Lectrosonics M170XLR User Manual

M170

Belt Pack Transmitter

OPERATING INSTRUCTIONS

and trouble-shooting guide

LECTROSONICS, INC.

Rio Rancho, NM

INTRODUCTION

Thank you for selecting the M170 Series transmitter. The M170 Series transmitters operate on high
band frequencies from 150 MHz to 216 MHz. It is offered in five different versions to meet your specific
needs. This manual covers all five versions.

Only the M170 series transmitters are covered in this manual. Receivers are covered in separate
manuals. All versions of the M170 Series transmitters will operate with any Lectrosonics high band
VHF receiver. A frequency matched transmitter/receiver combination makes up a "wireless system".

If you are new to wireless microphones, you will discover a new freedom of movement and level of
convenience. If you are an experienced wireless user, you will be pleased with the versatility and
superior performance of the M170 design.

TABLE OF CONTENTS

INTRODUCTION .......................................... 1

GENERAL DESCRIPTION ................................... 3

M170 VARIATIONS ........................................ 4

CONTROLS AND FUNCTIONS ................................ 5

BATTERY INSTRUCTIONS ................................... 7

OPERATING INSTRUCTIONS ................................. 7

TROUBLESHOOTING ....................................... 9

SERVICE AND REPAIR ..................................... 10

RETURNING UNITS FOR REPAIR ............................. 10

M170-BGO ............................................... 11

SPECIFICATIONS AND FEATURES ............................ 12

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

M170 Series transmitters are FCC type accepted under the following Parts:

Part 90 (150-172 MHz)
Part 74 (174-216 MHz)

1

GENERAL DESCRIPTION

The M170 Series transmitter is offered in five versions. The standard model is the M170. The
M170-LS, M170-XLR, M170-BGO, and the M170-CTM are modifications of the standard M170.

The M170 and M170-LS transmitters use the microphone cord for the antenna. The M170-XLR uses
the hand-held microphone for the antenna. This feature eliminates the need for the "dangling wire"
antenna found on many transmitters. The walnut body of the M170-CTM is securely attached to a
machined aluminum plate which serves as the antenna ground plane and as mass to absorb vibration.
The M170 Series transmitters use a crystal controlled oscillator and temperature compensation circuitry
to ensure that the transmitter does not drift over time or with age.

To suppress audible noise, a "compandor" noise reduction circuit is used which is compatible with all
Lectrosonics 170 series or 185 series receivers. In addition, the input limiting circuit will absorb 12 dB
of overload without distortion. The audio circuitry is extremely quiet, with low distortion for natural
reproduction of either voice or music. The wide input adjustment range of M170 Series transmitters
allows the use of virtually any microphone on the market and with line level inputs such as tape
recorders or musical instruments.

The M170 Series transmitters operate from a replaceable standard 9 Volt alkaline battery. A precision
battery test circuit continuously monitors the battery voltage. A highly visible LED glows as long as the
battery voltage is high enough to operate the transmitter. A 9 Volt alkaline battery will provide up to 15
hours of operation.

The electret microphone input jack provides 5 Volts DC positive bias for all Lectrosonics electret
microphones. Many other electret microphones may be adapted to the M170 Series by making simple
wiring changes in the microphone connector.

2

M170 VARIATIONS

3