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User Manual
Installation and Operation
LT-84 ListenIR Transmitter/Radiator Combo
LA-141 ListenIR Expansion Radiator
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Table of Contents
Safety Cautions!.. ................................................................................................................................... 2
Recycling Instructions .......................................................................................................................... 2
Compliance Information ...................................................................................................................... 3
Compliance Notice, FCC and Industry Canada Statements ......................................................... 3
System Overview ................................................................................................................................... 4
LT-84 ListenIR Transmitter/Radiator Combo .................................................................................. 5
Package Contents ........................................................................................................................... 5
LT-84 Rear View Quick Reference ...................................................................................................... 5
LA-141 ListenIR Expansion Radiator .................................................................................................. 6
Package Contents ........................................................................................................................... 6
LA-141 Rear View Quick Reference .................................................................................................... 6
LT-84 and LA-141 Coverage .................................................................................................................. 7
Designing a System ............................................................................................................................... 9
Flexible Mounting Hardware Instructions..................................................................................... 10
Mounting Hardware Kit ............................................................................................................... 10
Mounting Provision Thread ¼” x 20 (6mm x 1.0 thread) ......................................................... 10
Wall Surface Mounting Example ................................................................................................ 11
Ceiling Surface Mounting Example ............................................................................................ 11
Mounting Two Units with Linking Mount Example .................................................................. 11
Interconnection and Control ............................................................................................................ 12
Connection of the External Power Adaptor .............................................................................. 12
Connection of External Audio Sources ...................................................................................... 13
IR Frequency Selection/Control .................................................................................................. 14
ListenIR Expansion Link RJ-45 Connections .............................................................................. 15
Indicator Lights ............................................................................................................................. 16
Troubleshooting ........................................................................................................................... 17
LT-84 Specications ..................................................................................................................... 18
LA-141 Specications ................................................................................................................... 19
Warranty Information ........................................................................................................................ 20
Technical Support Contact ................................................................................................................ 21
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Safety Cautions!
CAT-5e Cable Safety:
Do NOT Plug the LT-84 (ListenIR Transmitter/Radiator Combo) CAT-5e cable into anything other than an
LA-141 (ListenIR Expansion Radiator). The LT-84 CAT-5e Expansion Output RJ-45 connection is proprietary
and is not compatible with Ethernet or any other system. Failure to comply with this caution can damage
the LT-84, LA-141 or other equipment and will void the warranty.
Hearing Safety:
The LT-84 is designed to be used with Listen Technologies receivers. These receivers are designed to
amplify audio to a high volume level which could potentially cause hearing damage if used improperly.
To protect your hearing, make sure the volume is turned down before putting on the ear speaker or
headphones, then adjust the volume up to the minimum setting require to hear clearly. Do not allow
children or other unauthorized individuals to have access to this product without supervision.
Medical Device Safety:
Before using Listen Technologies receivers with an implantable or other medical device, consult your
implantable or other medical device physician or manufacturer. Always make sure you are using this
product in accordance with the safety guidelines established by your physician or the implantable device
manufacturer.
Recycling Instructions
Recycling:
Help Listen Technologies protect the environment by taking the time to dispose of your equipment
properly.
Product Recycling Instructions:
Please do NOT dispose of your Listen Technologies equipment in the household trash. Please
take the equipment to an electronics recycling center; OR, return the product to the factory
for proper disposal.
Battery Recycling Instructions:
Please do NOT dispose of batteries in the household trash. Please take the batteries to a
retail or community collection point for recycling.
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Compliance Information
No FCC license or radio approval is required to operate this equipment.
Compliance Notice,
FCC and Industry Canada Statements
Compliance Notice
This device complies with part 15 of the FCC Rules. Operation is subject to the following two conditions:
(1) These devices may not cause harmful interference, and (2) these devices must accept any interference
received, including interference that may cause undesirable operation.
