UM700 DIGITAL FREQUENCY-AGILE UHF BELT-PACK TRANSMITTER OPERATING INSTRUCTIONS and trouble-shooting guide LECTROSONICS, INC. Rio Rancho, NM www.lectrosonics.
TABLE OF CONTENTS INTRODUCTION .................................................................................................. 3 GENERAL TECHNICAL DESCRIPTION ............................................................ 4 CONTROLS AND FUNCTIONS .......................................................................... 6 BATTERY INSTALLATION ................................................................................... 8 OPERATING INSTRUCTIONS ........................................................
Frequency Agile UHF Belt-Pack Transmitter INTRODUCTION The 700 Series wireless system was designed to take advantage of the superior audio performance provided by DSP audio signal processing and the security provided by proprietary digital and encrypted digital radio operation.
GENERAL TECHNICAL DESCRIPTION GENERAL The 700 Series wireless system uses digital modulation for an extremely high signal to noise ratio and freedom from distortion and compandor artifacts. The input preamplifier uses an ultra low noise op amp for an excellent signal to noise ratio. A dual-envelope limiter is implemented by the DSP firmware to cleanly limit input signal peaks up to 30dB above full modulation.
Frequency Agile UHF Belt-Pack Transmitter A/D CONVERTER AND DSP PROCESSOR The processed audio signal enters the A/D converter to generate a digital signal for the modulator. A proprietary algorithm is used for sampling and compression to minimize noise and distortion, and provide a wide, flat frequency response. The signal then enters the modulator to generate a digitally modulated radio signal.
CONTROLS AND FUNCTIONS FREQUENCY 1.6MHz 100kHz LECTROSONICS UM700 BLK 20 (BK) 512.0 - 537.5 OFF ON AUDIO LEVEL 75 Hz 35 150 LF ROLL OFF ANTENNA FCCID:DBZUM700 Lectrosonics, Inc. Made in U.S.A. SN: XXXX INPUT JACK The input jack on the UM700 is a Switchcraft TA5M connector that accommodates virtually every lavalier, hand-held or shotgun microphone available, with positive or negative bias. The input will also cleanly handle line level signals up to 300 mV before limiting.
Frequency Agile UHF Belt-Pack Transmitter AUDIO LEVEL CONTROL Used to adjust the audio input level for proper modulation. AUDIO LEVEL LEDS Indicate the proper setting of the MIC LEVEL control. The two audio level LED’s are bi-colored (red/.
BATTERY INSTALLATION 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 “longlasting” are not adequate. Ni-cad rechargeable batteries will only provide 1.5 hours of operation, or less, and will run down quite abruptly. Unless it is cold, alkaline batteries provide over 4.5 hours of operation.
Frequency Agile UHF Belt-Pack Transmitter OPERATING NOTES The AUDIO LEVEL control knob should not be used to control the volume of your sound system or recorder levels. This gain adjustment matches the transmitter gain with the user’s voice level and microphone positioning. If the audio level is too high — both LEDs will be Red frequently or stay Red. This condition may reduce the dynamic range of the audio signal. If the audio level is too low — neither LED will light, or only one LED will flicker Green.
MICROPHONE CORD TERMINATION TA5F Connector Assembly 1 4 5 2 3 VIEW FROM SOLDER SIDE OF PINS 0.15" 0.3" Heatshrink Tubing Mic Cord Stripping Instructions Caution! Do not allow the shield wire to touch any metal part of the connector shell. The shield wire is the antenna on VHF models and poor operating range will result.
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. 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.
RF BYPASSING 2 WIRE MIC Some mics require RF protection to keep the radio signal from affecting the capsule, even though the transmitter input circuitry is already RF bypassed (see schematic diagram). 3 WIRE MIC Preferred locations for bypass capacitors SHIELD SHIELD If the mic is wired as directed, and you are having difficulty with squealing, high noise, or poor frequency response; RF is likely to be the cause.
Frequency Agile UHF Belt-Pack Transmitter A6U UHF ANTENNA This is a full size cutting template. Lay the actual antenna on top of this drawing and cut at the mark for the desired frequency group. Install cap on end of antenna after cutting to length. Colored sleeve 21 22 23 24 26 25 28 27 30 29 32 33 31 Black cap Frequency Blocks Kits are shipped from the factory with caps of the various colors plus a black cap.
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. SYMPTOM POSSIBLE CAUSE TRANSMITTER BATTERY LED OFF 1) Battery is inserted backwards. 2) Battery is dead. NO TRANSMITTER MODULATION LEDs 1) Gain control turned all the way down. 2) Battery is in backwards. Check power LED. 3) Mic capsule is damaged or malfunctioning. 4) Mic cable damaged or mis-wired.
Frequency Agile UHF Belt-Pack Transmitter SPECIFICATIONS AND FEATURES Operating Principle: Proprietary digital modulation with encryption Operating frequencies: 525.000 to 870.000 MHz depending upon local regulations Frequency selection: 256 frequencies in 100kHz steps RF Power output: 50 mW (nominal) Frequency stability: ± 0.001% Equivalent input noise: –126 dBV Input level: Nominal 2 mV to 300 mV, before limiting.
Specifications subject to change without notice. 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.
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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, we will, at our option, repair or replace any defective parts without charge for either parts or labor.
