Listen Technologies 700-216 LPRS assistive listening system User Manual productmanual 11x17 qrk

Listen Technologies Corporation LPRS assistive listening system productmanual 11x17 qrk

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TMUser’s Manualfor all Listen ProductsLISTENTECHNOLOGIESCORPORATION© Copyright 1999 Listen Technologies CorporationTMLISTEN TECHNOLOGIES CORPORATIONP.O. Box 683010 Park City, Utah 84068-3010 U.S.A.Shipping: 1762A Prospector Avenue Park City, UT 84060Telephone: +1.435.647.0318Toll Free: 1.800.330.0891Fax: +1.435.647.0316Internet: www.listentech.comE-Mail: info@listentech.comPrinted in U.S.A. 10/99(c) Copyright 1999 Reprint with permission only productmanual 11x17.qrk 10/11/99 2:42 PM Page 1
2LISTEN TECHNOLOGIES CORPORATION +1.435.647.0318 1.800.330.0891 Fax: +1.435.647.0316 Internet: www.listentech.com All specifications are subject to change without notice. TMLISTEN TECHNOLOGIES CORPORATION +1.435.647.0318 1.800.330.0891 Fax: +1.435.647.0316 31Internet: www.listentech.com All specifications are subject to change without notice.216MHz Frequency Compatibility Table (Continued)INTRODUCTIONAssistive Listening Systems help enhance the ability tohear in many applications. These systems deliver audiodirectly to a person’s ear through an earphone. Thisearphone can be used in conjunction with a hearing aidor placed directly on the ear. The earphone isconnected to a receiver, which picks up a broadcasttransmission of an audio source. Volume can beadjusted by the user. Audio originates from a personspeaking into a microphone or sound system.Assistive Listening Devices are commonly available infacilities such as places of worship, stadiums, arenas,meeting rooms, schools, etc. In various publicfacilities in the U.S.A., assistive listening deviceaccessibility is mandated by the Americans withDisabilities Act, and must be provided by the facility forthe hard of hearing.Listen’s FM Assistive Listening Systems, in particular,are extremely versatile, durable and easy to set up and use. 100% compatible with all major manufacturers ofFM assistive listening products, Listen products offeraccess to 57 channels at 72MHz or at 216MHz. Thismeans that if you have a Listen receiver and walk into afacility, simply press “SEEK” to find the transmittingchannel. 57 channels also more likely guarantee that afacility manager can find a clear transmission channelto broadcast on or can easily change channels ifinterference becomes a problem. Also, Listen’sreceivers and portable transmitter feature highperformance NiMH batteries which allow for hassle-free, long battery life. Another unique feature isListen’s LCD Display, which communicates batterylevel, channel and RF signal strength. Listen is dedicated to whatever-it-takes customersupport. We even offer a Limited Lifetime Warrantythat assures maximum performance and no hassle.Contact Listen; we’ll be happy to assist you.Introduction productmanual 11x17.qrk 10/11/99 2:42 PM Page 2
TMLISTEN TECHNOLOGIES CORPORATION +1.435.647.0318 1.800.330.0891 Fax: +1.435.647.0316 3Internet: www.listentech.com All specifications subject to change without notice.30 LISTEN TECHNOLOGIES CORPORATION +1.435.647.0318 1.800.330.0891 Fax: +1.435.647.0316 Internet: www.listentech.comAll specifications are subject to change without notice. 216MHz Frequency Compatibility Table Table of ContentsFrequency & Compatibility Tables72MHz . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28-29216MHz . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30-31LR-500 Programmable Display Receiverand LR-400 Display Receiver Differences in the LR-400 and LR-500 . . . . . . . . . . . .21Preparing Listen receivers for use . . . . . . . . . . . . . . .21Operating the Listen receiver . . . . . . . . . . . . . . . . . . .22Locking into only one channel . . . . . . . . . . . . . . . . . .23Receiver LED indicator . . . . . . . . . . . . . . . . . . . . . . .23Receiver battery status icon . . . . . . . . . . . . . . . . . . .23LR-400 and LR-500 Look & Listen™LCD display descriptions . . . . . . . . . . . . . . . .23Unlocking and locking the access door . . . . . . . . . . .24Charging batteries using SmartCharge™ . . . . . . . . . . .24Operating the receiver with a wall transformer . . . . .25LR-400 and LR-500 specifications . . . . . . . . . . . . . . .26Receiver troubleshooting . . . . . . . . . . . . . . . . . . . . . .27LR-500 programming . . . . . . . . . . . . . . . . . . . . . . . . .25MISCELLANEOUSTechnical Service Contacts . . . . . . . . . . . . . . . . . . . . . . . . .4Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4Compliance Notices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4Limited Lifetime Warranty . . . . . . . . . . . . . . . . . . . . . . . . . .5LT-800 Stationary TransmitterPreparing the LT-800 for use . . . . . . . . . . . . . . . . . . . . . . .6Lock into or unlock a channel . . . . . . . . . . . . . . . . . . . . . .7Audio connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7Antenna set up options . . . . . . . . . . . . . . . . . . . . . . . . . . .8LT-800 front illustration: controls & display descriptions . .9Audio controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9Operating the unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10Selecting a channel to transmit on . . . . . . . . . . . . . . . . .10LT-800 specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . .11LT-800 troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . .12LT-700 Portable TransmitterPreparing the LT-700 for use . . . . . . . . . . . . . . . . . . . . . .13Operating the unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14Selecting a channel to transmit on . . . . . . . . . . . . . . . . .15Look & Listen™ LCD display descriptions . . . . . . . . . . . .15LT-700 programming . . . . . . . . . . . . . . . . . . . . . . . . . . . .16Locking into only one channel . . . . . . . . . . . . . . . . . . . . .16LED indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16Battery status icon . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16Locking the access door . . . . . . . . . . . . . . . . . . . . . . . . .17Charging batteries using SmartCharge™ . . . . . . . . . . . . . .17Operating the unit with a wall transformer . . . . . . . . . . . .18LT-700 troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . .19LT-700 specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . .20LR-500ProgrammableDisplay ReceiverLR-400 Display Receiver productmanual 11x17.qrk 10/11/99 2:42 PM Page 3
TMLISTEN TECHNOLOGIES CORPORATION +1.435.647.0318 1.800.330.0891 Fax: +1.435.647.0316 29Internet: www.listentech.com All specifications subject to change without notice.4LISTEN TECHNOLOGIES CORPORATION +1.435.647.0318 1.800.330.0891 Fax: +1.435.647.0316 Internet: www.listentech.com All specifications are subject to change without notice. Compliance NoticesListen’s Models LT-800, LT-700, LR-400 and LR-500These devices comply with part 15 of the FCC Rules. Operation is subject to thefollowing two conditions: (1) These devices may not cause harmful interference,and (2) these devices must accept any interference received, includinginterference that may cause undesired operation.Listen’s LT-800 and LT-700 Transmitters (216MHz only)Listen’s LT-800 and LT-700 transmitters are authorized by rule under the LowPower Radio Service (47 C.F.R. Part 95) and must not cause harmful interferenceto TV reception or United States Navy SPASUR installations. You do not need anFCC license to operate these transmitters. These transmitters may only be used toprovide: auditory assistance to persons with disabilities, persons who requirelanguage translation, or persons in educational settings; health care services tothe ill; law enforcement tracking services under agreement with a lawenforcement agency; or automated maritime telecommunications system (AMTS)network control communications. Two-way voice communications and all othertypes of uses not mentioned above are expressly prohibited.Caution: Changes or modifications not expressly approved by the partyresponsible for compliance could void the user’s authority to operate Listen’sequipment.FCC StatementThis equipment has been tested and found to comply with the limits for a class Bdigital