FCC Statement
This equipment has been tested and found to comply with the limits for a class B digital device, pursuant
to part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful
interference in a residential installation. This equipment generates, uses and can radiate radio frequency
energy and if not installed and used in accordance with the instructions, may cause harmful interference
to radio communications. However, there is no guarantee that interference will not occur in a particular
installation. If this equipment does cause harmful interference to radio or television reception, which
can be determined by turning the equipment o and on, the user is encouraged to try to correct the
interference by one or more of the following measures:
• Reorient or relocate the receiving antenna.
• Increase the separation between the equipment and receiver.
• Connect the equipment into an outlet on a circuit dierent from that to which the receiver is
connected.
• Consult the dealer or an experienced radio/TV technician for help.
The user is cautioned that changes and modications made to the equipment without the approval of
manufacturer could void the user’s authority to operate this equipment.
Industry Canada Statement
This equipment complies with ICES-003 class B.
CAN ICES-3 (B)/NMB-3(B)
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System Overview
The LT-84 is an all-in-one two channel infrared (IR) transmitter and radiator (Transmitter/Radiator Combo)
packed into a single mountable enclosure. The LT-84 IR radiator is located behind the IR transparent front
panel and provides line-of-sight coverage of 30,000 ft2 (2787 m2) with LR-4200-IR/LR-5200-IR receivers or
7,500 ft2 (697 m2) with LR-42/LR-44 receivers.
The LT-84 is perfect for high-quality audio applications like assistive listening, audio description or
language interpretation in corporate boardrooms, courtrooms, training rooms, classrooms, and theaters.
Its exible audio inputs accept microphone, consumer and line level inputs which are all mixed to the
modulated IR transmission. IR receivers then detect the modulated IR transmission and convert the IR
signals back into an audio signal and presents it to headphones.
For better line of sight coverage or for coverage in larger areas the LT-84 can be combined with up to
four (4) LA-141 Listen IR Expansion Radiators. The LA-141s are connected in a daisy chain fashion to the
LT-84 via a 24 AWG unshielded CAT-5e cable. A maximum of two (2) LA-141s can be connected to each
expansion link output on the LT-84 with a maximum cable length of 100 ft. (30 m).
LT-84
Power
Power Supply
Microphone (Electret)
Unbalanced Audio Source
Balanced Audio Source
LA-141
(Optional)
LA-141
(Optional)
MIC
RCA
CAT-5e
Phoenix
Connector
LA-141
(Optional)
LA-141
(Optional)
CAT-5e
(24 AWG)
CAT-5e
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LT-84 ListenIR Transmitter/Radiator Combo
Package Contents
LT-84 ListenIR Transmitter/Radiator Combo
LA-210 12 VDC Universal Power Supply
Power Cord
LA-344 Mounting Hardware
(2) Phoenix Type Connectors
Quick Start Guide
LA-303 Small Room Signage Kit
LA-84 Stationary IR Transmitter/Radiator Combo
Power Cord
LA-210 12 VDC Universal Power Supply
Hearing Assistance Available
Asistencia auditiva a su disposición
Aide à l’audition
Mount Adaptor
This facility is equipped with a hearing assistance system.
Please ask for a receiver.
Este establecimiento está equipado con un sistema
de asistencia auditiva. Por favor solicite un receptor.
Cet éstablissement est équipé d’un système d’aide
à l’audition. S’il vous plaît demandez un récepteur.
