DBZLM400Wireless Microphone Transmitter

LM400 FREQUENCY-AGILE UHF BELT-PACK TRANSMITTER OPERATING INSTRUCTIONS and trouble-shooting guide LECTROSONICS, INC. Rio Rancho, NM www.lectrosonics.com 2 LM400 LECTROSONICS, INC. TABLE OF CONTENTS INTRODUCTION ..................................................................................................... 3 GENERAL TECHNICAL DESCRIPTION............................................................... 4 CONTROLS AND FUNCTIONS ............................................................................. 6 BATTERY INSTALLATION..................................................................................... 8 OPERATING INSTRUCTIONS............................................................................... 8 OPERATING NOTES ............................................................................................. 9 ADJUSTING THE TRANSMITTER FREQUENCY................................................ 9 TROUBLESHOOTING .......................................................................................... 10 SPECIFICATIONS AND FEATURES.................................................................. 11 SERVICE AND REPAIR ....................................................................................... 12 RETURNING UNITS FOR REPAIR..................................................................... 12 WARRANTY ............................................................................................Back cover The LM400 transmitter is FCC type accepted under Part 74: 536-608 MHz and 614-806 MHz 3 Frequency-Agile UHF Belt-Pack Transmitter Rio Rancho, NM – USA INTRODUCTION Thank you for selecting the Lectrosonics LM400 frequency agile, belt-pack transmit- ter. The LM400 combines over 80 years of engineering experience with the very latest components, in a design that addresses the most demanding professional applica- tions. The design of the LM400 was the direct result of numerous conversations with users, staging and touring companies and dealers across the US. The specific concerns and needs brought up in these conversations led directly to the development of the operational features offered on the LM400. Two hundred fifty six frequencies are user selectable in 100kHz steps to alleviate interference problems in traveling venues, and the low frequency roll-off is user adjustable to adapt to varying acoustic environments and preferences. The LM400 is a rugged, machined aluminum package with a removable, spring loaded belt clip. The input section provides 3.3 Volts of bias voltage to power electret mics. Level indicating LEDs are provided on the control panel to make level settings quick and accurate, without having to view the receiver. The battery compartment accepts any 9 Volt alkaline battery and makes a positive connection via self-adjusting con- tacts. The antenna is a permanently attached 1/4 wavelength flexible bronze cable. Only the LM400 transmitter is covered in this manual. Companion receivers are covered in separate manuals. The LM400 will operate with any 400 Series Lectroson- ics receiver in the same frequency group. 4 LM400 LECTROSONICS, INC. GENERAL TECHNICAL DESCRIPTION GENERAL The 400 system uses 75kHz wide deviation for an extremely high signal to noise ratio. The switching power supplies provide constant voltages to the transmitter circuits from the beginning (9.3 Volts) to the end (5.5 Volts) of battery life. The input amplifier uses an ultra low noise op amp for quiet operation. It is gain controlled with a wide range dual envelope input compressor which cleanly limits input signal peaks over 30dB above full modulation. DIGITAL HYBRID TECHNOLOGY All wireless links suffer from channel noise to some degree, and all wireless microphone systems seek to minimize the impact of that noise on the desired signal. Conventional analog systems use compandors for enhanced dynamic range, at the cost of subtle artifacts (known as “pumping” and “breathing”). Wholly digital systems defeat the noise by sending the audio information in digital form, at the cost of some combination of power, bandwidth and resistance to interference. The Lectrosonics Digital Hybrid system overcomes channel noise in a dramatically new way, digitally encoding the audio in the transmitter and decoding it in the receiver, yet still sending the encoded information via an analog FM wireless link. This proprietary algorithm is not a digital implementation of an analog compandor but a technique which can be accomplished only in the digital domain, even though the inputs and outputs are analog signals. (As of this writing, the patent is still pending, so we cannot reveal detailed information about the algorithm at this time.) Phase Locked Loop Voltage Controlled Oscillator Freq Switches 11001001 A-D Converter Digital Signal Processor 11001001 D-A Converter Shunt Limiter Bicolor Modulation LEDs Microprocessor 9V Battery Switching Power Supply +3.3v +1.8v +9v -3v Hi/Lo Pass Filter Audio Encoded Audio + Pilot Tone 4MHz Reference Bicolor Power LED Audio Level Input Amp LF Roll Off Final Amplifier (Fits Switchcraft plug #850.) Mic Jack +3V Bias Supply LM400 Block Diagram 5 Frequency-Agile UHF Belt-Pack Transmitter Rio Rancho, NM – USA Channel noise still has an impact on received signal quality and will eventually overwhelm the receiver. The Digital Hybrid simply encodes the signal to use a noisy channel as efficiently and robustly as possible, yielding audio perfor- mance that rivals that of wholly digital systems, without the power and bandwidth problems inherent in digital transmis- sion. As always, these advantages come at a cost. The Digital Hybrid system requires fairly intensive digital processing in both the transmitter and the receiver. These processors cost money, take up space and consume power. The Digital Hybrid system also requires that the underlying RF link be of excellent quality, with better frequency response and distortion characteristics than that required by conventional systems. …

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ROGERS LABS, INC. LectroSonics Inc. 4405 W. 259th Terrace MODEL: LM400 Louisburg, KS 66053 Test #: 030129 FCCID#: DBZ LM400 Phone/Fax: (913) 837-3214 Test to: FCC Parts 2 and 74 Page 1 of 1 LM400BlkDia.doc 2/10/2003 Block Diagram for LM 400.

February 18, 2003 Timco Engineering Inc. 849 NW State Road 45 Newberry, FL 32669 Office of Engineering and Technology Federal Communications Commission Columbia, MD 21046 Applicant: Lectrosonics, Inc. 581 Laser Road Rio Rancho, NM 87124 Re: Confidentiality for submittal information regarding FCC ID number DBZ LM400 PRODUCT: Wireless Microphone transmitter operating under part 74. Dear Sirs: Lectrosonics, Inc. requests that the material in the Printed Circuit Board Layout, Schematics, and Operational Description be withheld from public disclosure in accordance with Section 0.459 of the Commissions Rules, 47 C.F.R. 0.459 (1998), following grant of the application. In support of this request, Lectrosonics, Inc. submits the following: 1. Identification of the specific information for which confidential treatment is sought: The materials set fourth in the Operational Description, Printed Circuit Board layout, and Schematics, which are segregated from the non-confidential exhibits of the application, are those for which confidentiality is sought. 2. Identification of the Commission proceeding in which the information was submitted or a description of the circumstances giving rise to the submission: The proceeding is that involving the application for equipment authorization (certification) under FCC ID No: DBZ LM400 3. Explanation of the degree to which the information is commercial or financial, or contains a trade secret or is privileged: This material includes a detailed theory of operation, circuit diagrams, (schematic diagrams) and detail printed circuit board layout. As such, this material is treated as highly confidential business information. ROGERS LABS, INC. 4405 West 259 th Terrace Louisburg, KS 66053 4. Explanation of the degree to which the information concerns a service that is subject to competition: The material for which confidentiality is sought is employed in the design and manufacture of this transmitting equipment that is offered on a highly competitive basis. Customers for this equipment have a variety of competing sources. 