device, pursuant to part 15 of the FCC Rules. These limits are designed toprovide reasonable protection against harmful interference in a residentialinstallation. This equipment generates, uses and can radiate radio frequencyenergy and if not installed and used in accordance with the instructions, maycause harmful interference to radio communications. However, there is noguarantee that interference will not occur in a particular installation. If thisequipment does cause harmful interference to radio or television reception, whichcan be determined by turning the equipment off and on, the user is encouraged totry to correct the interference by one or more of the following measures:4 Reorient or relocate the receiving antenna.4 Increase the separation between the equipment and receiver.4 Connect the equipment into an outlet on a circuit different from that to which the receiver is connected.4 Consult the dealer or an experienced radio/TV technician for help.This equipment has been certified to comply with the limits for a class Bcomputing device, pursuant to FCC Rules. In order to maintain compliancewith FCC regulations, shielded cables must be used with this equipment.Operation with non-approved equipment or unshielded cables is likely toresult in interference to radio and TV reception. The user is cautioned thatchanges and modifications made to the equipment without the approval ofmanufacturer could void the user’s authority to operate this equipment.Technical Service Contacts & Compliance NoticesTechnical Service ContactsIf technical service is needed, please contactListen. Pre-authorization is required beforereturning Listen products. If products weredamaged in shipment, please contact the carrier,then contact Listen for replacement or repairrequirements payable by the carrier.Toll Free: 1.800.330.0891Telephone: +1.435.647.0318Fax: +1.435.647.0316Internet: www.listentech.comGeneral E-Mail: info@listentech.comShipping Address:Listen Technologies Corporation1762A Prospector AvenuePark City, UT 84068-3010 U.S.A.Correspondence Mailing Address:Listen Technologies CorporationP.O. Box 683010Park City, UT 84068-3010 U.S.A.TM72MHz Frequency Compatibility Table (continued)FCC ID Numbers:LT-800-072 (72MHz base transmitter) ID: OMD800-001LT-800-216 (216MHz base transmitter) ID: OMD800-216LT-700-072 (72MHz portable transmitter) ID: OMD700-001LT-700-216 (216MHz base transmitter) ID: OMD700-216 productmanual 11x17.qrk 10/11/99 2:42 PM Page 4
TMLISTEN TECHNOLOGIES CORPORATION +1.435.647.0318 1.800.330.0891 Fax: +1.435.647.0316 5Internet: www.listentech.com All specifications are subject to change without notice. Listen Technologies Corporation (Listen) warrants its products tobe free from defects in workmanship and material under normaluse and conditions for the useful lifetime of the product from dateof purchase. Accessories are warranted for ninety days from dateof purchase. This warranty is only available to the original endpurchaser of the product and cannot be transferred. Warranty isonly valid if warranty card has been returned within 90 days ofpurchase. This warranty is void if damage occurred because ofmisuse or if the product has been repaired or modified by anyoneother than a factory authorized service technician. Warranty doescover normal wear and tear on the product or any other physicaldamage unless the damage was the result of a manufacturingdefect. Listen is not liable for consequential damages due to anyfailure of equipment to perform as intended. Listen shall bear noresponsibility or obligation with respect to the manner of use ofany equipment sold by it. Listen specifically disclaims and negatesany warranty of merchantability or fitness of use of suchequipment including, without limitation, any warranty that the useof such equipment for any purpose will comply with applicablelaws and regulations. The terms of the warranty are governed bythe laws of the state of Utah. Listen will only accept returned products with prepaid shipping andwith a return authorization number. To receive a returnauthorization number call 1.800.330.0891 or +1.435.647.0316.Listen will refund the purchase price of the product to the originalpurchaser within the first ninety days after purchase if the productdoes not perform better than a similar competitive product subjectto an annual amount to any one original purchaser not to exceed$1,000 and subject to the conditions of this limited warranty. Thisis called our Whatever-It-takes Performance Guarantee. Refundswill only be given to the original purchaser of product once theproduct has been returned to the factory in good working orderwith an explanation for the refund. To receive a refund, call Listenfor a return authorization number. Return the product with a letteron the end user’s letterhead stating the reason for the refund and acopy of the original invoice. If the product was purchased througha dealer, refunds must be processed through the original dealer.In the first ninety days after purchase, any defective product willbe replaced with a new unit. After ninety days, Listen will, at itsown discretion either replace the unit with a new unit or a unit ofsimilar type and condition. Product that is not covered underwarranty shall be replaced with a unit of similar type and conditionbased on a flat fee.This limited lifetime warranty, prices and the specifications ofproducts are subject to change without notice.Listen Limited Lifetime WarrantyLimited Lifetime Warranty, Including Performance Guarantee28 LISTEN TECHNOLOGIES CORPORATION +1.435.647.0318 1.800.330.0891 Fax: +1.435.647.0316 Internet: www.listentech.comAll specifications are subject to change without notice. 72MHz Frequency Compatibility Table productmanual 11x17.qrk 10/11/99 2:42 PM Page 5
TMLISTEN TECHNOLOGIES CORPORATION +1.435.647.0318 1.800.330.0891 Fax: +1.435.647.0316 27Internet: www.listentech.com All specifications subject to change without notice.The LR-400/LR-500 has no power. Make sure the unit has either fully charged batteries or a Listenapproved wall transformer connected to the unit. Make surethe VOLUME knob has been rotated to the ON position. If thisdoes not work, try a different set of batteries. Make sure thebatteries are installed properly.There is no audio. Make sure you have turned the volume control up. Make surethe earphone jack is plugged all the way in to the top of unit.Make sure the transmitter is broadcasting an audio source.Make sure you're tuned to the same channel as the transmitter.If the RF signal is too weak, the receiver will squelch and thusmute the audio source; move closer to the antenna or turn upthe RF signal strength on the transmitter if possible.The audio is distorted.Make sure you're receiving on the correct channel. There is interference. Try different frequencies until you find a clear channel. If thisdoes not work, try a different frequency band (i.e. if you'reusing 72MHz, try 216MHz or vice versa). This is accomplishedby returning the equipment to Listen (at no charge).I cannot pick up the signal on the receiver. Check to make sure the receiver and the transmitter are on thesame frequency.I can pick up the signal on the receiver, but it soundslike it's not tuned in. Check to make sure the transmitter and receiver are on exactlythe same channel number/letter.I'm using another brand of transmitter - how do I tellwhich channel to use? Refer to Listen’s Frequency Compatibility Tables (included onpages 28-31). Either adjust the transmitter or the receiver to acommon channel.There is not sufficient range.Make sure you are located as close to the antenna of thetransmitter as possible. Try to locate the antenna as high aspossible and free from obstacles. It's confusing for users to have 57 channels whenswitching between channels.Use the programming feature of the LR-500 (only) to limit thenumber of channels users have access to.Users keep changing channels. You can prevent users from changing channels by pressing theSEEK button and holding it for 10 seconds. This will lock thechannel. On the LR-400, simply lock the access door to preventusers from accessing channel buttons.I cannot change channels when pressing the UP andDOWN buttons. The unit is locked. Press the SEEK button for 10 seconds tounlock.When I change channels, only certain channels areaccessible. The unit has been programmed to tune to only certain channels(LR--500 ONLY!). You can change these tunable channels by re-programming the unit.How can I limit access to the batteries? Use the side door locks. My batteries are not charging. Make sure the battery switch is in the NiMH position. Makesure you have connected an approved Listen chargingtransformer. Make sure you use ONLY NiMH batteries providedby Listen. Never try to charge alkaline or NICAD batteries. I want to run the unit from a wall transformer.Simply plug a Listen approved transformer to theCHARGE/POWER connector. Batteries need not be installed,however, NiMH will recharge if installed while the unit is beingused.Receiver TroubleshootingLR-400 and LR-500 Receiver TroubleshootingLR-400 &LR-500 RECEIVERS productmanual 11x17.qrk 10/11/99 2:42 PM Page 6