Quick Start Guide
LA-303 Small Room Signage Kit
Mounting
Plate Cover
LT-84 Rear View Quick Reference
LT-84 Rear View
Safety/Security
Cable Slot
Mic
Input
Level Control
Knob
Frequency
Selector
Mic
Input
Level Control
Pan & Tilt
1/4” x 20
All Thread Piece
Frequency
Selector
Knob
LA-344 Mounting Hardware
2” Extension Bars
Flush Mounting Plate
Expansion Link
Amber LED
(Status Indicator)
(2) Phoenix Type
Connectors
Output RJ-45
Ceiling Tile
Mounting Plate
Pan and Tilt
Lock Screw
Hex Key
Power Input
Power Switch
Indicator Lights
On/O
RCA Input
(Stereo)
Line Input
Level
Indicators
Transmission
On/O
RCA Input
(Stereo)
Line Input
Level
Indicators
Transmission
Green LED
(Power Indicator)
On/O
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LA-141 ListenIR Expansion Radiator
Package Contents
LA-141 ListenIR Expansion Radiator
(1) 25 ft. (7.6 m) CAT-5e Cable
LA-344 Mounting Hardware
Quick Start Guide
LA-141 Listen IR Transmitter/Radiator Combo
LA-344 Mounting Hardware
Pan & Tilt
1/4” x 20
Mount Adaptor
Ceiling Tile
Mounting Plate
All Thread Piece
Mounting Plate
Cover
2” Extension Bars
Flush Mounting Plate
Hex Key
Pan and Tilt
Lock Screw
LA-141 Rear View Quick Reference
LA-141 Rear View
Safety/Security
Cable Slot
Expansion Link
In/Out RJ-45
(1) 25 ft. (7.6 m) CAT-5e Cable
Quick Start Guide
Amber LED
(Status Indicator)
PAGE 6
Indicator Lights
On/O
Channel 1
Delay
Compensation
Channel 2
Delay
Compensation
Green LED
(Power Indicator)
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LT-84 and LA-141 Coverage
The units emit a beam of infrared light from the front panel. Infrared light is not visible to the human eye.
Below is a scaled diagram of the typical line-of-sight IR pattern or “footprint” emitted from the units.
When using a unit in single channel transmit mode the coverage area is 30,000 ft2 (2787 m2) and in 2
channel transmit mode the coverage area is 15,000 ft2 (1394 m2). Use the diagrams below when evaluating
a given space to determine the number of units required and placement of those units for
best line-of-sight coverage with an LR-4200-IR or LR-5200-IR receiver.
Figure 1: LT-84 or LA-141 Single Unit Coverage Pattern “footprint” 1 & 2 Channel Transmission
Figure 2: LT-84 and LA-141 Single Channel Coverage Pattern “footprint” from same emission point
(40% increase)
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Figure 3: LT-84 and LA-141 Single Channel Coverage Pattern “footprint” Overlapping 50 ft. (15.24 m) apart
Figure 4: Single Channel Coverage Pattern “footprint” same emission point at an angle of 15 degrees o axis
Figure 5: Single Channel Coverage Pattern “footprint” same emission point at an angle of 30 degrees o axis
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Designing a System
Use the following steps when designing an IR system:
1. Determine the number of audio channels that will be used (1 or 2).
2. Determine the room size and shape.
3. Use the room size and shape information along with the appropriate 1 or 2 channel coverage
pattern footprint to overlay the footprint on the room dimensions and determine the number of
units required and the placement of those units to cover the desired listening audience.
Best performance is achieved:
• When radiators face and have direct line-of-sight to audience.
• When a system provides over-lapping coverage (like a sprinkling system).
• When special coverage is provided for shaded areas like under a balcony.
• When mounted above and angled down into the listening audience
9 – 16 ft. (2.8 - 4.9 m) high and at an angle between 10 and 30 degrees.
Examples below are provided for design concept only and do not represent the actual LT-84 coverage pattern “footprint”.
Direct Line-Of-Sight Coverage
Over-Lapping Coverage
Shaded Balcony Area
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Flexible Mounting Hardware Instructions
LT-84 & LA-141 Universal Mounting Hardware Kit
A universal mounting kit is supplied to simplify the mounting process for the LT-84 and LA-141. This kit
contains the components for mounting to a at surface wall or ceiling, attaching to a drop ceiling grid
T bar or connecting units together. Please refer to the diagram below.