5. Explanation of how disclosure of the information could result in substantial competitive harm: Disclosure would, in effect, give away the fruits of the labors of Lectrosonics, Inc.’s engineering personnel, who have designed the equipment and the manufacturing process. Disclosure would also offer competitors additional unwarranted insight into the state of the product development, thereby allowing competitors an advantage, not available to Lectrosonics, Inc. 6. Identification of any measures taken by the submitting party to prevent unauthorized disclosure: The information for which confidential treatment is sought is kept confidential by Lectrosonics, Inc. and not made available to third parties except pursuant to non-disclosure agreements. 7. Identification of whether the information is available to the public and the extent of any previous disclosure of the information to third parties: To the knowledge of those preparing this application, the information has not been disclosed publicly heretofore. While the general theory of operation of this equipment has been the subject of numerous disclosures in industry and standards groups as well as in rule making proceedings of the FCC, the protection sought is narrowly drawn and pertains to certain specific implementations of this radio technology. 8. Justification of the period during which the submitting party asserts that the material should not be available for public disclosure: This material should not be disclosed for at least 25 years. While improvements in design are made relatively frequently, disclosure of the design information would lead to insights into both design and manufacturing techniques that could have an adverse competitive effect for many years to come. This equipment is designed for commercial, industrial, and governmental applications. As such, unlike most consumer equipment, this equipment could be used for more than a decade in some cases. As such, it is important that the design not be made available to unauthorized persons who might attempt to use knowledge of the design to compromise the applications for which the equipment will be employed. Should you require any further information, please contact the undersigned. Thank you for your consideration in this matter. Sincerely, Scot Rogers

ROGERS LABS, INC. LectroSonics Inc. 4405 W. 259th Terrace MODEL: LM400 Louisburg, KS 66053 Test #: 030129 FCCID#: DBZ LM400 Phone/Fax: (913) 837-3214 Test to: FCC Parts 2 and 74 Page 1 of 1 LM400Photos.doc 2/10/2003 Equipment photographs for LM400.

ROGERS LABS, INC. LectroSonics Inc. 4405 W. 259th Terrace MODEL: LM400 Louisburg, KS 66053 Test #: 030129 FCCID#: DBZ LM400 Phone/Fax: (913) 837-3214 Test to: FCC Parts 2 and 74 Page 1 of 1 LM400Label.doc 2/18/2003 FCC ID label and housing information for LM 400.

ROGERS LABS, INC. LectroSonics Inc. 4405 W. 259th Terrace MODEL: LM400 Louisburg, KS 66053 Test #: 030129 FCCID#: DBZ LM400 Phone/Fax: (913) 837-3214 Test to: FCC Parts 2 and 74 Page 1 of 1 LM400IntPho.doc 2/10/2003 Internal photographs of Printed circuit board for LM400.

