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 5 and 6). 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 Quick Start Steps...................................................................................................................................................................................1 Introduction..............................................................................................................................................................................................3 About Digital Hybrid Wireless..........................................................
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 No Pre-Emphasis/De-Emphasis The Digital Hybrid Wireless system employs a DSPgenerated supersonic tone (pilot tone), using it as a kind of signature, so the receiver can mute even strong signals that aren’t from the appropriate transmitter. The pilot tone also helps to ensure that the receiver is quiet when the transmitter is turned on and off.
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 contacts can be cleaned with alcohol and a cotton swab, or a clean pencil eraser. Be sure not to leave any remnants of the cotton swab or eraser crumbs inside the compartment.
LMb Operating Instructions Battery icon Input Jack 5A -20 0 Menu navigation buttons* Programmable Switch Power Button Move switch toward the white dot to turn it on -10 Belt clip mounting hole Modulation LEDs BAT -40 Slide door outward to open battery door and access batteries Power/Function LED 623.400 BAT IR PORT RF Indicator -20 Battery Status LED * The DOWN arrow will turn the LEDS off and the UP arrow will turn them on when the Main Window (no menu) is displayed.
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: • Power - turns the power on and off • Mute - mutes the audio when switched on • TalkBk (talkback) - redirects the audio to a different output channel on the receiver (with receivers that offer this function) • (none) - disables the switch ProgSw ProgSw Power Mute Frequency set to fractional 25 kHz step, but step size changed to 100 kHz.
Digital Hybrid Wireless Belt-Pack Transmitter Selecting the Compatibility (Compat) Mode When used with a Lectrosonics Digital Hybrid Wireless® receiver, the best audio quality will be achieved with the system set to the Nu Hybrid compatibility mode. Gain Freq. ProgSw Compat Compat Use the UP and DOWN arrows to select the desired mode, then press the BACK button twice to return to the Main Window.
LMb Selecting Frequency Selecting Frequency Using Two Buttons The setup screen for frequency selection offers several ways to browse the available frequencies. Freq. b 19 Gain Freq. ProgSw Compat 51 494.500 Hold the MENU/SEL button in, then use the arrow buttons for alternate increments. 100 kHz Mode Press MENU/ SEL to select one of four fields to make adjustments Freq. b 19 10 MHz steps 494.500 Freq. b 19 10 MHz steps These two fields always step in the same increments Freq. b 19 51 51 494.
Digital Hybrid Wireless Belt-Pack Transmitter Selecting Audio Polarity (Phase) Audio polarity can be inverted at the transmitter so the audio can be mixed with other microphones without comb filtering. The polarity can also be inverted at the receiver outputs. Compat StepSiz Phase Locked Phase Pos. Neg. Adjusting LCD Backlight For viewing the LCD in dimly lit conditions, the backlight can be turned on continuously or set to turn off automatically after either 30 seconds or 5 minutes.
LMb 5-Pin Input Jack Wiring Audio 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. 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 hookups 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: http://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 P/N 26526 Wire belt clip BCHINGED Hinged 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” p
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. Gain control turned all the way down. Batteries are inserted incorrectly. Check power LED. Mic capsule is damaged or malfunctioning.
LMb Specifications and Features Operating Frequencies: Band A1: 470.100 - 537.575 Band B1: 537.600 - 607.950 Frequency Selection Steps: Selectable; 100 kHz or 25 kHz RF Power output: 50 mW Compatibility Modes (3) Nu Hybrid, Mode 3, IFB Pilot tone: 3.5 kHz deviation (Nu Hybrid) Frequency Stability: ± 0.002% Spurious radiation: Compliant with ETSI EN 300 422-1 v1.4.
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.