Mounting Hardware Pieces
Pan & Tilt
1/4” x 20 Mount Adaptor
Ceiling Tile
Mounting Plate
All Thread Piece
Mounting Plate Cover
2” Extension Bars
Flush Mounting Plate
Hex Key
Pan and Tilt
Lock Screw
Threaded Mounting Socket ¼” x 20 (6mm x 1.0 thread)
The LT-84/LA-141 have a ¼” x 20 thread (6mm x 1.0 thread) hole located in the bottom and top of the
enclosure. This threaded hole is used to attach the units to the provided universal mounting kit or to any
user provided mounting device using a ¼” x 20 thread (6mm x 1.0 thread). Refer to the diagrams below of
ceiling and wall mounting using the universal kit provided.
1/4” x 20 Thread Mounting Hole
Top and Bottom
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Wall Surface Mounting Example
Wall Mount
Ceiling Surface Mounting Example
Ceiling Mount
Solid ceiling surface or T bar mounting
Mounting Two Units with Linking Mount Example
Linking Mount
or
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Interconnection and Control
The LT-84 is a two (2) channel IR Transmitter/Radiator. Separate input and control sections are located on
the rear panel of the LT-84 to accommodate the two (2) channel transmission. Refer to the diagram below
for location of these two separate channel control areas, power input, and expansion link output RJ-45s.
Expansion Link
Power Input
Output RJ-45
Connections and Setup
Channel 1
Connections and Setup
Channel 2
Connection of the external power adaptor
Power for the LT-84 is provided by a 12 VDC 4A universal switching power supply. The diagram below
highlights the connection point for power and the associated power switch.
Power Switch
Indicator On/O
Power Input
Barrel Connector
1. The supplied power adaptor is an in line universal switching power supply that can be used with an
AC power source from 100 – 240 VAC, 50/60Hz. The overall length of the line cord and DC power cable
is 10 ft. (3 m). Note that if the LT-84 is located further than 10 ft. (3 m) from the nearest AC outlet,
provisions will need to be made for extending the power.
2. The Power Switch ON/OFF control is a three (3) position switch located to the right of the power input
connector.
a. In the “top” position the unit is turned ON and the indicator lights are active.
b. In the “middle” position the unit is turned ON and the indicator lights are NOT active.
c. In the “bottom” position the LT-84 and LA-141 are OFF.
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Connection of External Audio Sources
Each channel has the option for three (3) audio connections. The interconnection and control of each
channel is identical. We will refer to the interconnection and control of channel 1 only. Refer to the
diagram below for connection of audio sources.
Mic
Input
RCA Input
(Stereo)
Line Input
Level Control
Knob
Level
Indicators
View of Channel 1 audio interconnections and control
1. The left side of the channel interconnection is a 3.5mm tip sleeve condenser microphone level
input. This is a -30 dBu nominal microphone level input with a 5 VDC bias supply. Any of Listen’s
microphones may be connected to this input. Note that a 3.5mm extension cable will most likely
be required when using the microphone input.
2. RCA unbalanced stereo audio input is provided through two phono connectors. These are a -10
dBu nominal level unbalanced input and the two inputs are summed together.
3. A balanced audio input is provided through the three (3) pin Phoenix type connector. This is a +4
dBu nominal level balanced input.
4. To the right of the balanced input is the audio input level adjustment control. This control rotates
clockwise to increase the audio level, counter clockwise to decrease the audio level. From the
factory this adjustment is set fully counter-clockwise.
5. A red and green LED located to the right of the level adjustment is used to determine the proper
level adjustment. With a typical audio source connected adjust the audio level adjustment up or
down until the green LED is solid green and the red LED ickers red occasionally with peaks in the
audio.
Note: LT-84 will enter Power Save Mode after 15 minutes of no audio. This state is indicated by the Green
LED (Power indicator) on the expansion link output RJ-45 ashing slowly.