ROGERS LABS, INC. LectroSonics Inc. 4405 W. 259th Terrace MODEL: LM400 Louisburg, KS 66053 Test #: 030129 FCCID#: DBZ LM400 Phone/Fax: (913) 837-3214 Test to: FCC Parts 2 and 74 Page 1 of 1 LM400Tune.doc 2/10/2003 LM400 TUNE-UP PROCEDURE EQUIPMENT REQUIRED Audio signal generator capable of producing signals of -60 dBV to +10 dBV into 600 ohms at frequencies of 10 Hz to 50 kHz. Used in development: Audio Precision ATS-1. RF spectrum analyzer with sensitivity of -100 dBm or better, a frequency range of 10 MHz to 1.5 GHz or wider, a terminating impedance of 50 ohms, and capability of handling an input level of + 25 dBm without overload or significant distortion. Used in development: Hewlett Packard 8560E. Frequency counter covering 10 MHz to 806 MHz with an accuracy of +/- 100 Hz and readout to the nearest 10 Hz or better. This function may be resident on many higher end spectrum analyzers. Used in development: Boonton 8200 and Hewlett Packard 8560E. Deviation meter capable of measuring frequency deviation from 0 to +/-100 kHz at 470 MHz to 806 MHz with an RF power level of +25 dBm or less in an FM system modulated by audio frequencies from 10 Hz to 50 kHz. The unit should also have a demodulated audio output. Used in development: Boonton Model 8200. Digital multimeter capable of measuring current to at least 100 ma and voltage to 10 VDC with an accuracy of 3% or better. Used in development: Fluke Model 85. Audio analyzer capable of measuring audio distortion to 0.05% or less over a frequency range of at least 10 Hz to 50 kHz. The unit should also have an output of residual distortion to an external measurement device. Used in development: Audio Precision ATS-1. Oscilloscope with good audio response and sensitivity of at least 10 mv/cm with associated high impedance probe is also needed for evaluation of residual distortion. Used in development: Tektronix Model 224. Power supply for bench top use capable of supplying 9 VDC at 100 ma of current is needed. Both current and voltage should be metered. The supply should also have a variable current limit adjustment. Used in development: Leader Model LPS-15SL. RF power meter or 50 ohm RF probe and associated meter capable of measuring RF power to 806 MHz at power levels to +20 dBm to an accuracy of 5% is also required. Many higher-end spectrum analyzers have this capability available as part of the cursor functions. Used in development: Hewlett Packard 8560E and Hewlett Packard 437B. AC RMS voltmeter with a range of at least +20 dBV to -60 dBV (10 Vrms to 1 mVrms) readable to within +/- 3% is needed. Used in development: Audio Precision ATS-1. RECOMMENDED TEST FIXTURES An audio cable with a 2.5 mm micro phone plug on one end. The other end should be appropriate to the audio signal generator. Note that DMMs may read inaccurately in RF fields. An antenna that attaches to the spectrum analyzer and frequency counter to receive the signal radiated from the fixed antenna on the unit under test. GENERAL NOTES The tuning capacitors are small and have a very small tuning socket. An alignment tool, which fits the tuning capacitors, is a must. CHECKING THE POWER INDICATOR Substitute the power supply for the battery. The supply should be current limited to 100 ma to protect the LM400 from shorts and over current due to misalignment. Set the supply for 9 VDC ROGERS LABS, INC. LectroSonics Inc. 4405 W. 259th Terrace MODEL: LM400 Louisburg, KS 66053 Test #: 030129 FCCID#: DBZ LM400 Phone/Fax: (913) 837-3214 Test to: FCC Parts 2 and 74 Page 2 of 1 LM400Tune.doc 2/10/2003 and connect it to the LM400. The current drain should 70 ma or less. When properly aligned this value should be nominally 60 ma with only the power LED illuminated. The green battery indicator LED located on the front panel should be brightly lit. Adjust the power supply voltage downward while watching the Power LED. The LED should change to red at 7.3 volts, and flashing red at 6.8 volts. This completes the power indicator checks. PREPARATION All alignment and adjustment is done with the power supply set to 9 VDC and current limited at 100 ma. All measurements are referenced to the RF-cold PC ground plane. A 9-volt supply should be connected to the battery contact and ground. PRESET ADJUSTMENTS The frequency control switches are on the edge of the board. The left switch is SW-3 and sets the frequency in 1.6 MHz steps. The right