Lectrosonics Pro 4 Channel User Manual

PRO 4 CHANNEL

MULTI CHANNEL WIRELESS SYSTEM

WITH DM4/DM4D DISTRIBUTION MODULE

OPERATING INSTRUCTIONS

and trouble-shooting guide

LECTROSONICS, INC.

Rio Rancho, NM

INTRODUCTION

The PRO 4 CHANNEL system is a high quality, multi-channel wireless microphone system designed for sound
stage, studio, and theater applications. Multi-channel problems such as interaction of receivers, intermodulation
and desensitization, etc. have been eliminated through creative engineering and superior design. The integral DM4
distribution module provides convenience of operation from a common antenna system and power supply without
degrading the performance of the receivers. In fact, the additional RF filtering in the DM4 module actually improves
the already outstanding selectivity of the R185 receivers.

The PRO 4 CHANNEL system is available in two versions Standard and Diversity. The Standard version
consists of a DM4 RF/Power distribution module and a DC power supply installed in a 19" rack mount. The
Standard version is available with up to four R185 wireless receivers and companion transmitters, or by itself to
combine existing R185 receivers.

The Diversity system consists of a DM4D RF/Power distribution module and up to four DR185 wireless receivers
and companion transmitters.

TABLE OF CONTENTS

INTRODUCTION .......................................... 2

GENERAL TECHNICAL DESCRIPTION .......................... 2

FRONT PANEL DESCRIPTION ................................ 3

REAR PANEL DESCRIPTION ................................. 4

INSTALLATION ........................................... 5

OPERATING INSTRUCTIONS ................................. 5

TROUBLESHOOTING ....................................... 6

SPECIFICATIONS ......................................... 7

SERVICE AND REPAIR ..................................... 8

RETURNING UNITS FOR REPAIR ............................. 8

WARRANTY ....................................... Back cover

1

GENERAL TECHNICAL DESCRIPTION

RF FILTERING & DISTRIBUTION

POWER SUPPLY & DISTRIBUTION

POLYFUSES

REGULATOR

HELICAL

RESONATORS

SPLITTER

AND/OR

COMBINER

RF

AMP

SPLITTER

&

ISOLATOR

SPLITTER

&

ISOLATOR

RF

AMP

DM4 Diversity Module

POWER
SUPPLY

RF to
Receivers

12V DC Power
to Receivers

The PRO 4 CHANNEL consists of two sub-systems; the frame which contains the receivers, receiver mounting
hardware, and DC power supply, and the CDM4 RF/power distribution module.

The DM4 RF/power distribution module is the heart of the PRO 4 CHANNEL system. Helical resonators in the front
end of the RF section attenuate out-of-band RF signals preventing intermodulation and front end overload.
Following the resonators is a low noise, low gain RF amplifier designed to evenly compensate for splitter losses in
the stage that follows. A precision splitter/isolator divides the RF signal into four isolated signals preventing
spurious RF coupling between receivers. The splitter/isolator is termination independent which prevents
mismatched or disconnected RF outputs from affecting the other receivers.

Power is supplied to the DM4 module from the DC power supply module mounted on the frame. All power circuits
are protected by internal auto-reset fuses in the DM4. Should the power to one receiver fail, the others will
continue to operate.

Figure 1 - PRO 4 CHANNEL Block Diagram

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