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IR Frequency Selection/Control
The LT-84 provides the ability for the user to select the IR carrier frequency to be used for transmission
of the audio connected to the channel input. The carrier frequencies are at 2.3MHz, 2.8MHz, 3.3MHz, and
3.8MHz. Refer to the diagram below for selection and control of the IR carrier.
IR Frequency
Selection
IR Transmission
On/O Control
1. Located on the right side of the channel interconnection and control is the IR frequency selection. This
is a four (4) position rotary selection switch. With the switch rotated to the counter clockwise stop, the
IR frequency is set to 2.3MHz. Position 2 is 2.8MHz, position 3 is 3.3 MHz, and position 4 is 3.8MHz.
2. The IR Transmission On/O switch is used to activate the IR signal transmission for this channel. In the
“up” position the IR signal is active. In the “down” position the IR signal for this channel is NOT active.
Note: If both channels are active and set to the same frequency the LT-84 will indicate an error state and
enter Power Save Mode. Power save mode is indicated by the Green Power Indicator LEDs ashing slowly.
The error mode is indicated by 4 quick ashes on the Red Level Indicator LEDs and then turning o for 2
seconds, repeated until the error is resolved.
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Listen IR Expansion Link RJ-45 Connections
The coverage area of the LT-84 can be extended by adding up to four (4) LA-141 Expansion Radiators.
A maximum of two (2) LA-141s can be connected to each Expansion Link output RJ-45 on the LT-84 with a
maximum daisy chained CAT-5e cable length of 100 ft. (30.5 m). CAT-5e cable must be at least 24 AWG!
Refer to the diagram below.
LT-84
LT-84
Amber LED
(Status Indicator)
Green LED
(Power Indicator)
Expansion Link
Output RJ-45
LA-141
(Optional)
LA-141
(Optional)
Set Delay Compensation. For a single channel
application, set both Channel 1 and 2 Delay
Compensation switches to the same setting. For a
two channel application, set Delay Compensation
switches channel 1 and 2 independently. Pick
appropriate frequency row then move over to
the overall cable distance from the LT-84 to the
LA-141 being set, this is the switch setting.
(Optional)
(Optional)
Cable Length
1.3 MHz
2.3
2.8 MHz
3.3 MHz
3.8 MHz
Cable Length
1.3 MHz
2.3
2.8 MHz
3.3 MHz
3.8 MHz
CAT-5e
(24 AWG)
LA-141
CAT-5eCAT-5e
LA-141
Delay Compensation Switch Setting
1 to 9 ft.
0.3 to 2.8 m
50 to 59 ft.
15.2 to 18 m
0
3
3
2
3
2
2
1
10 to 19 ft.
3 to 5.8 m
3
3
3
2
60 to 69 ft.
18.3 to 21 m
3
2
2
1
20 to 29 ft.
6 to 8.8 m
3
3
2
2
70 to 79 ft.
21.3 to 24 m
3
2
1
1
30 to 39 ft.
9.1 to 11.9 m
3
3
2
2
80 to 89 ft.
24.4 to 27.1m
3
2
1
1
40 to 49 ft.
12.2 to 14.9 m
3
3
2
2
90 to 100 ft.
