INSTRUCTION MANUAL LMb Synthesized UHF Belt-Pack Transmitter Featuring Digital Hybrid Wireless® Technology US Patent 7,225,135 Quick Start Steps 1) Install good batteries and turn power on (see pages 6 and 7). 2) Set compatibility mode to match the receiver (see page 9). 3) Connect signal source and adjust input gain for optimum modulation level (see page 9). 4) Set StepSize and frequency to match receiver (see page 10). Also see receiver manual for scanning procedure.
LMb Table of Contents Introduction.............................................................................3 About Digital Hybrid Wireless ...............................................3 Frequency Agility...................................................................3 Wide-Band Deviation ............................................................3 Servo Bias Input and Wiring .................................................3 LMb Block Diagram ......................................................
Digital Hybrid Wireless Belt-Pack Transmitter Introduction The design of the LMb transmitter delivers the advanced technology and features of Digital Hybrid Wireless® in a Lectrosonics belt-pack transmitter at a modest cost. Digital Hybrid Wireless® combines a 24-bit digital audio chain with an analog FM radio link to eliminate a compandor and its artifacts, yet preserve the extended operating range and noise rejection of the finest analog wireless systems.
LMb DSP-controlled Input Limiter Pilot Tone Squelch The transmitter employs a digitally-controlled analog audio limiter prior to the analog-to-digital converter. The limiter has a range greater than 30 dB for excellent overload protection. A dual release envelope makes the limiter acoustically transparent while maintaining low distortion. It can be thought of as two limiters in series, connected as a fast attack and release limiter followed by a slow attack and release limiter.
Digital Hybrid Wireless Belt-Pack Transmitter Battery Installation The transmitter is powered by two AA batteries. We recommend using alkaline, lithium, or rechargeable batteries for longest life. Standard zinc-carbon batteries marked “heavy-duty” or “long-lasting” are not adequate. The battery status circuitry compensates for the difference in voltage drop between alkaline and lithium batteries across their usable life, so it’s important to select the correct battery type in the menu.
LMb Operating Instructions 614.4 - 691.1 MHz IR Sync Port FCCID:DBZLMBC1 S/N XXXXX Lectrosonics, Inc. Model: LMBC1 Made in U.S.A. IC: 8024A-LMBC1 RF Indicator Battery Status LED Battery icon Reserved for Future Use Input Jack 5A Power/Function LED Menu navigation buttons Modulation LEDs BAT Programmable Switch Power Button Belt clip mounting hole Move switch toward the white dot to turn it on -10 Slide door outward to open battery door -20 0 -20 -20 -10 -40 BAT 623.
Digital Hybrid Wireless Belt-Pack Transmitter Powering On in Standby Mode Locking/Unlocking Changes to Settings A brief press of the Power Button , releasing it before the counter has reached 3, will turn the unit on with the RF output turned off. In this Standby Mode the menus can be browsed to make settings and adjustments without the risk of interfering with other wireless systems nearby. RF indicator blinks Hold for Rf On ...
LMb Selecting Programmable Switch Functions The programmable switch on the top panel can be configured using the menu to provide several functions: s Power - turns the power on and off s Mute - mutes the audio when switched on s TalkBk (talkback) - redirects the audio to a different output channel on the receiver (with receivers that offer this function) Changing the step size never changes the frequency. It only changes the way the user interface works.
Digital Hybrid Wireless Belt-Pack Transmitter IR (infrared) Sync Connecting the Signal Source The opening on the side panel is an IR port for quick setup using a receiver with this function available. IR Sync will transfer the settings for frequency, step size and compatibility mode from the receiver to the transmitter. Refer to your receiver manual for details. IR Port Adjusting the Input Gain 614.4 - 691.1 MHz FCCID:DBZLMBC1 S/N XXXXX Lectrosonics, Inc. Model: LMBC1 Made in U.S.A.
LMb Selecting Step Size This menu item allows frequencies to be selected in either 100 kHz or 25 kHz increments. Compat StepSiz Phase Locked StepSiz 100 kHz 25 kHz StepSiz 100 kHz 25 kHz A fraction will appear next to the hex code in the setup screen and in the main window when the frequency ends in .025, .050 or .075 MHz. Freq. b 19 51 1 4 b 19 51 41 MUTE 494.525 Fraction appears next to hex code in 25 kHz mode 494.525 If the desired frequency ends in .025, .050 or .
