UR190 UHF COMPACT RECEIVER OPERATING INSTRUCTIONS and trouble-shooting guide LECTROSONICS, INC.
INTRODUCTION Thank you for selecting the Lectrosonics Professional Series wireless microphone system. This system represents well over 10 years of manufacturing experience in wireless microphones, and almost 70 years of design experience. The UR190 UHF receiver design is the result of surveying the needs of professional video producers, ENG cameramen and many others in the broadcast and pro video industry. Hundreds of conversations with dealers and end-users developed the final parameters for the design.
GENERAL TECHNICAL DESCRIPTION Ant Helical Resonator Double Filter Balanced Mixer GAsFET Preamp 1st IF Amp and Crystal Filters Audio Level RF LED 2nd Mixer Squelch Demodulator Helical Resonator Filter 2nd IF Amp w/LC Filters 1st Local Oscillator 2nd Local Oscillator A FC Output Amp & Level Control CH12 Jack +9V Reg Polarity Protection On Balanced XLR Output Off 16 kHz Lo-Pass Filter Dual-Band Compandor +9V 0dB LED Power L ED Headphone Output Hdph Amp and Level Control -20 LED Figure 1 - U
The Dual Band Compandor is driven by a multiple pole active low-pass filter. The filter ensures that supersonic noise will not cause the compandor to increase gain incorrectly. This filter also drives the -20dB and 0dB modulation LEDs. Traditionally, compandors have been a source of distortion in wireless microphone systems. The basic problem with conventional systems is that the attack and decay times are always a compromise.
CONTROLS AND FUNCTIONS RECEIVER FRONT PANEL MODULATION LEDs Indicate the modulation (audio level) of the incoming signal, and can be used for proper adjustment of the transmitter’s "MIC LEVEL" or "GAIN". The -20 LED glows when the transmitter modulation is at a high enough level to produce a good audio signal-to-noise ratio. It will normally flicker, or stay lit as you speak into the microphone. The 0dB lamp indicates a "peak," showing that the transmitter modulation is at maximum.
RF LED Lights when the transmitter is turned on and the receiver has a good signal. When the carrier signal from the transmitter is too weak to produce a clean audio signal, the lamp will go out. MINI PHONE JACK Provides a monitor, separate from the rear panel XLR audio output. The output level from this jack is controlled by both the OUTPUT control and the recessed trim-pot on the side panel.
RECEIVER REAR PANEL 12 VDC INPUT Connects to the supplied CH-12 AC adapter for powering the receiver from a 110/120V AC source. The receiver may also be powered from external 12 volt DC sources using the correct plug (Switchcraft S-760 power plug). A diode bridge is used in the external power input, so that the UR190 will operate properly from either polarity. AUDIO OUTPUT Supplies a balanced, low impedance output at microphone level. The audio signal is output on pins 2 and 3, while pin 1 is ground.
ANTENNA USE AND PLACEMENT Connect the antenna to the front panel jack. Position the antenna so that it is not within 3 or 4 feet of large metal surfaces. If this is not possible, try to position the antenna so that it is as far away from the metal surface as is practical. It is also good to position the receiver so that there is a direct "line of sight" between the transmitter and the receiver antenna.
OPERATING INSTRUCTIONS 1) Connect the power cord. 2) Attach and extend the antenna. 3) Connect the audio cable. 4) Set the front panel switch to either "EXT" or "INT", depending upon the power source. Check to see that the red POWER LED lights up. 5) THIS IS PERHAPS THE MOST IMPORTANT STEP IN THE SET UP PROCEDURE. Adjust the transmitter "gain". See your transmitter manual (Operating Instructions section) for specific directions on the proper gain adjustment of your particular transmitter.
TROUBLESHOOTING Before going through the following chart, be sure that you have a properly connected AC adapter. The POWER LED should glow brightly.
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 out the inter-connecting cords and then go through the TROUBLE SHOOTING section in the manual We strongly recommend that you do not try to repair the equipment yourself and do not have the local repair shop attempt anything other than the simplest repair.
SPECIFICATIONS AND FEATURES Operating Frequencies: 470MHz to 608MHz, crystal controlled Sensitivity: Better than 0.35 uV for 20dB SINAD; 1.5 uV for 50dB S/N ratio Signal/Noise Ratio: 106dB A-weighted Squelch Quieting: greater than 106dB AM Rejection: -60dB (10uV to 0.1 Volts) Modulation Acceptance: ±15kHz Image and Spurious Rejection: greater than 100dB Third Order Intercept: -5 dBm Audio Outputs: XLR: Headphone: 200 Ohms balanced; 100mV max. 0.
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.
