Listen LT-700 User manual

User’s Manual
LT-700 Portable Transmitter
Don’t miss a single sound. Listen.
Listen Technologies Corporation
8535 South 700 West, Suite A
Sandy, Utah 84070-2515 USA
Telephone: [phone]
Toll Free (North America): 1.800.330.0891
Fax: [phone]
E-mail: [e-mail]
Listen®and the Listen logo are registered trademarks of Listen Technologies Corporation

Welcome to Listen!
i
Dear Valued Customer,
Thank you for choosing Listen! All of us at Listen are dedicated to providing you
the highest quality products and prompt, efficient customer care. Our products are
manufactured in an ISO-9000 factory that has been independently certified to the
highest quality standards. We stand ready to answer any questions you might have
during installation or in the operation of our products. Should there be any
problems with your Listen products, we are ready to help you in any way we can.
Should you have any comments on how we might improve our products or our
service, we’re here to listen. Here’s how to reach us:
Telephone: [phone]
Fax: [phone]
Toll Free (North America): 1.800.330.0891
E-Mail: [e-mail]
Web: www.ListenTech.com
Thank you... and enjoy your listening experience!
Best regards,
The Listen Team
Listen™ and the Listen Logo are registered trademarks of Listen Technologies Corporation.
LT-700_2004_02_18 © 2004 Listen Technologies Corporation. All Rights Reserved.

Welcome to Listen!
ii
· LT-700-072 (72MHz or 216MHz)
· Warranty Card
· User Manual
LT-700 Package Contents
72 MHz: LT-700-072
216 MHz: LT-700-216
Listen Part Number
See pages 32-33.
Optional Accessories

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Table of Contents
1
Architectural Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
Quick Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Setup Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Operating Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
Programming Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Charging Batteries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Operation with a Wall Transformer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Supplementary Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
Channel Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
Listen SQ™ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
RF Reception Maximization Strategies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
72 MHz Frequency Compatibility Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
216 MHz Frequency Compatibility Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
Compliance Notice . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
FCC Statement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
Optional Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
Table of Contents

Specifications
2
Specifications
Architectural Specifications
The portable FM transmitter shall be capable of broadcasting on 57 channels. The unit shall incorporate a microphone
sensitivity switch. The device shall broadcast on both wide and narrow band channels with a SNR of 80dB or greater.
The device shall have an audio frequency response of 50Hz to 15kHz, ±3dB at 72MHz, or of 50Hz to 10kHz, ±3dB at
216MHz. The device will incorporate a mute switch. The battery door shall be capable of being mechanically locked.
The device shall incorporate an LCD display that indicates channel, battery level, low battery, battery charging, channel
lock ,program mode, channel lock status and RF signal strength. The portable transmitter shall incorporate automatic
battery charging circuitry for recharging of NiMH batteries. The Listen LT-700 is specified.
Specifications
Specification LT-700-072 LT-700-216
RF Frequency Range 72.025 - 75.975 MHz 216.025 - 216.987 MHz
Number of Channels 57 (17 wide, 40 narrow) 57 (19 wide, 38 narrow)
Sensitivity
Frequency Accuracy
Transmitter Stability
Transmission Range
Output Power Less than 10mW Less than 100mW
Antenna
Antenna Connector
Compliance
.6uV typical, 1 uV maximum for 12dB SINAD
RF
±.005% stability 0° to 50°C (32° to 122° F)
50 PPM
FCC Part 15, Industry Canada
3.5mm connector
From 0ft to 50ft(15.2m) -150 ft (45.7m)
Uses microphone cable
continued on next page

