INSTRUCTION MANUAL UM450 Frequency-Agile UHF Belt-Pack Transmitter Featuring Digital Hybrid Wireless™ Technology (US Patent Pending) Fill in for your records: Serial Number: Purchase Date: Rio Rancho, NM, USA www.lectrosonics.
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Frequency-Agile UHF Belt-Pack Transmitter Thank you for selecting the Lectrosonics UM450 frequency agile, belt-pack transmitter. The UM450 combines over 80 years of engineering experience with the very latest components, in a design that addresses the most demanding professional applications. The design of the UM450 was the direct result of numerous conversations with users, staging and touring companies and dealers across the US.
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Frequency-Agile UHF Belt-Pack Transmitter Table of Contents General Technical Description .............................................................................................................................................................. 6 Introduction ........................................................................................................................................................................................... 6 Digital Hybrid Technology ...............................
UM450 General Technical Description Introduction The 400 system uses 75 kHz 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 30 dB above full modulation.
Frequency-Agile UHF Belt-Pack Transmitter No Pre-Emphasis/De-Emphasis The signal to noise ratio of the 400 system is high enough to preclude the need for conventional preemphasis (HF boost) in the transmitter and de-emphasis (HF roll off) in the receiver.
UM450 Controls and Functions Input Jack Power LED Power ON/OFF Switch Low Frequency Roll Off Control AUDIO LEVEL Control Modulation LEDs ANTENNA Jack E D C B A F 0 1 2 3 4 5 9 8 7 6 E D C B A F 0 1 2 3 4 5 9 8 7 6 1.6M 100K Frequency Select Switches Input Jack The input on the UM450 accommodates virtually every lavaliere, hand-held or shotgun microphone available. Different line level signals can also be accommodated. (See Line Level Signals and Transmitter 5-Pin Input Jack Wiring.
Frequency-Agile UHF Belt-Pack Transmitter Modulation LEDs The Modulation LEDs provide a visual indication of the input audio signal level from the microphone. These two bicolor LEDs can glow either red or green to indicate modulation levels.
UM450 Battery Installation Operating Instructions The transmitter is powered by a standard alkaline or lithium 9 Volt battery. It is important that you use ONLY an ALKALINE or LITHIUM battery for longest life. Standard zinc-carbon batteries marked “heavy-duty” or “long-lasting” and Ni-Cad batteries are not adequate. Alkaline batteries provide approximately 1.5 hours of operation. Lithium batteries can be used to provide up to 4.5 hours.
Frequency-Agile UHF Belt-Pack Transmitter Attaching a Microphone and Adjusting Gain 1) Ensure the battery is in good condition. 2) Insert the microphone plug into the input jack, aligning the pins; be sure that the connector locks. 3) Attach the antenna to the SMA connector on the top of the transmitter. 4) Mute the associated receiver’s audio output. 5) Turn on the transmitter. 6) Position the microphone in the location you will use in actual operation.
UM450 Microphone Cord Termination Caution: When wiring the connector, do not use the connector body for any electrical connections. A common mistake is to use the connector body as an audio ground. The connector body is already used as an RF ground on VHF models and no other use is permitted. TA5F Connector Assembly Mic Cord Stripping Instructions 1 4 5 2 3 NOTE: This termination is required on VHF transmitters and will still work fine on UHF transmitters. 12 LECTROSONICS, INC.
Frequency-Agile UHF Belt-Pack Transmitter 5-Pin Input Jack Wiring The wiring diagrams shown on the next page 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. respect to the effect of the RF on the microphone capsule. Even in transmitters that utilize a “dangling wire,” the microphone is still part of the “ground plane” and is therefore still in the antenna circuit.
UM450 The best RF protection is accomplished by installing RF bypass capacitors at the mic capsule. If this is not possible, or if you are still having problems, capacitors can be installed on the mic pins inside the TA5F connector housing. Install the capacitors as follows: Use 330 pF capacitors. Capacitors are available from Lectrosonics. Please specify the part number for the desired lead style.
Frequency-Agile UHF Belt-Pack Transmitter Wiring Hookups for Different Sources PIN SHIELD BIAS 3 WIRE ELECTRET MIC POSITIVE BIAS PIN 1 2 3 AUDIO 4 5 SHIELD 4 3 5 1 2 TA5F PLUG 2 WIRE ELECTRET MIC NEGATIVE BIAS AUDIO SHIELD 2 WIRE ELECTRET MIC POSITIVE BIAS SHIELD 1 2 AUDIO 3 4 5 4 3 5 1 2 TA5F PLUG 3 WIRE ELECTRET MIC NEGATIVE BIAS Rio Rancho, NM AUDIO 3 4 5 2 3 4 LINE LEVEL RCA or 1/4 " PLUG 5 1 3 4 3 5 1 2 TA5F PLUG 1 2 TA5F PLUG 4 3 5 1 2 TA5F PLUG (See notes on “LI
UM450 Replacement Parts and Accessories Item Model/Part Number Replacement wire belt clip Lectrosonics #BCWire Replacment whip antenna Lectrosonics AMM (xx) specify frequency block (xx) UHF Transmitter Antenna Specifications Measure the length of the whip that protrudes outside of the SMA connector to find the operating Frequency Block All Lectrosonic UHF transmitter antennas follow the color code specifications in the chart below to identify operating frequency block range.
Frequency-Agile UHF Belt-Pack Transmitter Troubleshooting Before going through the following chart, be sure that you have a good battery in the transmitter. It is important that you follow these steps in the sequence listed.
UM450 Specifications and Features Operating frequencies: Frequency selection: RF Power output: Pilot tone: Frequency stability: Deviation: Spurious radiation: Equivalent input noise: Input level: Input impedance: Input compressor: Gain control range: Modulation indicators: Low frequency roll-off: Audio frequency response (overall system): Controls: Audio Input Jack: Antenna: Power Consumption: Battery: Battery Life: Weight: Dimensions: Block 21: 537.600 - 563.100 Block 22: 563.200 - 588.
Frequency-Agile UHF 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.