LISTEN TECHNOLOGIES CORPORATION +1.435.647.0318 1.800.330.0891 Fax: +1.435.647.0316 7Internet: www.listentech.com All specifications subject to change without notice.TMLT-800 Stationary Transmitter Controls & Audio Connections26 LISTEN TECHNOLOGIES CORPORATION +1.435.647.0318 1.800.330.0891 Fax: +1.435.647.0316 Internet: www.listentech.com All specifications are subject to change without notice. LR-500 SpecificationsRF Frequency Range:72MHz: 72.05 - 75.95MHz216MHz: 216.025 - 216.975 MHzSensitivity:.6uV typical, 1uV maximum for 12dB SINADMax deviation at ± 70kHzSignal to Noise ratio:wide band channels, 60dBnarrow band channels, 54dBFrequency Response:50Hz to 15KHz, ± 3dBDistortion:< 2% THDSquelch:40dB with loss of RF signalAntenna:Uses headphone cableAvailable Channels:72MHz: 17 wide band, 40 narrow band216MHz: 19 wide band, 38 narrow bandPhysical Dimensions:3” W x 1”D x 5”H (7.6cm W x 2.5cm D x 13cm H)Weight:< 1 lb. (.45 kg) with batteriesDoor:CHANNEL and SEEK buttons are accessible through door, lockableProgrammability:Allows only programmed channels to appear on the display, user functions can be locked by pressing the Seek button for >3 secondsPower:Two AA batteries, high capacity alkaline or NiMH rechargeable; external power connector 8-9 VDC, tip positive, <300mABattery Life:40 hours with high capacity alkaline, 20 hours with rechargeable NiMHHeadphone Output:750mV RMS maximum at 25kHz deviation, 32 ohms, 3.5MM mono or stereoLR-400 SpecificationsRF Frequency Range:72MHz: 72.05 - 75.95MHz216MHz: 216.025 - 216.975 MHzSensitivity:.6uV typical, 1uV maximum for 12dB SINADMax deviation at ± 70kHzSignal to Noise ratio:Wide band channels, 60dBNarrow band channels, 54dBFrequency Response:50Hz to 15KHz, ± 3dBDistortion:< 2% THDSquelch:40dB with loss of RF signalAntenna:Uses headphone cableAvailable Channels:72MHz: 17 wide band, 40 narrow band216MHz: 19 wide band, 38 narrow bandPhysical Dimensions:3” W x 1”D x 5”H (7.6cm W x 2.5cm D x 13cm H)Weight:< 1 lb. (.45 kg) with batteriesDoor:Channel and Seek buttons are located behind door, door can be lockedProgrammability:User functions can be locked by pressing the SEEK button for >3 secondsPower:Two AA batteries, alkaline or NiMH rechargeable; external power connector 8-9 VDC, tip positive, <300mABattery Charging:Fully automatic, <12 hoursBattery Life:40 hours with high capacity alkaline, 20 hours with high capacity NiMHHeadphone Output:750mV RMS maximum at 25kHz deviation, 32 ohms, 3.5MM mono or stereoListen Receivers: LR-500 and LR-400 SpecificationsLT-800 Transmitter LINE OUTPUT – the LINEOUTPUT connector is a mixedoutput of INPUT 1 and INPUT 2after processing. This is anunbalanced phono connector. The output level is –10dBm. INPUT 2 SWITCH: SelectLINE or SPEAKER on the slideswitch directly next to theINPUT 2 connector. In theline position, the input level is–10dBm, and on speaker, theinput level is +10dBm.INPUT 1 CONNECTION: Connect amicrophone or balanced line levelinput. See Preparation instruction#7 for details (Page 9).INPUT 1 SWITCH: Select MIC orLINE input on the slide switch. For Micinput, the level is –55dBm and theinput impedance is 50 ohms. In theline position, the input level is +4dBmand the input impedance is 600 ohms.INPUT 2 CONNECTION:this is a phono connectorused to connect anunbalanced, high imped-ance line or speaker input LT-800 Audio ConnectionsThe LT-800 has two possible audio inputs: INPUT 1 is used to connect a balanced mic or line level input. INPUT 2 is used to connect an unbalanced, high impedance line input or speaker input.Indicates RF output power(full, 1/2 or 1/4) – select on rear panelSELECTCHANNELPROCESS: Adjust the amount ofaudio processing – to make all audiosources sound like they are at thesame level, adjust clockwiseCONTOUR: Adjust voiceintelligibility equalizationfor your applicationrequirementsChannel the unitis tuned toINPUT: Adjust audio inputlevels of Inputs 1 and 2 Activates a tone toaid tuning of non-Listen receiversIndicates audioinput level of Inputs 1 and 2Shows audio levelafter processingPlug in a headset then adjust volume Power ON/OFFLT-800 Front Illustration: Controls & DisplaysTO LOCK: press both UP andDOWN buttons simultaneouslyto lock channel; press bothagain to unlockIf decimal placeis lit, channel islocked productmanual 11x17.qrk 10/11/99 2:42 PM Page 7
8LISTEN TECHNOLOGIES CORPORATION +1.435.647.0318 1.800.330.0891 Fax: +1.435.647.0316 Internet: www.listentech.com All specifications are subject to change without notice. LT-800 Stationary Transmitter PreparationTMTMLISTEN TECHNOLOGIES CORPORATION +1.435.647.0318 1.800.330.0891 Fax: +1.435.647.0316 25Internet: www.listentech.com All specifications subject to change without notice.Charging the Batteries (continued)5. Plug a wall transformer into the side of the Listen receiver orplace receiver in a Listen Battery Recharging Tray.6. Once the batteries are fully charged, the unit will stop chargingthe batteries. Full-charge will be indicated when all the batterysymbol segments are illuminated and the LED near the volumecontrol is glowing steadily.7. The unit can be operated while batteries are charging.Operating the Receiver with a Wall Transformer1. The unit will operate normally when connected to a walltransformer.2. Batteries do not need to be installed in the unit operate from awall transformer.LR-500 Receiver Programming1. The LR-500 can be programmed to operate on a limited number ofchannels. (The LR-400 cannot be programmed.) For applicationswhere users are required to select a channel (such as languagetranslation or classrooms), and you don’t want them to have to gothrough all of the available channels, this feature is ideal. If allchannels where available, the user could have 57 channels toselect from.2.3. Use the UP and DOWN keys to select channels. As channelsare displayed, the L/O symbol onthe LCD display will be displayedfor those channels that arelocked out. When a channel islocked out, the channel is notavailable to the user. To togglebetween locked out and notlocked out, press the SEEKbutton.4. To adjust squelch, the padlock iconwill appear after you program yourchannels in PROGRAM mode. Youshould still be in PROGRAM mode.To NOT adjust squelch, don’t press abutton for 4 seconds and the unit willexit PROGRAM mode. To adjustsquelch, press SEEK to unlocksquelch (the padlock will disappear).The squelch level will appear as a number of dots showing. No dotsmeans no squelch. The more dots displayed in this mode, the moresensitive squelch will be. The factory default setting is four dots.Press the UP button to rotate through the number of dots. Listen Receivers: LR-500 and LR-400, Charging (cont.) & ProgrammingTo enter PROGRAM mode, pressthe UP and DOWN keys simultane-ously until the PGM symbol isdisplayed on the LCD display.To togglebetweenlocked outand notlockedout, pressthe SEEKbutton. On each channel, check to see if“L/O” is displayed; it meanschannel is locked out from the user5. To exit PROGRAM mode, don’t press a key for 4 seconds. 