Specifications
3
Specifications continued
System Frequency Response 63Hz - 15kHz (± 3dB) 63Hz - 10kHz (±3dB)
System Signal to Noise Ratio
(A-weighted)
SQ enabled: 80dB; SQ disabled 60dB SQ enabled: 80dB; SQ disabled 50dB
System Distortion
Microphone Input
Microphone Sensitivity
Line Input
Phantom Power
Set-up Controls, behind the door
User Controls
Programming
LED
LCD Display
Battery Type
Battery Life (Listen batteries)
Battery Charging (NiMH only)
Power Supply Connector
Compliance
Dimensions
Unit Weight
Unit Weight with batteries
Shipping Weight
Door
Temperature - Operation
Temperature - Storage
Humidity
3VDC
Physical
Environmental
Audio
Indicators
Controls
Power
Unbalanced, tip of 3.5mm connector, (55 dBu nominal,
-32dBu maximum, impedance 21 Ohms)
Unbalanced, ring of 3.5mm connector, (-10dB nominal input level adjustable, +4dBu maximum,
impedance 10k Ohms)
** All system specifications are wireless end-to-end
0 to 95% relative humidity, non-condensing
5.8 oz (164.4g)
1.0 lbs (0.45kg)
Manually lockable. UP, DOWN and power through door,
other controls behind door (see Controls above)
-20° to 50°C (-4° to 122° F)
-10° to 40°C (14° to 104° F)
Two AA batteries, alkaline or NiMH
Mic sensitivity, NiMH/alkaline battery, SQ enable/disable
Unit can be programmed so that only desired channels are displayed to the user; channel selection can
be locked by holding the UP or DOWN button 5 seconds.
Power, mute, channel UP and DOWN
3.9oz (111g)
Three position switch: high, middle and low; 6dB increments
<2% total harmonic distortion (THD) at 80% deviation
2.3mm OD by 0.7mm ID, barrel type connector. 7.5VDC, center positive 300mA. Drop in contact points
for use with Listen charging cases.
UL Listed
3.0 in x 1.0 in x 5 in WxDxH (7.6cm x 2.5cm x 13.cm)
Fully automatic, 14 hours
20 hours alkaline (LA-361), 10 hours NiMH rechargeable (LA-362)
Red, illuminates when unit is on. Flashes when batteries are low,
or to indicate charging. Flashes 2x when muted
Channel, lock status, programming
Specification LT-700-072 LT-700-216

Quick Reference
4
Quick Reference
LT-700 Front
3.5mm Input Jack
A Listen microphone or line
level cable connects here.
MUTE / TALK switch
(more information on page 5)
Power Switch
Press PWR switch to turn unit
on. Press and hold to turn
unit off. When in PROGRAM
mode, this switch is used to
toggle the lock out (L/O)
mode for a channel.
Press and hold both buttons for 5 seconds to enter PROGRAM
mode. The PGM icon will appear in the display. To exit PROGRAM,
let unit sit idle for 5 seconds.
Use UP and DOWN buttons to select a channel.
Press and hold either button for 5 seconds to
lock the channel. Press and hold either button
again to unlock.
Look & Listen Display™
The display shows level, channel,
battery status, PROGRAM mode,
whether a channel is locked, and
whether a channel is locked out
from selection (PROGRAM mode).
See close-up on page 6.

Quick Reference
5
Quick Reference
LT-700 Inside Access Door
Mic Sensitivity Switch - it arrives set at MID, which will
work for most microphones. If your mic level is too low,
change the switch to HI; if the level is too high, switch to
LO. (see page 8 for more information)
Battery Select Switch - place in NiMH position ONLY if you
are using Nickel Metal Hydride batteries, otherwise, leave it
in the Alkaline position.
SQ Switch: shipped in the ON position, use a screwdriver
or pen to slide to the OFF position if needed. You should
turn SQ off if you are using any non Listen receiver or older
Listen receiver that does not have the SQ feature. (see
page 20 for more information)
Mic Sensitivity
Switch SQ Switch
Battery Select
Switch
3.5mm Input Jack
A microphone or line level cable connects here.
LED indicators:
Steady Red: Normal operation
Slow Flashing: Battery is low
Slow Flashing while charging: Unit is charging
Fast Flashing: Mute
MUTE / TALK switch - this mutes the mic
only and not the line input when in the mute
position.
LT-700 Top of Unit
A Note on Charging NiMH Batteries
If you are using NiMH batteries in any Listen
product, you should allow adequate time
for the charger (charging case or LA-202)
to complete a full charge cycle on the
batteries. This takes about 13 hours.

Quick Reference
6
Quick Reference
LT-700 Look & Listen™ Display
When dots are illuminated, the microphone
is active. If this display does not appear,
the microphone is muted.
Indicates the currently
tuned channel
Indicates the unit is in PROGRAM mode
(see next page). To enter PROGRAM
mode, press and hold the UP and DOWN
keys until the PGM icon appears in the dis-
play. To exit PROGRAM mode, let the unit
sit idle for 5 seconds. If the padlock icon is visible, the channel is
locked. Press and hold either the UP and
DOWN button for 5 seconds to lock or
unlock.
When in the PROGRAM mode, L/O
indicates whether a particular channel
is locked out.
Battery level indicator. The indi-
cator flashes, along with the red
LED on top of the unit, to alert
you when the battery is low and
needs to be charged or
changed. (see information
below)
All three segments showing:
The batteries are at 50% or
greater capacity.
One segment showing:
Your batteries less than 25% capacity. When
this segment begins flashing along with the
LED on top of the unit, you should immedi-
ately change your batteries or recharge them
(if using NiMH batteries).
Two segments showing:
The batteries are at 25-49%
capacity.
LT-700 Battery Indicator