27.4 to 30.5
3
2
1
0
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Indicator Lights
Input Level indicators Channel 1 and Channel 2:
Green LED O and Red LED O – Low or no audio present, power
switch is o or in the indicator lights o position
Green LED solid and Red LED ashing – Audio is present and
adjusted properly on the input
Green LED O and Red LED Ch1 and Ch2 ashing quickly 4 times
with a 2 second o state, repeated – Frequency selectors are set
to the same frequency and transmission switch is active on both
channels (error state)
Level
Indicators
LT-84 RJ-45 Green and Amber LED Indicators:
Green LED OFF – Power switch is O or in the indicator lights O
position, bad power supply or not connect to AC power outlet
Green LED solid – Power is applied to the unit
Green LED ashing – Unit has entered Power Save Mode
Amber LED O – No Carrier present or problem with IR LEDs
Amber LED solid – Carrier is present and unit is actively
transmitting IR
LA-141 RJ-45 Green and Amber LED Indicators:
Green LED OFF – LT-84 power switch is O, LT-84 has entered
Power Save Mode, LA-141 indicator lights switch in O position,
bad CAT-5e cable or cable is too long
Green LED solid – Power is applied to the unit
Amber LED
(Status Indicator)
Green LED
(Power Indicator)
Expansion Link
Output RJ-45
Expansion Link
Output RJ-45
Amber LED
(Status Indicator)
Amber LED O – No Carrier present, bad CAT-5e cable or cable is
too long, problem with IR LEDs
Amber LED solid – Carrier is present and unit is actively
transmitting IR
PAGE 16
Green LED
(Power Indicator)
Page 18
Troubleshooting
The LT-84 Green LED “Power Indicators” are not lit:
• Make sure the power supply is plugged into the LT-84 and plugged into an AC outlet.
• Make sure the electrical outlet is on or if using a power strip make sure it is turned on.
• Make sure the Power Switch is set to the Indicators Lights “On” position.
• Make sure the 12 VDC in-line switching power supply is lit green and that it is working.
The LT-84’s Ch1 or Ch2 Audio “level Indicators” do not light:
• Make sure the LT-84 is plugged in.
• Make sure the Power Switch is set to the Indicator Lights “On” position.
• Make sure the audio source is active and that audio is presented to the audio input.
• Make sure the audio input is connected properly and that the level control knob is turned
clockwise.
Receivers do not pick up audio:
• Make sure the LT-84 has not entered Power Save Mode due to no active audio for 15 minutes.
• Make sure the audio source is playing and plugged into the LT-84 properly.
• Make sure the green level indicator is solid green and the red level indicator occasionally ashes
red with audio peaks.
• Make sure the receivers are operating on the same channel / frequency as the LT-84.
• Make sure the LT-84 is transmitting IR light and that the IR light is not being blocked by objects.
• If some of the receivers work but others do not, check the battery and/or earphones.
Receiver’s audio is weak and noisy:
• Make sure the green level indicator is solid green and the red level indicator occasionally ashes
red with audio peaks.
• Make sure LA-141s are connected properly and that the power and status indicator LEDs
are lit solid.
• Make sure the LT-84 and LA-141’s IR light is focused towards the listening audience.
• Make sure the receiver is directed towards the LT-84 and LA-141s.
• Make sure that all units are transmitting IR light and that the IR light is not being blocked
by objects.
• Add more LA-141s to increase the overall coverage.
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LT-84 Specifications
LT-84 Stationay IR Transmitter/Radiator Combo
Power Power Supply Type In-line switching supply, Listen part number LA-210
Power Supply Input 100-240 VAC, 50-60 Hz
Power Supply Output 12 VDC, 4A, 48W, center positive, 2.5 mm ID barrel connector
Power Line Cord North America Type B (LT-84-01), Asia and UK Type G (LT-84-02), Euro Type J (LT-84-03)
RF Carrier Frequencies 2.3 MHz, 2.8 MHz, 3.3 MHz, 3.8 MHz, selectable
Number of Channels Two (2) Channels
Modulation FM Wideband, ±50kHz deviation max, 50 μS pre-emphasis
IR Power 1.49 W
Coverage Area 30,000 ft2 (2787 m2) single channel with LR-4200-IR/LR-5200-IR receivers or 7,500 ft2
(697 m2) with LR-42/LR-44 receivers.
