XL2 Analyzer0 pages

A pp l i c at i o n N ot e

AFILS
Induction Loop Systems with XL2 Analyzer
This application note describes the commissioning and verification of Inductive Loop Systems according the international
standard IEC 60118-4.
Contents:
•tIntroduction
•tEquipment and Set Up
•tCalibration
•tTechnical Standards
•tMeasuring the Background Noise Level
•tMeasuring the Field Strength
•tMeasuring the Frequency Response
•tChecking the Noise Level with the Loop System
•tChecking Interference from other Loop Systems
•tSystem Check
•tInformation and a List of possible System Problems
General

Exel Line: Minirator MR-PRO with
XL2 Audio and Acoustic Analyzer

Audio-frequency induction loop systems (AFILS) improve the
speech intelligibility for hearing aid users. The acoustic measured
by a microphone are converted into a magnetic field, which will be
transformed by the T-coil in the hearing aid for the user.
This minimizes listening problems of sound sources at a distance,
with persons speaking behind protective windows and in environments with background noise. Vocal communication with a person
wearing a hearing aid is often rather poor since acoustical noise
and reverberation tend to mask the perceived signal. Wearing a
hearing aid deprives the person of directional hearing. Communication is much easier at shorter acoustic distances.
An inductive loop system enables hearing aid users to understand
the spoken messages.

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Dec 10, Page 1 / 9