Loop Simulator Handy for DSL Testing

  • 06/01/00

Aiding in schools' network and high-speed access installations, Telebyte Inc.'s Model 454 Local Loop Simulator is a compact laboratory and production test unit that precisely simulates the frequency response of the local loop used by telephone companies. It presents an accurate simulation of both the amplitude and propagation delay characteristics of a single, 26 AWG (0.4mm) telephone pair at frequencies extending from DC up to 1.5 MHz. This is the frequency range of ADSL technology, used to provide high speed Internet access over a local loop.

The unit emulates local loops extending up to a maximum of 18,500 feet. For enhanced flexibility, Model 454 is comprised of separate sections that can individually simulate the characteristics of cable lengths of 500 feet, 1,000 feet, 2,000 feet and 3,000 feet. These sections can be connected in any combination to allow simulation in 500-foot increments of any cable length up to 18,500 feet. Tandem connection is accomplished with front panel push-button switches. In addition, by employing multiple units, ADSL modems can be tested in configurations with bridge taps.

Model 454 is completely passive, requiring no AC power, which makes it a very portable tool. It is equipped with two bi-directional ports, supporting both 400 Volt levels and 120 mA DC current. Telebyte, Inc., Greenlawn, NY, (800) 835-3298, www.telebyteusa.com.

Featured

  • classroom scene with students gathered around a laptop showing a virtual tour interface

    Discovery Education Announces Spring Lineup of Free Virtual Field Trips

    This Spring, Discovery Education is collaborating with partners such as Warner Bros., DC Comics, National Science Foundation, NBA, and more to present a series of free virtual field trips for K-12 students.

  • glowing padlock shape integrated into a network of interconnected neon-blue lines and digital nodes, set against a soft, blurred geometric background

    3 in 4 Administrators Expect a Security Incident to Impact Their School This Year

    In an annual survey from education identity platform Clever, 74% of administrators admitted that they believe a security incident is likely to impact their school system in the coming year. That's up from 71% who said the same last year.

  • horizontal stack of U.S. dollar bills breaking in half

    ED Abruptly Cancels ESSER Funding Extensions

    The Department of Education has moved to close the door on COVID relief funding for schools, declaring that "extending deadlines for COVID-related grants, which are in fact taxpayer funds, years after the COVID pandemic ended is not consistent with the Department’s priorities and thus not a worthwhile exercise of its discretion."

  • pattern of icons for math and reading, including a pi symbol, calculator, and open book

    HMH Launches Personalized Path Solution

    Adaptive learning company HMH has introduced HMH Personalized Path, a K-8 ELA and math product that combines intervention curriculum, adaptive practice, and assessment for students of all achievement levels.