4Connect Antenna: Connect the suppliedantenna according the instructions that come with theantenna. Only use an antenna supplied by Listen. Connect externalantenna here, or...Connect whip orrubber ducky antennathrough cover herePreparing the LT-800 for Use1Remove the product from the shippingcontainer and plastic cover. Inspect for physicaldamage. See "Technical Service Contacts" (Page 4) ifdamage has occurred.2For Rack Mounting: If rack mounting the unit, installthe rack mount shelf according the instructions that comewith the shelf, then install the unit and shelf in the rack.3Plug in Wall Transformer Plug the connectoron the wall transformer into the power connector onthe back panel. Use strain relief on far left side of rearpanel. Do not plug into power source yet. (Only use aListen supplied transformer.)5Set the RF POWER: Set the RF POWER switch forFULL, 1/2 or 1/4. (Level is also indicated on the frontpanel.) The amount of transmitted RF power that you willneed depends on your application. If you are operatingother transmitters in the same environment and receiverscan be used close to the antenna, it is best to have thetransmitter’s output power at its lowest level to reducethe possibility of interference.2.Press toturn powerON 3. Select channelusing UP andDOWN buttons6Power Up1.Plug transformer into outlet4. If desired, lock inselected channel bypressing both UP and DOWNbuttons simultaneouslyLock Into or Unlock A ChannelTO LOCK: Press the LT-800’s channel UP and DOWN buttonssimultaneously for three or more seconds until you see adecimal dot light up next to the channel number. To UNLOCK: Press the channel UP and DOWN buttonssimultaneously for three or more seconds until you see thedecimal dot next to the channel number disappear.LR-400 &LR-500 RECEIVERSBatteries will be fully charged when red LED shines solid red.(LED and battery symbol will flash slowly while charging.)For charging using atransformer: with NiMHbatteries in unit, plug walltransformer in CHARGINGconnection and into walloutlet (as shown). In PROGRAM mode on the LR-500,dots indicate level of squelch productmanual 11x17.qrk 10/11/99 2:43 PM Page 8
LISTEN TECHNOLOGIES CORPORATION +1.435.647.0318 1.800.330.0891 Fax: +1.435.647.0316 9Internet: www.listentech.com All specifications are subject to change without notice. TMLT-800 Stationary Transmitter Preparation & Audio ControlLT-800 Audio Control (Refer to LT-800 Controls & Displays Illustration on Page 7.)The LT-800 incorporates automatic audio level control andprocessing. Input levels can be viewed on the two VU meters on the front panel.1. ADJUST INPUT: Adjust INPUT knob counter-clockwiseto add gain to INPUT 1. Adjust INPUT knob clockwise to addgain to INPUT 2. If you have two audio sources connected toboth INPUT 1 and 2, adjust the level of one input using theVU meter, then adjust the output level of the other audiosource.2. ADJUST CONTOUR: Adjust the CONTOUR knobcounter-clockwise. If most of your audio source is voice,adjust clockwise for music. The CONTOUR knob adjusts therelative equalization of the unit. This equalization boosts orcuts frequencies above 3kHz. 3. ADJUST PROCESS: Adjust the PROCESS knobclockwise if you want more processing. This will provide foreven more consistent levels. This knob adjusts processing,relative to automatic processing already performed in theunit. The LT-800 provides dynamic audio processing intendedto keep audio levels consistent to the listener. When thePROCESS knob is rotated fully clockwise, all audio is at thesame relative level. When rotated fully counter clockwise,more dynamic range is provided for the transmitted audio source.If you’d like to disable the audio processor or make it moreaggressive, contact Listen Technical Service (Page 4).24 LISTEN TECHNOLOGIES CORPORATION +1.435.647.0318 1.800.330.0891 Fax: +1.435.647.0316 Internet: www.listentech.com All specifications are subject to change without notice. __++Top of Unit and Battery CompartmentReceiver Battery Status IconLocking the Receiver’s Access DoorCharging Batteries Using SmartCharge™1. Listen’s LR-400 and LR-500 receivers are unique because they havean automatic battery charger built in. That means that when theListen receiver is connected to a wall transformer or placed in aListen Battery Recharging Tray, NiMH batteries will be charged whilein the receiver. Once batteries are charged, the internal batterycharger will automatically turn off. This prevents overcharging ofbatteries, automates the process of charging, and makes it so youdon’t have to remember to unplug the charger.2. Do not attempt to charge alkaline or any other type of non-NiMHbatteries. Only charge Nickel Metal Hydride (NiMH) batteries withinthe LR-500 or LR-400. We recommend that you use NiMH batteriessupplied by Listen.WARNING: Attempting to charge non-NiMH batteries may result in physical harm, destruction of property and /or fire.3. IMPORTANT: To charge NiMH batteries, the BATTERY SELECTswitch must be selected to NiMH. Use a pen or small screwdriver tothe move the switch (located in the battery compartment directlybelow the BATTERY SELECT label) to the proper position.4. Install NiMH rechargeable batteries in the battery compartmentensuring that proper polarity has been observed.Listen Receivers: LR-500 and LR-400, BatteriesWhen the battery is fully charged, all three segments of the battery symbol will be displayed, as shown.As fewer battery segments are displayed, thelower the battery level, as shown.When the batteries are almost fully discharged, thebattery segments and the red LED near the volumecontrol will blink quickly. When this occurs, less than5% of the battery life is remaining and the batteriesshould be immediately replaced or recharged.To unlock: On boththe right and leftside, unlock byturning slothorizontal as shown.To lock: On both theright and left side,lock door by turningslot vertical asshown.For only NiMH batteries: setBATTERY SELECT switch toNiMH. For all other batteries, setBATTERY SELECT at alkaline.LT-800 Transmitter 9Use the headset jack to listen toaudio source – With the audio source orsources active and the unit powered ON, plug aheadset into the jack located on the LT-800’s frontpanel to listen to the audio source. Adjust headsetvolume to a comfortable level. 7Connect Audio Inputs: Connect audio source(s) toone or both audio input connections: Input 1 offers achoice of balanced XLR or 1/4” phone connection. Input 2is an unbalanced phono connector. (See LT-800 AudioConnections on Page 7 for specific connection instructions.)Balanced Input 1 connection:XLR or 1/4” phoneUnbalanced Input 2 connection:phono connectorInput 2 Switch Input 1 Switch8Adjust Audio Input Switches – For Input 1Switch, select MIC or LINE input level; Input 2 Switch,select LINE or speaker level. (See illustration on Page 7.)Connect balanced and unbalanced audio sources as shown indiagram. Make sure that if you are connecting an unbalancedaudio source, that Pin 2 of the XLR and the ring of 1/4” phonejack are connected to ground as shown.XLR Wiring 1/4” Phone WiringThe status of the batteryis indicated by the batterysymbol on the LCD. This segment will blink when batteries are low. productmanual 11x17.qrk 10/11/99 2:43 PM Page 9
Operating the LT-8001Make sure the unit is powered on.2Select a channel – Select the channel to transmit on to by pressing the channel UP and DOWN buttons. See"Selecting a Channel to Transmit On" to the right.Can’t change the channel? It may be locked. Press both theUP and DOWN buttons simultaneously for 3 seconds until thedecimal dot next to the channel turns off. Press again to lock innew channel, if desired.At 72MHz: The LT-800 at 72MHz operates on 17 wideband channels and 40 narrow band channels:Letters = Wide Band ChannelsNumbers = Narrow Band Channels At 216MHz: The LT-800 at 216MHz operates on 19 wideband channels and 38 narrow band channels:“2” as left digit = wide band channel“1” and “3” left digits = narrow band channelsPlease refer to the Frequency Compatibility Tables (Pages 28-31) forspecific frequencies and compatibility with other manufacturers.4 NOTE: Operating on a narrow band channel will have lessfidelity and more noise.3Test Tone, if necessary:To broadcast a tone, press thetest tone button. This button is used to tune other manufacturerreceivers or to identify a particular channel on a receiver.Selecting a Channel to Transmit OnSelecting a clear channel to broadcast is important for interference-free broadcasting. Wide Band Recommendation – If you don’t plan to haveother transmitters (or a limited number) operating in the same area,it is recommended that you use wide band