Spirent DLS 400 DLS 400HN ADSL Wireline Simulator Ver 11 IEEE-488 RS-232

Spirent DLS 400 DLS 400HN ADSL Wireline Simulator Ver 11 IEEE-488 RS-232

The Spirent DLS 400 is a benchtop ADSL wireline simulator used to emulate telephone loop conditions for testing ADSL modems, routers, and customer premises equipment (CPE). It allows engineers and technicians to reproduce the electrical characteristics of real subscriber loops — including loop length, loss, and bridged tap configurations — in a controlled lab environment, making it possible to evaluate ADSL device performance across a wide range of line conditions without needing access to a live telephone plant. This unit is the DLS 400HN variant, Version 11, and is part of Spirent's DLS TestWorks platform.

Specifications & What's Included

• Manufacturer: Spirent
• Model: DLS 400
• Type: DLS 400HN, Version 11
• Function: ADSL Wireline Simulator / DSL Loop Emulator
• Loop Channels: 2 — Channel A and Channel B (dual independent loop ports on front panel)
• Front Panel Indicators: POWER LED, REMOTE LED
• EXT Noise In: BNC connector, 50 Ohms (rear panel)
• LINE Connectors: Channel A and Channel B BNC ports (rear panel)
• Remote Control Interface: IEEE-488 (GPIB) — dual IEEE-488 connectors on rear panel
• IEEE-488 Address: DIP-switch configurable (set to 54321 on rear panel)
• Serial Interface: RS-232 (DCE) — DB-25 connector on rear panel
• Power Input: 100–240 VAC, 50–60 Hz, 140 VA Max
• Fuse: T2A / 250V Slow Blow
• Certifications: ENTELA Field Evaluation (CSA SPE-1000), Canadian Electrical Code Part 1, CE marked
• Country of Manufacture: Canada
• Form Factor: Benchtop enclosure (blue anodized)

Applications

The Spirent DLS 400 is used in telecom equipment development and QA labs to simulate the electrical characteristics of DSL subscriber loops. Engineers use instruments like this to test ADSL modems, DSL routers, and CPE devices against standardized loop models — including ANSI and ITU loop templates — and to verify interoperability and performance under degraded line conditions before deployment in the field. The dual-channel design allows simultaneous testing of two devices or a CO-side and CPE-side connection within the same test configuration. The IEEE-488 (GPIB) interface enables automated test integration with instruments such as network analyzers, signal generators, and test controllers running test scripts through the DLS TestWorks software platform. The DLS 400 was a widely used tool during the rapid expansion of ADSL infrastructure in the late 1990s and 2000s, when DSL equipment manufacturers and carriers needed reliable loop emulation to characterize modem performance. It remains useful today for legacy DSL testing, R&D labs, and maintenance of ADSL-era infrastructure.