Expansion Link Output Two (2) RJ-45 connectors, CAT-5e cable 24 AWG, 100 ft. maximum cable length, two (2)
LA-141s per output connector
Power Save Mode Shuts o carrier when no audio is present for 15 minutes
Controls Power Switch -
Indicator Lights On/O
Level Control Knob Audio taper rotary potentiometer, counter-clockwise decreases input mix level,
Frequency Selector Four (4) position rotary switch (2.3 MHz, 2.8 MHz, 3.3 MHz, 3.8 MHz)
Transmission ON/OFF Two (2) position switch (transmission OFF, transmission ON)
Indicators Power Supply LED Green LED on in-line power supply indicates AC power is applied
Audio Level Indicators Green LED indicates Audio presence and Red LED indicates peaks in the audio
Green LEDs - Power
Indicator RJ-45
Amber LEDs - Status
Indicator RJ-45
Audio Microphone Input 3.5 mm (0.14in.) Tip/Sleeve connector, -30 dBu nominal input, +14 dB headroom,
Line Input Stereo/Mono Input. Two (2) RCA Phono connectors, unbalanced,
Line Input Mono Input. Pheonix Type connector, balanced, + 4 dBu
Frequency Response 20 Hz - 20 kHz (+/- 1 dB) Line Input
Total Harmonic
Distortion
Signal-to-Noise Ratio >70 dB (SNR) Line Input
Physical Color Black
Dimensions (H x W xD) 1.5 x 10.7 x 4.1 in. (3.81 x 27.2 x 10.5 cm)
Weight 0.8 lbs. (0.4 kg)
Unit Weight with Power
Supply
Shipping Weight 3.4 lbs. (1.54 kg)
Environmental Temperature -
Operation
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, Industry Canada, CE, RoHS, WEEE, CUL
Three (3) position switch - Power OFF, Power ON-Indicator Lights OFF, Power ONIndicator Lights ON
clockwise increases input mix level
Solid Green indicates power is applied to unit, ashing indicates unit has entered
power save mode
Solid Amber indicates carrier is present and IR is being transmitted
impedance 4.4k Ohms, 5 VDC bias supply
-10 dBu nominal input, +14 dB headroom, impedance 10k
nominal input, +14 dB headroom, impedance 100k
63 Hz - 15 kHz (+/- 3 dB) System Specication (wireless end-to-
end with LR-44)
<0.1% (THD) Line Input
<2% (THD) System Specication (wireless end-to-end with LR-44)
>60 dB (SNR) System Specication (wireless end-to-end with LR-44)
1.4 lbs. (0.7 kg)
14 °F (-10 °C) to +104 °F (40 °C)
PAGE 18
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LA-141 Specifications
LA-141 Listen IR Expansion Radiator
Power Power Supply 12 VDC, provided via LT-84 Expansion Link Output RJ-45s
Current Draw 600 mA per LA-141, maximum of two (2) LA-141s daisy chained with CAT-5e cable 24
AWG to each LT-84 Expansion Link Output
RF Carrier Frequencies 2.3 MHz, 2.8 MHz, 3.3 MHz, 3.8 MHz
Number of Channels Two (2) Channels
Modulation FM Wideband, ±50kHz deviation max, 50 μS pre-emphasis
IR Power 1.49 W
Coverage Area 30,000 ft2 (2787 m2) single channel with LR-4200-IR/LR-5200-IR receivers or 7,500 ft2
(697 m2) with LR-42/LR-44 receivers.
