MM400A
Lectrosonics
MM400A
Lectrosonics MM400A 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 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 on the control panel 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 Ω SMA port on the transmitter.
The MM400A is machined from a solid aluminum block to provide an extremely ightweight package with the ruggedness 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 Lectrosonics 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.
The input provides 6 VDC of bias voltage for use with modern electret lavalier microphones. Multi-color LEDs on the control panel 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 Ω SMA port on the transmitter.
The MM400A is machined from a solid aluminum block to provide an extremely ightweight package with the ruggedness 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 Lectrosonics 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.
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Manufacturer Specs
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 kΩ
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
Controls: Front panel knob adjusts audio gain.
Rotary switches on bottom panel adjust transmitter frequency.
Audio Frequency Response: 70 Hz to 20 kHz, +/-1dB (The audio is deliberately rolled off at 70 Hz using a
12 dB/octave filter. This filter cannot be disabled.)
Signal to Noise Ratio (dB, overall system, 400 Series mode)
Total Harmonic Distortion: 0.2% typical (400 Series mode)
Audio Input Jack: 2.5 mm Microjack (matches Switchcraft 850 Microplug)
Antenna: Detachable, flexible bronze wire supplied. 50 Ω port allows connection to test equipment.
Battery: 1.5 Volt AA lithium recommended
Battery Life: 2 hours (alkaline); 4.5 hours (lithium); NiMH: 3.5 hours
Emission Designator: 180KF3E
Specifications subject to change without notice.
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 kΩ
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
Controls: Front panel knob adjusts audio gain.
Rotary switches on bottom panel adjust transmitter frequency.
Audio Frequency Response: 70 Hz to 20 kHz, +/-1dB (The audio is deliberately rolled off at 70 Hz using a
12 dB/octave filter. This filter cannot be disabled.)
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 |
Total Harmonic Distortion: 0.2% typical (400 Series mode)
Audio Input Jack: 2.5 mm Microjack (matches Switchcraft 850 Microplug)
Antenna: Detachable, flexible bronze wire supplied. 50 Ω port allows connection to test equipment.
Battery: 1.5 Volt AA lithium recommended
Battery Life: 2 hours (alkaline); 4.5 hours (lithium); NiMH: 3.5 hours
Emission Designator: 180KF3E
Specifications subject to change without notice.