Listen Tech LT-84 ListenIR 2-Channel Transmitter/Radiator Combo
The LT-84 ListenIR 2-channel transmitter-radiator (Pat. 9,712,246) from Listen Technologies provides venues, businesses, government agencies, and more with an affordable and easy-to-use assistive listening solution. The LT-84 is also the first infrared assistive listening system to feature expansion radiators (LA-141), which provide delay compensation to ensure that there are no signal cancellation dropouts. Up to four (4) expansion radiators (LA-141) can be added to the system to offer additional coverage (when mounted within 30.48 m <100 ft.> from the unit).
Key Features
- Affordable, effective, and expandable solution ideal for small to mid-size spaces such as classrooms, courtrooms, boardrooms, and more
- Multiple frequency options offer additional flexibility and simplicity during installation and setup
- Offers gapless coverage up to 2,787 square meters (30,000 square feet)
- Can be expanded with up to four (4) LA-141 expansion radiators for additional coverage area
- One-cable design utilizes a single CAT-5e to carry both power and signal to LA-141 expansion radiators
- Multiple input options for easier setup and operation
Technical Specifications
Audio
Frequency Response
20 Hz – 20 kHz (+/- 1 dB) Line Input63 Hz – 15 kHz (+/- 3 dB) System Specification (wireless end-to-end with LR-44)
Signal-to-Noise Ratio
> 70 dB (SNR) Line Input> 60 dB (SNR) System Specification (wireless end-to-end with LR-44)
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-44)
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 dBunominal 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 mix level, clockwise increases input mix 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
+/- .005% stability 0 to 50 C
Transmitter Stability
50 PPM
Modulation
FM Wideband, -50kHz deviation max, 50 S pre-emphasis
Power Save Mode
Carrier will shut off when no audio is present for 15 minutes on both channels to preserve radiator life
Expansion Link Output
Two (2) RJ-45 connectors – Provides RF Signal and Power, CAT-5e cable 24 AWG, 100 ft. maximum cable length, two (2) LA-141s per output connector
IR
Coverage Area
2,787 m (30,000 ft) single channel with LR-4200-IR/LR-5200-IR receivers or 697 m (7,500 ft) 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), Asia and UK Type G (LT-84-02), Euro Type C (LT-84-03), Australia Type I (LT-84-04)
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)
1.5 x 10.7 x 4.1 in. (3.81 x 27.2 x 10.5 cm)
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
Power Supply Compliance Marks
CUL, UL, CE, CCC, C-Tick, KC, PSE, GS, FCC, RoHS
