MM400B
Lectrosonics
MM400B
Lectrosonic MM400B Transmitter
The Digital Hybrid Wireless™ design 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 the 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 bias voltage for use with modern electret lavaliere microphones. Multi-color LEDs make input gain adjustments quick and accurate, without having to view the receiver. The battery compartment accepts AA alkaline, lithium or NiMH batteries, and a detachable antenna ¼ wavelength flexible cable connects to a watertight 50 Ω SMA port on the transmitter.
The MM400B is machined from a solid aluminum block to provide the lightweight, rugged package needed in extreme environments without compromising functionality. Input jacks and controls are O-ring sealed for watertight protection in wet environments. A special noncorrosive 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 Lectrosonics 100 and 200 Series receivers, and other brands of analog wireless receivers. Compatibility Modes are easily selected with a sequence of frequency switch settings and cycling the unit’s power.
The input provides 6 VDC bias voltage for use with modern electret lavaliere microphones. Multi-color LEDs make input gain adjustments quick and accurate, without having to view the receiver. The battery compartment accepts AA alkaline, lithium or NiMH batteries, and a detachable antenna ¼ wavelength flexible cable connects to a watertight 50 Ω SMA port on the transmitter.
The MM400B is machined from a solid aluminum block to provide the lightweight, rugged package needed in extreme environments without compromising functionality. Input jacks and controls are O-ring sealed for watertight protection in wet environments. A special noncorrosive 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 Lectrosonics 100 and 200 Series receivers, and other brands of analog wireless receivers. Compatibility Modes are easily selected with a sequence of frequency switch settings and cycling the unit’s power.
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Manufacturer Specs
Operating frequencies:
Block 21 537.600 - 563.100
Block 22 563.200 - 588.700
Block 23 588.800 - 607.900 and 614.100 - 614.300
Block 24 614.400 - 639.900
Block 25 640.000 - 665.500
Block 26 665.600 - 691.100
Block 27 691.200 - 716.700
Block 28 716.800 - 742.300
Block 29 742.400 - 767.900
Frequency selection: 256 frequencies in 100 kHz steps
RF Power output: 100 mW (nominal)
Pilot tone: 25 to 32 kHz; 5 kHz deviation (in 400 Series Mode)
Frequency stability: ± 0.002%
Deviation: ± 75 kHz max. (in 400 Series Mode)
Spurious radiation: 60 dB below carrier
Equivalent input noise: –118 dBV, A-weighted
Input level: Nominal 2 mV to 300 mV, before limiting.
Greater than 1.5V maximum, with limiting.
Input impedance: 2 kOhm
Input limiter: Soft limiter, >30 dB range
Gain control range: 43 dB; semi-log rotary control
Modulation indicators: Dual bicolor LEDs indicate modulation of –20, -10, 0, +10 dB referenced to full modulation.
Low frequency roll-off: –12 dB/octave; 70 Hz
Signal to Noise Ratio (dB) (overall system, 400 Series mode):
Note: The dual envelope “soft” limiter provides exceptionally good handling of transients using variable attack and release time constants. Once activated, the limiter compresses 30+ dB of transmitter input range into 4.5 dB of receiver output range, thus reducing the measured figure for SNR without limiting by 4.5 dB.
Total Harmonic Distortion: 0.2% typical (400 Series mode)
Audio Input Jack: 2.5 mm Microjack (matches Switchcraft 850 Microplug)
Antenna: Detachable, flexible galvanized steel with SMA connector. (50 Ohm antenna port also allows connection to test equipment.)
Battery: 1.5 Volt AA lithium recommended
Battery Life: 1.75 hours (alkaline); over 6 hours (lithium);
3.5 hours (2200 mAhr) NiMH
Emission Designator: 180KF3E
Block 21 537.600 - 563.100
Block 22 563.200 - 588.700
Block 23 588.800 - 607.900 and 614.100 - 614.300
Block 24 614.400 - 639.900
Block 25 640.000 - 665.500
Block 26 665.600 - 691.100
Block 27 691.200 - 716.700
Block 28 716.800 - 742.300
Block 29 742.400 - 767.900
Frequency selection: 256 frequencies in 100 kHz steps
RF Power output: 100 mW (nominal)
Pilot tone: 25 to 32 kHz; 5 kHz deviation (in 400 Series Mode)
Frequency stability: ± 0.002%
Deviation: ± 75 kHz max. (in 400 Series Mode)
Spurious radiation: 60 dB below carrier
Equivalent input noise: –118 dBV, A-weighted
Input level: Nominal 2 mV to 300 mV, before limiting.
Greater than 1.5V maximum, with limiting.
Input impedance: 2 kOhm
Input limiter: Soft limiter, >30 dB range
Gain control range: 43 dB; semi-log rotary control
Modulation indicators: Dual bicolor LEDs indicate modulation of –20, -10, 0, +10 dB referenced to full modulation.
Low frequency roll-off: –12 dB/octave; 70 Hz
Signal to Noise Ratio (dB) (overall system, 400 Series mode):
| SmartNR | No Limiting | W/ Limiting |
| OFF | 103.5 | 108.5 |
| NORMAL | 107 | 111.5 |
| FULL | 108.5 | 113 |
Note: The dual envelope “soft” limiter provides exceptionally good handling of transients using variable attack and release time constants. Once activated, the limiter compresses 30+ dB of transmitter input range into 4.5 dB of receiver output range, thus reducing the measured figure for SNR without limiting by 4.5 dB.
Total Harmonic Distortion: 0.2% typical (400 Series mode)
Audio Input Jack: 2.5 mm Microjack (matches Switchcraft 850 Microplug)
Antenna: Detachable, flexible galvanized steel with SMA connector. (50 Ohm antenna port also allows connection to test equipment.)
Battery: 1.5 Volt AA lithium recommended
Battery Life: 1.75 hours (alkaline); over 6 hours (lithium);
3.5 hours (2200 mAhr) NiMH
Emission Designator: 180KF3E