channels. These are themost common channels used. Many people own receivers that willoperate on these channels. In addition, wide band channels offerthe best fidelity and the lowest noise. In this case, select one of the17 wide band channels A through R on 72MHz systems (19 wideband channels beginning with “2” on 216MHz systems). The bestway to select a channel is by trial and error. Try a channel, if it haslow interference and reliable performance, stick to that channel. Compatibility with other manufacturers – If you areusing other manufacturer’s receivers with the LT-800, find out theirfrequency, then refer to Listen’s Frequency Compatibility Tables(Pages 28-31) to find the LT-800 channel number or letter thatcorresponds with the receiver’s frequency. As much as possible,Listen has duplicated the wide band channel letters to coverfrequencies of other major brands. However, we recommendverifying corresponding channel numbers and letters on the tableson pages 28-31.If you are using other manufacturer’s receivers and the sound isdistorted, it is probably because the receiver is not designed tohandle the ±25kHz deviation of the Listen transmitter. This can becorrected by turning the PROCESSOR control knob all the way counter-clockwise and turning the INPUT LEVEL knob down. Or, call ListenTechnical Service (Page 4) to adjust the transmitter deviation internally. Several transmitters operating in the sameenvironment – For this, you’ll need to choose your transmittingfrequencies carefully. The following guidelines should be used tochoose channels:a. If possible, use all wide band channels. These channels offer better fidelity and lower noise. b. Select channels that have the highest frequency separation aspossible (see Frequency Compatibility Tables, pages 28-31), to avoidadjacent channels and interference. Channels should be at least200kHz apart.c. Through a process of trial and error select a combination ofchannels that offer the lowest interference and highest reliability.10 LISTEN TECHNOLOGIES CORPORATION +1.435.647.0318 1.800.330.0891 Fax: +1.435.647.0316 Internet: www.listentech.com All specifications are subject to change without notice. LT-800 Stationary Transmitter, Operation & Selecting a ChannelPress POWER button and verify powerconnections. When “ON”, display should be lit.TMLISTEN TECHNOLOGIES CORPORATION +1.435.647.0318 1.800.330.0891 Fax: +1.435.647.0316 23Internet: www.listentech.com All specifications subject to change without notice.Locking into Only One Channel Receiver LED IndicatorListen Receivers: LR-500 and LR-400, Locking & IndicatorsTo lock the receiver so userscannot change the channel, pressthe SEEK button until the LOCKsymbol is displayed. When locked, the unit will displaythe LOCK symbol.To unlock the channel, pressand hold down the SEEK buttonuntil the LOCK symbol disappearson the display.TMCHPGML/OLetters and numbers indicate the channel the unit is tuned to.Battery indicator – flashes slowing whencharging, quickly when almost dischargedWhen the LISTEN logo isdisplayed, the unit isoperating normallyIn OPERATING mode, this icon indicates thechannel is locked and cannot be changed bythe user (to lock/unlock, press the SEEK buttonuntil the LOCK symbol on the LCD display isdisplayed / not displayed). Indicates the unit is inPROGRAM mode (toenter PROGRAM mode,press UP and DOWNuntil the PGM symbolon the LCD display isshown.)In PROGRAM mode (PGMsymbol is displayed), iconindicates the channel islocked out and the user doesnot have access to thechannel.LR-400 and LR-500 Receivers: Look & Listen™Display DescriptionsSmall dots indicate the relative RF signal strength. When there is nosignal the unit is squelched and the LISTEN logo in extinguished.Steady Green LED = Proper OperationSlow Flashing = Batteryis LowSlow Flashing whenCharging = Unit isChargingLR-400 &LR-500 RECEIVERS productmanual 11x17.qrk 10/11/99 2:43 PM Page 10
TMLISTEN TECHNOLOGIES CORPORATION +1.435.647.0318 1.800.330.0891 Fax: +1.435.647.0316 11Internet: www.listentech.com All specifications subject to change without notice.RF Frequency Range:72MHz: 72.05 - 75.95MHz216MHz: 216.025 - 216.975 MHzTransmitter Stability:50 PPMFrequency Response:50Hz to 15kHz, within ±3 dbModulation Type:FM, ±25 kHz wide band, ±7.5kHz narrow bandOutput Power:72MHz: 8000uV at 3 meters216MHz: 100mW(Max allowed by FCC)Signal to Noise ratio:Wide band channels, 60dBNarrow band channels, 54dBAntenna:72MHz: Telescoping (recommended), Helical Rubber Ducky or Remote Base 216MHz: Whip, Remote Base, Ground Plane or Directional Antenna Available Channels:72MHz: 17 wide band, 40 narrow band216MHz:19 wide band, 38 narrow band(Modulation is automatically switched when changing between narrow and wide band channels)RF Power Selection:Full, 1/2, 1/4Physical Dimensions:8” W x 8”D x 1.75”H (20.3cm W x 20.3cm D x 4.45cm H)Optional rack mount kit, see Page 17Weight:3 lbs. (1.4 kg)Power:15 VAC/1 ampAudio Input 1:F-XLR / 1/4” Phone, 50/600 ohms, balanced-55dBm / +4dBm, selectable, bridgingAudio Input 2:Phono, 10k/50 ohms, unbalanced-10dBm / +20dBm, selectable, adjustableAudio Output (Mix):Phono, 10k ohms, unbalanced, -10dBmHeadphone Output:250mW, 32 ohms, 3.5MM stereoControls:Mix, Process, Contour, Headphone Level, Tone, RF Power Output, and ON/OFFVisual Indicators:Audio input levels 1, 2 and post processed modulation level; channel; RF power, test toneLT-800 Stationary Transmitter SpecificationsSpecifications subject to change without notice.LT-800 Stationary Transmitter Specifications22 LISTEN TECHNOLOGIES CORPORATION +1.435.647.0318 1.800.330.0891 Fax: +1.435.647.0316 Internet: www.listentech.com All specifications are subject to change without notice. 5Place Batteries in Unit Place two AA batteries inthe compartment, making note of the battery polarity shown inthe battery compartment, and again verifying that the BATTERYSELECT switch is switched correctly for your batteries (see Step 4).6Place an earpiece or headset in the minijack on the top of the unit. The LR-500 and LR-400 aredesigned to work with either mono or stereo connectors. NOTE: Listen receivers accept mono or stereo jacks.7Turn the receiver on by rotating the volume knobcounter-clockwise. The red LED should activate and the LCDdisplay should illuminate. If they do not, check to ensure youhave installed charged batteries and that the batteries havebeen installed with the proper polarity.Operating the Listen Receiver1Make sure the unit is on by rotating the volumeknob to ON when an earpiece or headset is plugged into theunit. Listen receivers use the cable of the earphone or headset as a receiving antenna.CAUTION: Don’t blow out your ears! Slightly rotate thevolume knob to turn the unit ON while keeping the volumeturned down. Then, adjust volume after listening to earphone.Operating Listen Receivers (continued)2Select the channel to transmit on to bypressing the UP and DOWN buttons. 4At 72MHz: Each LR-400 and LR-500 receiverat 72MHz operates on 17 wide band channels and40 narrow band channels. Letters = Wide Band ChannelsNumbers = Narrow Band Channels4At 216MHz: receivers operate on 19 wideband channels and 38 narrow bands: Channelsstarting with “2” are wide band, and channelsbeginning with “1” or “3” are narrow band channels.Please refer to the Frequency Compatibility Tables section(Pages 28-31) for specific frequencies and compatibility withother manufacturers. 4 NOTE: Operating on a narrow band channel will haveless fidelity and more noise.3Test the Audio: If a transmitter is broadcasting on thatchannel, you will be able to hear the audio. If the signal is tooweak, the audio will be muted (squelched).4Find Audio Transmission: Another way to select achannel is to press the SEEK button. When you do this, theListen receiver looks for the nextchannel that is active. Sometimesthe unit will mistake interference fora real broadcast signal. If you getinterference, simply press the SEEKbutton again. The SEEK button willalso likely stop on adjacent narrow band channels, or the wideband channel associated with the narrow band you are lookingfor. Simply continue to press SEEK until you reach the clearestoperating channel.5Adjust volume control for the best listening level.Listen Receivers: LR-500 and LR-400Turn volumeknob counter-clockwise toturn unit onLED shouldlight up solidred when unitis onLCD displayshould illuminatewhen unit is on__++Top of Unit and Battery CompartmentLT-800 Transmitter productmanual 11x17.qrk 10/11/99 2:43 PM Page 11