Digital Hybrid Wireless Belt-Pack Transmitter About Overlapping Frequency Blocks When two frequency blocks overlap, it is possible to select the same frequency at the upper end of one and the lower end of the other. While the frequency will be the same, the pilot tones will be different, as indicated by the hex codes that appear. In the following examples, the frequency is set to 494.500 MHz, but one is in block 470 and the other in block 19.
LMb 5-Pin Input Jack Wiring The wiring diagrams included in this section represent the basic wiring necessary for the most common types of microphones and other audio inputs. Some microphones may require extra jumpers or a slight variation on the diagrams shown. Audio input jack wiring: PIN 1 Shield (ground) for positive biased electret lavaliere microphones. Shield (ground) for dynamic microphones and line level inputs.
Digital Hybrid Wireless Belt-Pack Transmitter Microphone Cable Termination for Non-Lectrosonics Microphones TA5F Connector Assembly Mic Cord Stripping Instructions 1 4 5 2 3 VIEW FROM SOLDER SIDE OF PINS 0.15" 0.3" Crimping to Shield and Insulation Strip and position the cable so that the clamp can be crimped to contact both the mic cable shield and the insulation. The shield contact reduces noise with some microphones and the insulation clamp increases ruggedness.
LMb Input Jack Wiring for Different Sources In addition to the microphone and line level wiring illustrated below, Lectrosonics makes a number of cables and adapters for other situations such as connecting musical instruments (guitars, bass guitars, etc.) to the transmitter. Visit www.lectrosonics.com and click on Accessories, or download the master catalog. A lot of information regarding microphone wiring is also available in the FAQ section of the web site at: www.lectrosonics.
Digital Hybrid Wireless Belt-Pack Transmitter Microphone RF Bypassing Line Level Signals When used on a wireless transmitter, the microphone element is in the proximity of the RF coming from the transmitter. The nature of electret microphones makes them sensitive to RF, which can cause problems with microphone/transmitter compatibility.
LMb Accessories BCSLEBN Wire belt clip M152/5P Lavaliere microphone; omnidirectional MI33PRA Instrument cable; passive type for use with very high output pickups; right angle 1/4” plug MI33PST Instrument cable; passive type for us with very high output pickups; straight 1/4” plug MI39ARA Instrument cable; active type for use with most instrument pickups; right angle 1/4” plug MI39AST Instrument cable; active type for use with most instrument pickups; straight 1/4” plug MC35 Line level adapter
Digital Hybrid Wireless Belt-Pack Transmitter Troubleshooting It is important that you follow these steps in the sequence listed. Symptom: Possible Cause: Transmitter Battery LED off when Power Switch “ON” 1. Batteries are inserted incorrectly. 2. Batteries are low or dead. No Transmitter Modulation LEDs when Signal Should be Present 1. 2. 3. 4. 5. 6. Receiver Indicates RF But No Audio 1. Audio source or cable connected to transmitter is defective. Try using an alternate source or cable. 2.
LMb Specifications and Features Operating Frequencies: Block A1: 470.100 - 537.575 Block B1: 537.600 - 614.375 Block C1: 614.400 - 691.175 Block D1: 691.200 - 767.975 (export only) Frequency Selection Steps: Selectable; 100 kHz or 25 kHz RF Power output: 50 mW Pilot tone: 25 to 32 kHz; 5 kHz deviation (Digital Hybrid mode) Frequency Stability: ± 0.002% Deviation: ± 75 kHz max.
Digital Hybrid Wireless Belt-Pack Transmitter Service and Repair If your system malfunctions, you should attempt to correct or isolate the trouble before concluding that the equipment needs repair. Make sure you have followed the setup procedure and operating instructions. Check the interconnecting cables and then go through the Troubleshooting section in this manual.
LIMITED ONE YEAR WARRANTY The equipment is warranted for one year from date of purchase against defects in materials or workmanship provided it was purchased from an authorized dealer. This warranty does not cover equipment which has been abused or damaged by careless handling or shipping. This warranty does not apply to used or demonstrator equipment. Should any defect develop, Lectrosonics, Inc. will, at our option, repair or replace any defective parts without charge for either parts or labor.
