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🔊 Product Overview
The TOA ZM-104A is a portable impedance meter designed for measuring AC impedance in speaker lines, which cannot be measured with standard multimeters.
With simple, tester-like operation, this unit allows quick and reliable on-site inspection and troubleshooting of speaker systems—especially in PA (public address) and emergency broadcast systems.
By switching between three measurement ranges, the ZM-104A supports a wide spectrum from low to high impedance, making it suitable for various audio installations.
It also includes a handy impedance-to-power conversion chart, enabling users to easily estimate wattage from measured values.
✨ Key Features
🔍 Measures AC Impedance
Specifically designed for speaker line impedance
Not measurable with standard testers
🧰 Simple Tester-Like Operation
Easy to use in the field
Ideal for quick diagnostics and maintenance
📊 Wide Measurement Range
3 selectable ranges (×1 / ×10 / ×100)
Covers low to high impedance systems
⚡ Ideal for Audio System Maintenance
Perfect for PA systems and emergency broadcast setups
Helps identify wiring issues and faults
📘 Conversion Chart Included
Converts impedance readings into approximate wattage
Simplifies system evaluation
📊 Main Supply4 × AA batteries (DC 6V)Measurement Range×1: 5 Ω – 1 kΩ / ×10: 50 Ω – 10 kΩ / ×100: 500 Ω – 100 kΩOscillation Frequency1 kHz ±10%Accuracy±10% (approximate measurement)Continuous Use×1: approx. 30 hrs / ×10 & ×100: approx. 60 hrsDimensionsApprox. 120 × 220 × 63 mmWeightApprox. 730 g (excluding batteries & case)
📦 What's Included
Test leads
Carrying case
Impedance / power conversion chart
🎯 Ideal For
PA system installers and technicians
Maintenance of emergency broadcast systems
Audio engineers and facility managers
Troubleshooting speaker line issues

TOA ZM-104A Impedance Meter Handheld Battery Operated new
$297.49
TOA Corporation ZM-104A Impedance Meter
$248.99
TOA ZM-104A Impedance Meter, Measures Impedance of Speaker Lines Up to 100k Ohms
$285.00
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