Expansion Link In/Out Two (2) RJ-45 connectors, CAT-5e cable 24 AWG, dasiy chain of 100 ft. maximum cable
length
Power Save Mode Shuts o carrier when no audio is present for 15 minutes
Controls Indicator Lights On/O
Switch
Indicators Green LEDs - Power
Indicator RJ-45
Amber LEDs - Status
Indicator RJ-45
Physical Color Black
Dimensions (H x W xD) 1.5 x 10.7 x 3.9 in. (3.81 x 27.2 x 10.5 cm)
Weight 0.6 lbs. (0.28 kg)
Shipping Weight 3.0 lbs. (1.4 kg)
Environmental Temperature -
Operation
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, Industry Canada, CE, RoHS, WEEE, CUL
Two (2) position switch - Indicator Lights OFF, Indicator Lights ON
Solid Green indicates power is applied to unit
Solid Amber indicates carrier is present and IR is being transmitted
14 °F (-10 °C) to +104 °F (40 °C)
PAGE 19
Page 21
Warranty Information
Listen Technologies Corporation (Listen) warrants its transmitters and receivers (LT-82, LT-700, LT-800,
LT-803, LR-100, LR-42, LR-44, LR-200, LR-300, LR-400, LR-500, LR-4200, LR-5200) to be free from defects in
workmanship and material under normal use and conditions for the useful lifetime of the product from
date of purchase.
Listen warrants it’s Listen IR Radiators (LA-140, LT-84, LA-141) to be free from defects in workmanship and
material under normal use and conditions for three years from the date of purchase.
Listen warrants its Digital IR products (T8, T16, RAD25, R8, R32) to be free from defects in workmanship
and material under normal use and conditions for two years from the date of purchase.
Listen warrants its Noise Canceling Microphone (LA-270) to be free from defects in workmanship and
material under normal use and conditions for one year from date of purchase.
Listen warrants it’s Charging/Carrying Cases (LA-306, LA-311, LA-313, LA-317, LA-318, LA-319, LA-320,
LA-321, LA-322, LA-323, LA-324, LA-325, LA-380, LA-381) to be free from defects in workmanship and
material under normal use and conditions for one year from date of purchase.
All other products and accessories are warranted for 90 days from date of purchase.
This warranty is only available to the original end purchaser of the product and cannot be transferred.
Warranty is only valid if warranty card has been returned within 90 days of purchase. This warranty is
void if damage occurred because of misuse or if the product has been repaired or modied by anyone
other than a factory authorized service technician. Warranty does not cover normal wear and tear on the
product or any other physical damage unless the damage was the result of a manufacturing defect. Listen
is not liable for consequential damages due to any failure of equipment to perform as intended.
Listen shall bear no responsibility or obligation with respect to the manner of use of any equipment sold
by it. Listen specically disclaims and negates any warranty of merchantability or tness of use of such
equipment including, without limitation, any warranty that the use of such equipment for any purpose will
comply with applicable laws and regulations. The terms of the warranty are governed by the laws of the
state of Utah.
In the rst ninety days after purchase, any defective product will be replaced with a new unit. After ninety
days, Listen will at its own discretion either repair or replace transmitters and receivers with a new unit
or a unit of similar type and condition. Product that is not covered under warranty shall be repaired or
replaced with a unit of similar type and condition based on a at fee. Contact Listen for details.
This limited warranty, prices, and the specications of products are subject to change without notice.
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Technical Support Contact
If technical service is needed, please contact Listen. Pre-authorization is required before returning
Listen products. If products were damaged in shipment, please contact the carrier, then contact Listen
for replacement or repair requirements payable by the carrier.
Listen’s corporate headquarters are located in Bludale, Utah U.S.A. and are open Monday through
Friday, 8am to 5pm Mountain Time.
LISTEN TECHNOLOGIES
14912 Heritage Crest Way
Bludale, Utah 84065-4818
+1.801.233.8992
+1.800.330.0891 North America
+1.801.233.8995 Fax
support@listentech.com
www.listentech.com
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Notes
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14912 Heritage Crest Way
Bludale, Utah 84065-4818
+1.801.233.8992
+1.800.330.0891 North America
+1.801.233.8995 Fax
support@listentech.com
www.listentech.com
© 2017 Listen Technologies Corporation® All Rights Reserved
Patented technology (pat. 9,712,246)
For further details regarding use, adjustment, or programming of your Listen products visit our website at
www.listentech.com/support-manuals or contact Listen at +1.801.233.8992 or 1.800.330.0891.
20171106
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