Listen Technologies LT-84T-01 ListenIR TAA 2-Channel Transmitter Radiator Combo

Listen Technologies LT-84T-01 is a two-channel infrared transmitter and radiator combo designed for assisted listening environments. It enables wireless infrared audio transmission for venue operators supporting accessibility and compliance workflows. This makes it ideal for classrooms, courtrooms, boardrooms, and similar spaces where reliable assistive listening coverage is critical.

The unit supports selectable carrier frequencies and dual-channel operation, allowing multiple audio sources to be transmitted within the same space. Integrated input controls and frequency selection simplify system configuration while supporting compatibility with ListenIR receivers and expansion radiators.

In real-world use, the transmitter supports consistent audio coverage across small to mid-size venues while maintaining operational stability. Its mounting flexibility and power management features support long-term installation and dependable daily operation.

Key Features

• Two-Channel Transmission: Supports dual-channel infrared audio transmission for flexible assisted listening configurations.
• Selectable Carrier Frequencies: Allows selection of multiple carrier frequencies to support system setup and expansion.
• Integrated Radiator Output: Provides power and RF signal output for compatible expansion radiators.
• Multiple Input Options: Supports microphone and line-level audio inputs for source integration.
• TAA Compliant Configuration: Manufactured in approved Trade Agreements Act countries for government procurement.

Technical Specifications

Audio
Frequency Response: 20 Hz - 20 kHz (+/- 1 dB) Line Input, 63 Hz - 15 kHz (+/- 3 dB) System Specification (wireless end-to-end with LR-4200)
Signal-to-Noise Ratio: > 70 dB (SNR) Line Input, > 60 dB (SNR) System Specification (wireless end-to-end with LR-4200)
Microphone Input: Two (2) 3.5 mm (0.14 in.) Tip/Sleeve connector, -30 dBu nominal input, +14 dB headroom, impedance 4.4k Ohms, 5 VDC bias supply
Total Harmonic Distortion: < 0.1% (THD) Line Input, < 2% (THD) System Specification (wireless end-to-end with LR-4200)
Unbalanced Line Input: Stereo/Mono Input, Two (2) Dual (RCA) Phono connectors, unbalanced, -10 dBu nominal input, +14 dB headroom, impedance 10k Ohms
Balanced Line Input: Mono Input, Two (2) Phoenix type connector, balanced, +4 dBu nominal input, +14 dB headroom, impedance 100k Ohms

Controls
Power Switch: Three (3) position switch - Power OFF, Power ON-Indicator Lights OFF, Power ON-Indicator Lights ON
Carrier Frequency Selection: Two (2), four (4) position rotary switches (2.3 MHz, 2.8 MHz, 3.3 MHz, 3.8 MHz)
Level Control Knob: Two (2) audio taper rotary potentiometer, counter-clockwise decreases input level, clockwise increases input level

Indicators
Power Supply LED: Green LED on in-line power supply indicates AC power is applied
Audio Level Indicators: Two (2) Green LEDs, two (2) Red LEDs, Green LED indicates Audio presence and Red LED indicates peaks in the audio
RJ-45 Amber LED: Solid Amber indicates carrier is present and IR is being transmitted
RJ-45 Green LED: Solid Green indicates power is applied to unit, flashing indicates unit has entered power save mode

RF
Carrier Frequencies: 2.3 MHz, 2.8 MHz, 3.3 MHz, 3.8 MHz, Selectable
Number of Channels: Two (2) channels, Selectable carrier frequency
Frequency Accuracy: +/- 0.05% stability 0 to 50 C
Transmitter Stability: 50 PPM
Modulation: FM Wideband, +/-50kHz deviation max, 50 75 pre-emphasis
Power Save Mode: Carrier will shut off when no audio is present for 15 minutes on both channels to preserve radiator life

IR
Coverage Area: 2,787 m2 (30,000 ft2) single channel with LR-4200-IR/LR-5200-IR receivers or 697 m2 (7,500 ft2) single channel with LR-42/LR-44 receivers
IR Emitter Power: 1.49 W

Power
Power Supply Input: 100-240 VAC, 50-60 Hz
Power Supply Output: 12 VDC, 4 A, 48 W
Power Supply Connector: 2.5 mm ID barrel connector, center positive
Power Output: Two (2) RJ-45 connectors, providing Power and RF signal for up to two (2) LA-141 expansion radiators on each output
Power Supply Type: In-line switching mode power supply, Listen part number LA-210
Power Supply Line Cord: IEC line cord, North America Type B (LT-84-01)

Physical
Color: Black with White Silk Screening
Unit Weight with Power Supply: 1.8 lbs. (0.8 kg)
Shipping Weight: 3.4 lbs. (1.54 kg)
Mounting: Can be mounted on a wall, ceiling, or table with provided hardware (screws and hollow wall anchors not provided). Optional LA-347 Wall Box Mounting Plate is available for mounting to a standard single gang electrical box.
Dimensions (H x W x D): 3.8 x 27.2 x 10.5 cm (1.5 x 10.7 x 4.1 in.)
Unit Weight: 0.8 lbs. (0.4 kg)

Environmental
Temperature - Operation: 14 F (-10 C) to +104 F (40 C)
Temperature - Storage: -4 F (-20 C) to +122 F (50 C)
Relative Humidity: 0 to 95% relative humidity, non-condensing

Compliance
Standards: FCC part 15, ICS-03, CE, UL, CUL, C-Tick, CCC, PSE, KC, GS, RoHS, WEEE, BIS
Power Supply Compliance Marks: CUL, UL, CE, CCC, C-Tick, KC, PSE, GS, FCC, RoHS, BIS

What’s in the Box

(1) LT-84T-01 ListenIR TAA 2-Channel Transmitter Radiator Combo
(1) Quick Start Guide
(1) Assistive Listening Notification Signage
(2) Phoenix Type Connectors
(1) Mounting Hardware
(1) Power Supply and Power Cord