.5 inches (26.67 cm)
  • Weight: 0.5 pound (0.23 kg)
  • Height: 5.125 inches (13.018 cm)
  • One (1) HDSL2 T1 (1.544-Mbps) interface per card
  • Typical power consumption (with sealing current): 9 W
  • Typical power consumption (span power at 62mA span load): 22 W
  • Operating temperature: -40 F / -40 C to +149 F / +65 C
  • Humidity (relative): 5 to 95% non-condensing
  • IEC 801-2
  • GR-1089-CORE (Class A2)
  • ANSI T1.418-2002.TA-NWT-1210
  • Telcordia Class AC with span power
  • FCC part 15 Class A
  • T1.418, Issue 2
  • Transmission: One pair full duplex
  • Framing: SF, ESF, Unframed, and Auto framing formats
  • Line coding: TC-PAM
  • Loopback modes: Equipment and Facility
Faceplate LED Indicators
  • FAIL Red: Plug-in card hardware failure, or the card cannot communicate with the CPU
  • ACTV Green: Card is synchronized with far end
  • ACTV Amber: Card is synchronized, but data reception is unsatisfactory (high BER, SNR under margin threshold, LOF, loop attenuation threshold exceeded, AIS, or Yellow alarm)
  • ACTV Red: 1 Card is not synchronized with far end
  • ACTV off: 2 Card is not synchronized with far end
  • LOC REM Red: Local signal reception failure (LOF, LOS,high BER, and so forth)
  • LOC REM Yellow: Remote (far end) signal reception failure
  • LBK Green: One or more T1HDx device on the span (at local, remote, or both locations) is in the Armed state
  • LBK Flashing Green: This T1HD2-XCVR card is in loopback
  • LBK Flashing Yellow: 1 At least one T1HDx device on the span (but not this card) is in loopback
  • Tellabs Panorama Element Management System (EMS)
  • Craft User Interface (CUI)
Software Support
  • Minimum base software FP16 and higher
  • Supported in Tellabs 1000 MSAP CBA1120 and CBA1048
Faceplate Jacks
  • E OUT Equipment Output: DS1 test access toward the internal cross-connect (backplane)
  • E IN Equipment Input: DS1 monitoring access from the internal cross-connect (backplane)
  • F IN Facility Input: DS1 monitoring access from the facility (line)
  • F OUT Facility Output: DS1 test access toward the facility (line)
Loop Parameters
  • Transmit power: 16.5 dBm (± 0.5 dBm)
  • Nominal input impedance: 135 Ω
  • Return loss: x > 12 dB (50 kHz to 200 kHz)
  • Span power (line powering): -190 Vdc up to 20 W maximum (one range extender)
  • Sealing current: -190 Vdc @15 mA
Range Limits (with no bridged taps)
  • #24 AWG no repeaters: 12 kft (3.7 km)
  • #24 AWG one repeater: 23 kft (7.0 km)
  • #26 AWG no repeater: 9 kft (2.7 km)
  • #26 AWG one repeater: 17 kft (5.2 km)
Compatibility with 0120-0151
  • ADTRAN H2TU-C: Part # 122X001L4, Part # 122X003L4, Part # 122X004L4 and Part # 122X007L4
  • ADTRAN H2R: Part # 1221045L1
  • ADTRAN H2TU-R: Part # 122X026L1 and Part # 122X026L2
  • ADTRAN H2TU-C: Part # 122X001L1, Part # 122X001L2, Part # 122X003L1, Part # 122X003L2, Part # 122X004L1, Part # 122X004L2, Part # 122X0045L11 and Part # 122X0045L12
  • ADTRAN H2R: Part # 1221045L1
  • ADTRAN H2TU-R: Part # 122X026L7
Compatibility with 0120-0127
  • ADTRAN T200 H2TU-R: Part # 122X.026 LX
  • ADTRAN H2TU-C: Part # 122X.001 LX, Part # 122X.0003 LX and Part # 122X.0004 LX
  • ADTRAN H2R: Part # 1221045L1 and Part # 1221045L2
Product Specifications Sheet

T1 HDSL 2-Wire Transceiver (T1HD2-XCVR)
Product Specifications
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