Lectrosonics MM400a - Manual - Manual (Page 3)

Frequency Agile UHF Miniature Belt-Pack Transmitter
Thank you for selecting the Lectrosonics MM400A miniature transmitter. The unique design provides several distinct
features for professional applications:
• Outstanding RF operating range
• Superb audio quality
• Ultra-lightweght, corrosion resistant housing
• Watertight seals for use in wet environments
• Programmble emulation modes for maximum versatility
The Digital Hybrid Wireless TM design (US Patent Pending) combines 24-bit digital audio with analog FM techniques
to provide the operating range of the finest analog wireless systems and the audio quality of a pure digital system.
The 100 mW RF output power extends operating range, and DSP controlled, dual-envelope limiter cleanly handles
input peaks to allow higher gain settings. This combination maximizes operating range and the signal to noise ratio
of the system.
The input provides 6 VDC of bias voltage for use with modern electret lavalier microphones. Multi-color LEDs are
provided on the control panel to make input gain adjustments quick and accurate, without having to view the receiver.
The battery compartment accepts AA alkaline, lithium or NiMH batteries. The antenna is a detachable, locking ¼
wavelength flexible bronze cable that connects to a 50 Ohm SMA port on the transmitter.
The MM400A is machined from a solid aluminum block to provide an extremely ightweight package with the rugged­
ness needed in extreme environments. Input jacks and controls are O-ring sealed for watertight protection in wet
environments. A special non-corrosive finish (same as is used on NASA space vehicles) resists salt water exposure
and perspiration in extreme environments.
The DSP-based design offers backward compatibility with a handful of earlier analog designs, such as the Lec­
trosonics 100 and 200 Series receivers, and some other brands of analog wireless receivers. The operating mode
(compatibility mode) can be selected with a sequence of frequency switch settings and battery insertions to cycle the
power on and off. Only the MM400A transmitter is covered in this manual. Companion receivers are covered in
separate manuals.
TABLE OF CONTENTS
GENERAL TECHNICAL DESCRIPTION ........................................................................ 4
GENERAL ................................................................................................................... 4
DIGITAL HYBRID WIRELESS TM TECHNOLOGY* ................................................... 4
NO PRE-EMPHASIS/DE-EMPHASIS ......................................................................... 5
LOW FREQUENCY ROLL-OFF .................................................................................. 5
INPUT LIMITER .......................................................................................................... 5
PILOT TONE SQUELCH ............................................................................................. 5
WIDE-BAND DEVIATION ............................................................................................ 5
BATTERY LIFE ........................................................................................................... 5
FREQUENCY AGILITY ............................................................................................... 5
CIRCULATOR/ISOLATOR ........................................................................................... 5
CONTROLS AND FUNCTIONS ...................................................................................... 6
POWER ON/OFF SWITCH ......................................................................................... 6
POWER LED .............................................................................................................. 6
MIC JACK ................................................................................................................... 6
AUDIO LEVEL ............................................................................................................. 7
MODULATION LEDS .................................................................................................. 7
FREQUENCY ADJUST ............................................................................................... 7
ANTENNA ................................................................................................................... 7
THE BELT CLIP .......................................................................................................... 7
MICROPHONE RF Bypassing ........................................................................................ 8
INPUT JACK WIRING ...................................................................................................... 8
BATTERY INSTALLATION ............................................................................................... 8
OPERATING INSTRUCTIONS ........................................................................................ 9
SELECTING THE COMPATIBLITY MODE .................................................................. 9
ADJUSTING THE TRANSMITTER FREQUENCY .................................................... 10
ATTACHING A MICROPHONE AND ADJUSTING GAIN .......................................... 10
OPERATING NOTES ..................................................................................................... 11
REPLACEMENT PARTS AND ACCESSORIES ........................................................... 11
TROUBLESHOOTING ................................................................................................... 12
SPECIFICATIONS AND FEATURES ............................................................................ 13
SERVICE AND REPAIR ................................................................................................. 14
RETURNING UNITS FOR REPAIR ............................................................................... 14
LIMITED ONE YEAR WARRANTY ................................................................................ 16
Rio Rancho, NM – USA 3