A handheld grey field strength meter with a row of orange indicator lights, a switch, and small buttons on its front panel.

Williams Sound Proloop FSM Measurer of Induction Loops Systems

by Williams Sound

$520.00, see price history

Price is what the vendor listed when last checked. Confirm it with the vendor before buying.

Professional setup required This tool is made for professional testing of loop systems. The readings only help if the person using it knows the standard and how to set up the tests. Wrong readings can lead to a loop that is passed when it should be fixed, which wastes money and leaves listeners with poor sound. That is why a trained professional should use it.

What it is

Summary

AI-generated from vendor-published content · October 1, 2026

The Proloop FSM Plus is a handheld meter that checks how strong and clean the magnetic signal is in a hearing loop system, following the IEC 60118-4:2006 standard. It reports readings for output level, frequency response, automatic gain control, distortion, and background noise. You can also plug in headphones to listen to the loop and judge the sound by ear. This is a testing tool for installers and audiologists, not a listening device for someone with hearing loss. It runs on two AA batteries, and the headphones are not included.

Getting it

Many states lend devices like this for trial periods, free or at low cost — find your state's AT lending program.

Where to get it

Diglo Visit
$520.00

This is the vendor WhatCanHelp tracks for this product — it may also be available from other retailers or a local supplier, and prices vary.

How to fund this

These are common places to ask about paying for equipment like this. Each one decides its own eligibility and what it covers, so start by asking them.

All funding programs, state by state →

Details

Quick Facts Catalog facts · auto-generated
Type
Addresses
Platform
Age range
Complexity
Professional setup required
Price
$520.00
Funding
  • Out of pocket
  • Vocational rehab

What setup looks like

  • Out of the box
    Insert two AA batteries and switch the meter on.
  • With a guide
    Set the test ranges for field strength and background noise to match the loop being checked.
  • With professional help
    A trained installer, audiologist, or ATP should run the measurements and read the results against the IEC 60118-4 standard. Plan on 30 to 60 minutes per room.

Sources & fine print

Vendor facts (name, price, platforms, vendor link) sourced from Diglo — view on vendor site (opens in a new tab); last checked October 31, 2026.

Classification & description AI-generated from vendor-published content on October 1, 2026 · confidence: high. Vendor specs may lag; verify before relying on details in a clinical or funding artifact.

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