Adtran TSU 600 T1/FT1 CSU/DSU Multiplexer V.35 12-Port 4-Module 1202.076L2

Adtran TSU 600 T1/FT1 CSU/DSU Multiplexer V.35 12-Port 4-Module 1202.076L2

The Adtran TSU 600 is a modular T1/FT1 access multiplexer with an integrated CSU/DSU, designed to aggregate and manage T1 and fractional T1 WAN connections across multiple service types from a single chassis. This unit (P/N 1202.076L2) is equipped with six expansion slots and has four modules installed, providing one synchronous V.35 DTE data port and twelve analog FXS voice ports. The front panel LCD shows "SYSTEM SELF-TEST / TEST(S) PASSED," confirming the unit powered on and completed its internal self-test.

Specifications & What's Included

• Model: Adtran TSU 600 (TSU-600)
• Part Number: 1202.076L2
• Network Interface: T1 / Fractional T1 (FT1), 1.544 Mbps
• Network Connector: RJ-48C
• Total Expansion Slots: 6
• Modules Installed: 4 (2 slots vacant)
• Module 1 — NX56/64 (P/N 1202.054L1): Single synchronous V.35 DTE interface × 1
• Module 2, 3, 4 — QUAD FXS (P/N 1200.300L1): Quad analog voice (FXS) module × 3
• Total FXS Voice Ports: 12 (4 ports per QUAD FXS module × 3 modules)
• Total V.35 DTE Ports: 1
• Modules are hot-replaceable
• Management: 10BASE-T Ethernet port; Control/Chain IN/OUT for daisy-chaining
• Front Panel: 2-line LCD display, keypad, multi-column LED status indicators
• Network/Alarm Jacks: IN, OUT, MON (monitor), NETWORK on rear panel
• Certifications: UL Listed (E130853), FCC Part 68 (HDCUSA-31802-DE-N), FCC Part 15, ICES-003 Canada
• Manufactured by Adtran, Huntsville, AL, USA
• Includes: Chassis with 4 installed modules — no cables or accessories included

Applications

The Adtran TSU 600 belongs to Adtran's Total Service Unit (TSU) product family, a line of T1/FT1 access multiplexers widely deployed at customer premises (CPE) in the 1990s and early 2000s for consolidating mixed voice and data traffic over a single T1 WAN circuit. The TSU 600's modular design allows a mix of data interface modules (such as the NX56/64 for synchronous V.35 connections to routers or DSUs) and voice modules (such as the QUAD FXS for connecting analog phones, fax machines, or PBX line-side ports) in one chassis, eliminating the need for separate channel banks. This made the TSU 600 a cost-effective CPE solution for small to mid-size businesses, branch offices, and campus sites needing to share a T1 across both voice and data services — a common architecture in pre-VoIP enterprise and telecom environments. The unit is still sought after for legacy T1 network maintenance, lab testing, and as a replacement unit for existing TSU 600 deployments.