12 LISTEN TECHNOLOGIES CORPORATION +1.435.647.0318 1.800.330.0891 Fax: +1.435.647.0316 Internet: www.listentech.com All specifications are subject to change without notice. The LT-800 has no power. Make sure the power transformer is connected to a powersource and is connected to the jack marked "Power Input".Make sure the POWER button is pressed.There is no audio or the audio level is too low. Make sure that you have an audio source properly connected toINPUT 1 and/or 2. The INPUT 1 or 2 switch must be located inthe correct position for the appropriate input level. Forexample: if you are using the output of a mixer on INPUT 2, theswitch should be in the LINE position. If it were in theSPEAKER position, the level would be too low. Also, check theINPUT knob to ensure it is properly adjusted. You should beable to see the VU meter deflect on INPUTS 1 or 2 correspond-ing with the input level of the audio source. Try connecting aheadset to the front panel jack and adjusting the MONITORvolume control so that you can listen to the audio source.The audio is distorted. Check to make sure you have the input level select switches inthe proper position. You may be providing too much audio levelfor the input stage to handle. There is hum in the audio.Make sure you have properly grounded the audio source to the LT-800. Check the connections from the audio source to the LT-800. If you can, try to use a balanced audio source - this willreduce the chance of creating hum. Try connecting a groundfrom the LT-800 to ground and/or to the ground of the source audio.There is too much audio processing. Adjust the process knob counter-clockwise. If there is still toomuch processing for your application (or you do not want anyprocessing), contact Listen technical service.I don’t want any audio processing.Call Listen’s Technical Service (Page 4).There is a tone. The TEST TONE button has been pressed (its LED light is on).Push the TEST TONE button to turn off the tone. I cannot change the broadcast channel. The unit is locked. To unlock, press the UP and DOWN buttonsimultaneously for 3+ seconds. You can tell when it's lockedbecause the decimal is illuminated.The Audio Input 1 sounds “tinny”.If you are using an unbalanced audio source, make sure Pin 2or the XLR and the ring on the 1/4” jack is grounded.There is interference.Try different frequencies until you find a clear channel. If thisdoes not work, try a different frequency band (i.e. if you'reusing 72MHz, try 216MHz or vice versa). This is accomplishedby returning the equipment to Listen (no charge) and replacingit with Listen’s alternate frequency band equipment.I cannot pick up the signal on the receiver. Check to make sure the receiver and the transmitter are on thesame frequency.I can pick up the signal on the receiver, but itsounds like it's not tuned in. Check to make sure the transmitter and receiver are on exactlythe same channel number/letter.I'm using another brand of receiver - how do I tellwhich channel to use? Refer to Listen’s Frequency Compatibility Tables (pages 28-31).Adjust Listen’s transmitter or receiver to the same frequency asthe other major brand. Since Listen products can access 57channels, they will most likely transmit or receive on the samefixed channel or channels of other major ALD brands.There is not sufficient range.First make sure that the receivers you are using are operatingproperly. Then, make sure that you have an antenna connectedeither to the top of the LT-800 transmitter or connected to theback of the unit (but not both!). Locate the antenna at alocation as high as possible and free of obstacles. Make surethe antenna is of the correct type and is connected properly tothe unit. Try using different frequencies that don't haveinterference. If you're using 216MHz, you might want to try adirectional antenna.End users are adjusting the unit. First, lock the channel by pressing the UP and DOWN buttonstogether for 3+ seconds. Consider removing the INPUT,PROCESS AND CONTOUR knobs. You can order from Listen arack mount shelf and security cover that will limit access tounit from end users.Other manufacturers’ receivers sound distorted.It is probably because the Listen transmitter is over-deviated.See Page 10 for instructions on how to correct this.LT-800 Stationary Transmitter TroubleshootingLT-800 Troubleshooting Listen Receivers: LR-500 Programmable Display Receiver and LR-400 Display ReceiverDifferences in the LR-400 and LR-500Differences between the LR-500 and LR-400 include: SEEK andchannel UP and DOWN buttons are behind the door on the LR-400versus protruding through the door on the LR-500. Also, the LR-500 isprogrammable. See page 25 for LR-500 programming features. (Otherthan these differences, instructions for use of Listen’s LR-400 and LR-500 receivers and their specifications are identical.)Preparing Listen Receivers for Use1Remove the product from the shippingcontainer and plastic cover. Inspect for physicaldamage. See "Technical Service Contacts” (Page 4) ifdamage has occurred.2Check to see if the door is locked. If locked,use a pocketknife or small screwdriver to unlock the doorlocks on the both sides of the unit. To unlock the door, rotatethe lock 1/4 turn counter clockwise.3Open the front access door by gripping the twotabs with your thumb and index finger. 4Select Battery Type – CAUTION: If you are usingany battery type other than rechargeable Nickel MetalHydride (NiMH) batteries, make sure the BATTERY SELECTswitch is in the alkaline position (located in the batterycompartment and labeled BATTERY SELECT, remove batteriesto access this switch). The product is shipped from thefactory in the alkaline position. To use NiMH batteries, before placing in unit, changethe battery switch to NiMH. WARNING: Do not place the BATTERY SELECT switch in theNiMH position when using Non-Nickel Metal Hydridebatteries. The NiMH position will attempt to charge thebatteries. Charging non-Nickel Metal Hydride batteries mayresult in physical harm, destruction of property and/or fire. TMLISTEN TECHNOLOGIES CORPORATION +1.435.647.0318 1.800.330.0891 Fax: +1.435.647.0316 21Internet: www.listentech.com All specifications subject to change without notice.Listen Receivers: LR-500 and LR-400, Preparing for UseThe LR-400has channelUP, DOWN andSEEK buttonsbehind thedoor.The LR-500has channelUP, DOWNand SEEKbuttonsprotrudingthrough thedoor.To unlock door: Onboth the right andleft side, unlock byturning slothorizontal as shown.BATTERY SELECTSwitch - Withbatteries removed,use a pen or smallscrewdriver to selectthe battery typeLR-400 &LR-500 RECEIVERS productmanual 11x17.qrk 10/11/99 2:43 PM Page 12
TMLISTEN TECHNOLOGIES CORPORATION +1.435.647.0318 1.800.330.0891 Fax: +1.435.647.0316 13Internet: www.listentech.com All specifications subject to change without notice.Preparing the LT-700 for Use1Remove the product from the shippingcontainer and plastic cover. Inspect for physicaldamage. See "Technical Service Contacts” (Page 4) ifdamage has occurred.2Check to see if the door is locked. If locked,use a pocketknife or small screwdriver to unlock the doorlocks on the both sides of the unit. To unlock the door, rotatethe lock 1/4 turn counter clockwise.3Open the front access door by gripping the twotabs with your thumb and index finger. 4Select Battery Type – CAUTION: If you are usingany battery type other than rechargeable Nickel Metal Hydride(NiMH) batteries, make sure the BATTERY SELECT switch is inthe alkaline position (located in the battery compartment andlabeled BATTERY SELECT, remove batteries to access thisswitch). The product is shipped from the factory in thealkaline position. To use NiMH batteries, before placing in unit, changethe battery switch to NiMH. WARNING: Do not place the BATTERY SELECT switch in theNiMH position when using Non-Nickel Metal Hydride batteries.The NiMH position will attempt to charge the batteries.Charging non-Nickel Metal Hydride batteries may result inphysical harm, destruction of property and/or fire.5Place Batteries in Unit Place two AA batteries inthe compartment, making note of the battery polarity shown inthe battery compartment, and again verifying that theBATTERY SELECT switch is switched correctly for yourbatteries (see Step 4).LT-700 Portable Transmitter PreparationOn both the rightand left side,unlock by turningslot horizontal asshown.