switch is SW-2 and sets the frequency in 100 kHz steps. The switch notation used here will be (# #) or (SW-3 SW-2) or steps of (1.6 MHz 100 kHz). For example (A 7) means set SW-3 at A and set SW-2 at 7. Set the BCD switches, SW-3 and SW-2, to the highest frequency ( F F). Chances are the loop will not be locked and the lock detector will inhibit the output of the transmitter. However, the oscillator will still free run at some frequency close to the set frequency (+- 15 MHz). The oscillator will be detectable at a low level by the analyzer. Set the mic input level (R28 on the front panel) to maximum. OSCILLATOR ALIGNMENT Adjust C73 to move the free running oscillator toward the desired frequency. Once the oscillator is close enough to the frequency set by the BCD switches, it will lock in. The RF output of the transmitter will now be enabled since the PLL (phase locked loop) is now locked. Continue to adjust C73 until the voltage at TP5 is 3 Volts. This is a temporary adjustment of C73 and is done so that the voltages on the modulation varactor D2 can be adjusted to a final setting without interacting with the tuning varactor D3. AUDIO ADJUSTMENT To set the audio distortion it is necessary to disable the DSP emulation and pilot tone. This is done by shorting Pin-1 to Pin-7 on test socket J-2, adjusting the BCD switches to (D 0), and removing the short on the test socket to disable the DSP emulation. Next, short Pin-1 to Pin-7 on J-2 and set the BCD switches to (D 1) to remove the pilot tone. Then set the BCD switches to (8 0) for the center of the operating range of the …

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TEST REPORT For APPLICATION of CERTIFICATION for LECTROSONICS, INC. 581 Laser Road Rio Rancho, NM 87124 Larry Fisher Vice President of Engineering MODEL: LM400 NAME: Wireless Microphone Transmitter FREQUENCY: 537.6 – 608.0, 614.0 - 793.5 MHz FCC ID: DBZ LM400 Test Date: January 29, 2003 Certifying Engineer: Scot D. Rogers ROGERS LABS, INC. 4405 West 259 TH Terrace Louisburg, KS 66053 PHONE: (913) 837-3214 FAX: (913) 837-3214 This report shall not be reproduced except in full, without the written approval of the laboratory. This report must not be used by the client to claim product endorsement by NVLAP or any agency of the U.S. Government. ROGERS LABS, INC. 4405 West 259 th Terrace Louisburg, KS 66053 Phone / Fax (913) 837-3214 NVLAP Accredited Laboratory NVLAP Lab Code: 200087-0 ROGERS LABS, INC. Lectrosonics, Inc. 4405 West 259 TH Terrace MODEL: LM400 Louisburg, KS 66053 Test #: 030129 FCC ID DBZ LM400 Phone/Fax: (913) 837-3214 Test to: FCC Parts 2 & 74 Page 2 of 21 LM400Testrpt.DOC 01/31/2003 TABLE OF CONTENTS FORWARD: 3 APPLICABLE STANDARDS & TEST PROCEDURES 3 LIST OF TEST EQUIPMENT 3 2.1033(C) APPLICATION FOR CERTIFICATION: 4 2.1046 RF POWER OUTPUT 6 Measurements Required: 6 Test Arrangement: 7 Results: 7 2.1047 MODULATION CHARACTERISTICS 8 Measurements Required: 8 Test Arrangement: 8 Results: 8 2.1049 OCCUPIED BANDWIDTH 10 Measurements Required: 10 Test Arrangement: 10 Results: 11 2.1051 SPURIOUS EMISSIONS AT ANTENNA TERMINALS 11 Measurements Required: 11 Test Arrangement: 12 Results: 12 2.1053 FIELD STRENGTH OF SPURIOUS RADIATION 12 Measurements Required: 12 Test Arrangement: 12 Results : 13 2.1055 FREQUENCY STABILITY 15 Measurements Required: 15 Test Arrangement: 15 Results: 17 APPENDIX 18 NVLAP Accredited Laboratory NVLAP Lab Code: 200087-0 ROGERS LABS, INC. Lectrosonics, Inc. 4405 West 259 TH Terrace MODEL: LM400 Louisburg, KS 66053 Test #: 030129 FCC ID DBZ LM400 Phone/Fax: (913) 837-3214 Test to: FCC Parts 2 & 74 Page 3 of 21 LM400Testrpt.DOC 01/31/2003 FORWARD: In accordance with the Federal Communications Code of Federal Regulations, dated October 1, 2001, Part 2 Subpart J, Paragraphs 2.907, 2.911, 2.925, 2.926, 2.1031 through 2.1057 and; Part 74 Subpart H; Paragraphs 74.801 through 74.861 the following is submitted: Applicable Standards & Test Procedures a) In accordance