H185 PLUG-ON TRANSMITTER 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. It is the best value available today. You will find that the H185 radiates more power than other standard handheld wireless microphones. This provides both greater operational range, as well as improved signal-to-noise ratio.
GENERAL TECHNICAL DESCRIPTION The H185 transmitter is comprised of four major functional subsystems: the input compressor, the mic preamp/gain control, the compandor, and the RF transmitter (see block diagram below). The input compressor is a low distortion shunt FET compressor situated before the mic preamp. Control signals for the compressor are derived after the mic preamp to eliminate any possibility of overload under any signal condition up to a maximum of 3 Volts input.
CONTROLS AND FUNCTIONS The H185 may be used with a wide variety of microphones. The 3-pin XLR type connector on the H185 allows the transmitter to be used with any dynamic microphone, as well as many two wire positive bias lavalier systems (such as those systems supplied by Lectrosonics). INPUT JACK Standard 3-pin Switchcraft XLR type. Pin 2 is signal, pin 3 is signal ground, and pin 1 is case ground (see schematic below). The H185 is self-locking onto a standard microphone.
The POWER LED is connected to a precision battery test circuit that continuously monitors battery voltage. The LED is at full brightness with a new 9 Volt alkaline or lithium battery. As the battery voltage drops during use, the LED brightness will also decrease. After 12 to 15 hours (25 to 30 hours with a lithium battery) the battery voltage will be about 7 Volts. The LED will be completely extinguished.
OPERATING INSTRUCTIONS 1) Insert the H185 into the selected microphone. Listen for the "click" that indicates the H185 has locked on to the microphone. Pull on the mic to insure proper locking has occurred. Figure 4 - Attaching the Microphone 2) Turn the power switch to the "MUTE" position on both the transmitter and the receiver. The "MUTE" position allows internal voltages to stabilize before audio signal paths are opened. 3) Hold the microphone as you will when you will be using it.
The LEVEL LED turns on at -10dB below full deviation. The LIMIT LED turns on at full deviation and indicates that the input shunt compressor is operating. The input compressor operates over a full 20dB range regardless of the gain control setting. The compressor uses a true absolute value circuit to detect both positive and negative peaks. The attack time is 2 milliseconds and the release time is 80 milliseconds.
TROUBLESHOOTING Before going through the following chart, be sure that you have a good battery in the transmitter red power LED on the transmitter panel should glow brightly. the SYMPTOM POSSIBLE CAUSE NO AUDIO IS HEARD BUT RECEIVER RF LED IS ON 1) On/Off switch is in "mute"position receiver or transmitter. 2) Microphone on/off switch is in "off" position. 3) Volume is turned down or off on transmitter or receiver. 4) Receiver not properly connected to other audio equipment.
SPECIFICATIONS AND FEATURES Operating frequencies: 150 to 216 MHz RF Power output: 50mW Deviation: +/- 15kHz Spurious radiation: 55dB below carrier Equivalent input noise: -126dBV Input level: Nominal 2mV to 300mV (before compression) Input impedance: 22k Ohms (compatible with all Lo-Z microphones) Input compressor: Soft compressor, 20 dB range allows 3 Volt max.
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.
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.