__++Top of Unit and Battery CompartmentBATTERY SELECTSwitch - Withbatteries removed,use a pen or smallscrewdriver to selectthe battery type20 LISTEN TECHNOLOGIES CORPORATION +1.435.647.0318 1.800.330.0891 Fax: +1.435.647.0316 Internet: www.listentech.com All specifications are subject to change without notice. LT-700 Portable Transmitter SpecificationsRF Frequency Range:72MHz: 72.05 - 75.95MHz216MHz: 216.025 - 216.975 MHzTransmitter Stability:50 PPMModulation Type:FM, ±25 kHz wide band, ±7.5kHz narrow bandFrequency Response:15Hz to 50kHz, within ±3dBOutput Power:72MHz: 8000uV at 3 meters216MHz: 20mW(Max allowed by FCC)Signal to Noise ratio:Wide band channels, 60dBNarrow band channels, 54dBAntenna:Uses microphone cableAvailable Channels:72MHz: 17 wide band, 40 narrow band216MHz: 19 wide band. 38 narrow band(Modulation is automatically switched when changing between narrow and wide band channels)Physical Dimensions:3”W x 1”D x 5”H (7.6cm W x 2.5cm D x 13cm H)Weight:< 1 lb. (0.45 kg) with batteriesDoor:Channel and ON/OFF buttons are accessible through the door, lockableProgrammability:Allows only programmed channels to be tuned and to be displayedPower:Two AA batteries, alkaline or NiMH rechargeable; external power connector 8-9 VDC, center positive, <300mABattery Charging:Fully automatic, < 14 hoursPhantom Power:Included for microphoneBattery Life:16 hours with high capacity alkaline8 hours with rechargeable NiMHMicrophone Input:-55dBm, 50 ohms, unbalanced, tip of 3.5MMconnectorLine Input:-10dBm, 10k ohms, unbalanced, ring of 3.5MM connectorAudio Processing:40dB automatic 3-speed dynamic controlwith noise gateControls:On/Off/Program/Lockout, Channel UP, Channel DOWN, Battery TypeMute Control:Located on top of unit, LED flashes when mute is activatedLCD:Channel, Battery/Charge Status, Program, Locked, Channel Lock OutLED:Red, Constant = ON and/or charged, fast flash = muted, slow flash = battery low or chargingLT-700 Portable Transmitter SpecificationsLT-700 Transmitter productmanual 11x17.qrk 10/11/99 2:43 PM Page 13
14 LISTEN TECHNOLOGIES CORPORATION +1.435.647.0318 1.800.330.0891 Fax: +1.435.647.0316 Internet: www.listentech.com All specifications are subject to change without notice. LT-700 Portable Transmitter Preparation (cont.), OperationPreparing the LT-700 for Use (continued)6Connect the microphone to the microphone jackon the top of the unit. The unit uses the microphone cable asan antenna. If you are using the line input, use the specialcable accessory designed for this purpose.Or, connect optional Line Level InputCable – Use an optional Listen supplied line input cable,or connect as follows:7Turn the unit on. If it does not turn on by pressingpower button, check to ensure you have installed chargedbatteries and that the batteries have been installed with theproper polarity.Operating the LT-700 Transmitter1Make sure the unit is on by opening the accessdoor and pressing the POWER button.2Select the channel to transmit on by pressing andholding the channel UP and DOWN buttons for 3 seconds. TheLOCK symbol on the LCD will go off and the channel can bechanged. Also see “Selecting a Channel to Transmit On”.Operating the LT-700: Select a Channel (continued)4At 72MHz, the LT-700 operates on 17 wideband channels and 40 narrow band channels(letters = wide band and numbers = narrowband channels). 4At 216MHz, the LT-700 operates on 19wide band channels and 38 narrow bandchannels (channels beginning with “2” = wideband, and channels beginning with “1” or “3”= narrow band channels).Please refer to the Frequency CompatibilityTables (Pages 28-31) for specific frequenciesand compatibility with other manufacturers. 4 NOTE: Operating on a narrow band channel will haveless fidelity and more noise.3Close the access door. If you choose, lock the door by rotating thelocks on the right side 1/4 turn clockwise,and on the left side 1/4 turn counterclockwise. This can be done with a smallscrewdriver or pocketknife.1. Turn POWER onby pressingbutton, turn offby pressingagain2.LED should light upgreen when ON3. LCD displayshould showbattery level,channel andthe ListenlogoAccess DoorClosedOn both the rightand left side, lockdoor by turning slotvertical as shown.TMLISTEN TECHNOLOGIES CORPORATION +1.435.647.0318 1.800.330.0891 Fax: +1.435.647.0316 19Internet: www.listentech.com All specifications subject to change without notice.The LT-700 has no power. Make sure the unit has either fully charged batteries or a Listenapproved wall transformer connected to the unit. Open thedoor and press the ON button. If this does not work, try adifferent set of batteries. Make sure the batteries are installedproperly.There is no audio.Make sure the MUTE switch is off. Make sure you have themicrophone plugged all the way in the top of unit. Make sureyou are using a Listen approved microphone. If you're usingthe line input, make sure you have connected a line level,unbalanced input to the "ring" of the connector.The audio is distorted. Make sure you're using an approved Listen microphone. Makesure the line input level is not too high. There is hum in the audio. The microphone may be too close to a transformer.The microphone is low in level.The microphone must be placed in close proximity to theperson speaking. If this does not work, try using a head-wornmicrophone.There is too much noise.This is probably due to the fact that the microphone is not closeenough to the person speaking and is picking up backgroundnoise. Try positioning the microphone closer or try using amicrophone that is directional (like a head-worn mic).There is interference. Try different frequencies until you find a clear channel. If thisdoes not work, try a different frequency band (i.e. if you'reusing 72MHz, try 216MHz or vice versa). This is accomplishedby returning the equipment to Listen (no charge) and replacedwith alternate frequency band equipment.I cannot pick up the signal on the receiver.Check to make sure the receiver and the transmitter are on thesame frequency.I can pick up the signal on the receiver, but it soundslike it's not tuned in. Check to make sure the transmitter and receiver are on exactlythe same channel number/letter.I'm using another brand of receiver - how do I tell whichchannel to use? Refer to Listen’s Frequency Compatibility Table (included onPages 28-31). Either adjust the transmitter or the receiver to acommon channel.There is not sufficient range. The LT-700 is a portable transmitter that uses the microphonecable as an antenna and as such, the range will vary dependingon the location of the receivers compared to the transmitter.You can only expect 100 feet of effective working area.It's confusing for users to have 57 channels whenswitching between channels. Use the programming feature of the LT-700 to limit the numberof channels users have access to.How can I limit access to the batteries? Use the side door locks.My batteries are not charging.Make sure the battery switch is in the NiMH position. Makesure you have turned the unit’s POWER on initially to charge.Make sure you have connected an approved Listen chargingtransformer. Or if inserted in charging tray, make sure the unitis ON and is pushed securely into tray. Make sure you useONLY NiMH batteries provided by Listen. Never try to chargealkaline or NICAD batteries. I want to run the unit from a wall transformer.Simply plug a Listen approved transformer to the Charge/Powerconnectors. Batteries need not be installed, however NiMH willbe recharged if installed, and if the BATTERY SELECT switch isset to NiMH.LT-700 Portable Transmitter TroubleshootingLT-700 TroubleshootingLT-700 Transmitter productmanual 11x17.qrk 10/11/99 2:43 PM Page 14