with the Federal Communications Code of Federal Regulations, dated October 1, 2001, Part 2, Subpart J, Paragraphs 2.907, 2.911, 2.913, 2.925, 2.926, 2.1031 through 2.1057, and applicable paragraphs of Part 74 the following is submitted. b) Test procedures used are the established Methods of Measurement of Radio-Noise Emissions as described in ANSI 63.4- 1992 and TIA/EIA 603. List of Test Equipment A Hewlett Packard 8591EM and or 8562A Spectrum Analyzer was used as the measuring device for the emissions testing. The analyzer settings used are described in the following table. Refer to the Appendix for a complete list of Test Equipment. NVLAP Accredited Laboratory NVLAP Lab Code: 200087-0 ROGERS LABS, INC. Lectrosonics, Inc. 4405 West 259 TH Terrace MODEL: LM400 Louisburg, KS 66053 Test #: 030129 FCC ID DBZ LM400 Phone/Fax: (913) 837-3214 Test to: FCC Parts 2 & 74 Page 4 of 21 LM400Testrpt.DOC 01/31/2003 HP 8591EM SPECTRUM ANALYZER SETTINGS CONDUCTED EMISSIONS: RBW AVG. BW DETECTOR FUNCTION 9 kHz 30 kHz Peak/Quasi Peak RADIATED EMISSIONS (30 – 1000 MHz): RBW AVG. BW DETECTOR FUNCTION 120 kHz 300 kHz Peak/Quasi Peak HP 8562A SPECTRUM ANALYZER SETTINGS RADIATED EMISSIONS (1 – 40 GHz): RBW AVG. BW DETECTOR FUNCTION 1 MHz 1 MHz Peak/Average ANTENNA CONDUCTED EMISSIONS: RBW AVG. BW DETECTOR FUNCTION 100 kHz 300 kHz Peak 2.1033(C) Application for Certification: (1) The full name and mailing address of the manufacturer of the device and the applicant for certification. Lectrosonics, Inc. 581 Laser Road Rio Rancho, NM 87124 (2) FCC identifier. DBZ LM400 (3) A copy of the installation and operating instructions to be furnished the user. Refer to the instruction manual furnished with this application for details. (4) Type or types of emission. 180KF3E (5) Frequency range. 537.6 to 608.0 MHz and 614.0- 793.5 MHz. (6) Range of operating power values or specific operating power levels, and description of any means provided for variation of operating power. The output power is factory set to 70 mW (nominal). The EUT has no provision for operator variation of the output power. NVLAP Accredited Laboratory NVLAP Lab Code: 200087-0 ROGERS LABS, INC. Lectrosonics, Inc. 4405 West 259 TH Terrace MODEL: LM400 Louisburg, KS 66053 Test #: 030129 FCC ID DBZ LM400 Phone/Fax: (913) 837-3214 Test to: FCC Parts 2 & 74 Page 5 of 21 LM400Testrpt.DOC 01/31/2003 (7) Maximum power rating as defined in the applicable part(s) of the rules. As stated in CFR 47, 74.861(e)(ii), the maximum permissible output power allowed is 250 mW. (8) The dc voltages applied to and dc currents into the several elements of the final radio frequency amplifying device for normal operation over the power range. The EUT final amplification stage runs at 3.2 volts with 36 mA current for a power requirement of 115 mW. (9) Tune-up procedure over the power range, or at specific operating power levels. Refer to the tune-up procedure furnished with this application for details. (10) A schematic diagram and a description of all circuitry and devices provided for determining and stabilizing frequency, for suppression of spurious radiation, for limiting modulation, and for limiting power. Refer to the schematics furnished with this application for details. (11) A photograph or drawing of the equipment identification plate or label shows the information to be placed thereon. Refer to the FCC identification label information furnished with this application for details. (12) Photographs (8'' x 10'') of the equipment of sufficient clarity to reveal equipment construction and layout, including meters, if any, and labels for controls and meters and sufficient views of the internal…

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ROGERS LABS, INC. LectroSonics Inc. 4405 W. 259th Terrace MODEL: LM400 Louisburg, KS 66053 Test #: 030129 FCCID#: DBZ LM400 Phone/Fax: (913) 837-3214 Test to: FCC Parts 2 and 74 Page 1 of 1 LM400TstPhot.doc 2/10/2003 Test setup photographs for LM400.