TMLISTEN TECHNOLOGIES CORPORATION +1.435.647.0318 1.800.330.0891 Fax: +1.435.647.0316 15Internet: www.listentech.com All specifications subject to change without notice.LT-700 Portable Transmitter, Selecting a ChannelSelecting a Channel Transmit OnSelecting a clear channel to broadcast is important for interferencefree broadcasting. Wide Band Recommendation: If you don’t plan to have othertransmitters (or a limited number) operating in the same area, it isrecommended that you use wide band channels. These are the mostcommon channels used. Many people own receivers that willoperate on these channels. In addition, wide band channels offer thebest fidelity and the lowest noise. In this case, select one of the 17wide band channels A through R on the 72MHz system, or one of the19 wide band channels on the 216MHz system labeled 2A, 2B, 2C,etc. The best way to select a channel is by trial and error. Try achannel, if it has low interference and reliable performance, stick tothat channel.Compatibility with other manufacturers – If you areusing other manufacturer’s receivers with the LT-700, find out theirfrequency, then refer to Listen’s Frequency Compatibility Tables(Pages 28-31) to find the LT-700 channel number or letter thatcorresponds with the receiver’s frequency. As much as possible,Listen has duplicated the wide band channel letters to coverfrequencies of other major brands. However, we recommendverifying corresponding channel numbers and letters on the tables onpages 28-31.If you are using other manufacturer’s receivers and the sound isdistorted, it is probably because the receiver is not designed to handlethe ±25kHz deviation of the Listen transmitter. This can be correctedby turning the PROCESSOR control knob all the way counter-clockwiseand turning the INPUT LEVEL knob down. Or, contact Listen TechnicalService (Page 4) to adjust the transmitter deviation internally. Several transmitters operating in the sameenvironment – For this, you will need to choose your transmittingfrequencies carefully. The following guidelines should be used tochoose channels:a. If possible, use all wide band channels. These channels offer better fidelity and lower noise. b. Select channels that have the highest frequency separation aspossible (see Frequency Compatibility Tables, pages 28-31), toavoid adjacent channels and interference. Selected channelsshould be at least 200kHz apart.c. Through a process of trial and error select a combination ofchannels that offer the lowest interference and highest reliability.Channel the unit is tuned toIndicates battery level in 3 stages,flashes when battery is low along withflashing red LEDIndicates the unit is in PROGRAMmode (to enter PROGRAM mode, pressUP and DOWN until the PGM symbolon the LCD display is shown.)L/O = Locked Out – while inPROGRAM mode, L/O shows whatchannels are locked in or outLT-700 Look & Listen™Display Descriptions18 LISTEN TECHNOLOGIES CORPORATION +1.435.647.0318 1.800.330.0891 Fax: +1.435.647.0316 Internet: www.listentech.com All specifications are subject to change without notice. LT-700 Portable Transmitter, Battery RechargingCharging the Batteries (continued)4. Install NiMH rechargeable batteries in the batterycompartment, ensuring that proper polarity has been observed.Note: It is recommended that you only use a Listen chargingtransformer. Or, set the LT-700 with NiMH batteries within unitand powered ON in a Listen Battery Charging Tray.5. The LT-700 must be powered ON initially tocharge NiMH batteries within unit – Connect the walltransformer to the LT-700. The unit must be on to charge.However, once the charger has started, the unit can be turned off.6. Once the batteries are fully charged, the unit will stop chargingthe batteries. Full-charge will be indicated when all the batterysymbol segments are illuminated and the LED near the volumecontrol is glowing steadily.7. The unit can be operated while batteries are charging.__++Top of Unit and Battery CompartmentFor charging using a transformer: with NiMH batteries in unit,plug wall transformer in CHARGING connection and into wall outlet(as shown). Batteries will be fully charged when red LED shinessolid red. (LED and battery symbol will flash slowly while charging.)Operating the LT-700 with a WallTransformer1. The unit will operate normally when connected to a walltransformer.2. Batteries do not need to be installed in the unit to operateusing a wall transformer.LT-700 Transmitter Indicates unit islocked into channel,press and hold UP orDOWN button for 3seconds to unlock productmanual 11x17.qrk 10/11/99 2:43 PM Page 15
TMLISTEN TECHNOLOGIES CORPORATION +1.435.647.0318 1.800.330.0891 Fax: +1.435.647.0316 17Internet: www.listentech.com All specifications subject to change without notice.16 LISTEN TECHNOLOGIES CORPORATION +1.435.647.0318 1.800.330.0891 Fax: +1.435.647.0316 Internet: www.listentech.com All specifications are subject to change without notice. LT-700 ProgrammingIn General: The LT-700 can be programmed to transmit on a limitednumber of channels. For applications where users are required toselect a channel (such as classrooms), and you don’t want them tohave to scroll through all of the available channels, this feature is ideal.If all channels where available, the user could have 57 channels toselect from.1. Enter PROGRAM Mode:2. Scroll through channels to lock or unlock Use the UP and DOWNchannel select keys to scrollthrough all 57 channels.When checking a particularchannel, the L/O symbol onthe LCD will be displayedwhen that channel is lockedout. “Locked Out” meansthe channel is not available to the user after theprogrammer exits PROGRAM mode. Locking into One Channel Enter PROGRAM Mode (as described to the right), lock allchannels except the channel you want to use. LED IndicatorBattery Status IconLT-700 Portable Transmitter ProgrammingSteady Red LED = Normal OperationSlow Flashing = Battery is LowSlow Flashing while charging = Unit is ChargingFast Flashing = MuteTo enter PROGRAM mode, openthe access door and press the UPand DOWN keys simultaneouslyuntil the PGM symbol is displayedon the LCD display.To togglebetweenlocked out andnot locked out,press thePOWER button. On each channel, check to see if“L/O” is displayed; it meanschannel is locked out from the user3. To exit PROGRAM mode, don’t press a key for 4 seconds. When the battery is fully charged, all three segments of the battery symbol will be displayed, as shown.The status of thebattery isindicated by thebattery symbol onthe LCD. As fewer battery segments are displayed, thelower the battery level, as shown.When the batteries are almost fully discharged, thebattery segments and the red LED near the volumecontrol will blink quickly. When this occurs, less than5% of the battery life is remaining and the batteriesshould be immediately replaced or recharged.This segment will blink when batteries are low.TMLT-700 Portable TransmitterUnlocking and Locking the Access DoorThe front access door can be locked so that the users will not haveaccess to controls or batteries. To do this, use a pocketknife or smallscrewdriver to rotate the locks as shown.Charging Batteries Using SmartCharge™1. The LT-700 is unique because it has an automatic batterycharger built in. That means that when the unit is connected toa wall transformer or placed in a Listen battery recharging tray,NiMH batteries will be charged within the LT-700. Oncebatteries are charged the internal battery charger willautomatically turn off. This prevents overcharging of batteries,automates the process of charging, and makes it so you don’thave to remember to unplug the charger.2. Do not attempt to charge alkaline or any other type of non-NiMHbatteries. Only charge Nickel Metal Hydride (NiMH) batterieswithin the LT-700. We recommend that you use NiMH batteriessupplied by Listen.WARNING: Attempting to charge non-NiMH batteries mayresult in physical harm, destruction of property and /or fire.3. IMPORTANT: To charge NiMH batteries, the BATTERYSELECT switch must be selected to NiMH. Use a pen or smallscrewdriver to the move the switch (located in the batterycompartment directly below the BATTERY SELECT label) to theproper position.To unlock: On boththe right and leftside, unlock byturning slothorizontal as shown.To lock: On both theright and left side,lock door by turningslot vertical asshown.For only NiMH batteries: setBATTERY SELECT switch toNiMH. For all other batteries,set BATTERY SELECT atalkaline.(Continued...)LT-700 Transmitter productmanual 11x17.qrk 10/11/99 2:43 PM Page 16

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