MA-411

The MA-411 EMG preamplifier has been designed for ease of use and reliability, and provides superb performance in day to day use, as well as in the hands of the researcher or first time user. Unlike many competing EMG preamplifiers, Motion Lab Systems preamplifiers incorporate both radio frequency interference (RFI) filters and electrostatic discharge (ESD) protection circuitry resulting in an extraordinarily reliable EMG preamplifier that can be used in almost any environment, For example a clean EMG signal can be obtained if the subject is holding a mobile phone and making a phone call; note that TMS stimulation may disrupt the phone call, but the EMG signal will be instantly detected. A surface preamplifier with a x20 gain, designed for EMG signals. Featuring a differential input design, the design of the Motion Lab Systems EMG preamplifiers enables researchers to produce high-quality, low-noise EMG data from subjects under the most adverse conditions (e.g. on treadmills, using mobile phones etc.) with minimal skin preparation or subsequent signal processing.

Features

• Direct EMG pre-amplification at the skin surface provides the highest myoelectric signal quality for accurate, reliable EMG signal detection and completly eliminates cable motion artifact.
• Internal RFI and ESD protection prevents radio frequency interference and static damage.
• The low-impedance output of the preamplifier eliminates cable noise and cable motion artifacts without requiring any additional signal processing within the preamplifier.
• An integral ground reference plane provides immunity to electromagnetic environmental noise.
• All signal and power conductors in the preamplifier cable are enclosed inside an independent, isolated shield to eliminate interference from AC power-lines and other sources of interference.
• All subject contacts are corrosion-free, medical grade stainless steel for maximal signal flow.
• Constructed using biocompatible housing and sensor materials to prevent allergic reactions.
• Each unit is professionally built using high precision surface-mount instrumentation components for optimal EMG performance.
• The preamplifier can be easily disinfected and cleaned with any medical grade alcohol wipes.

Mechanical Specifications

• Sensor Contacts - two 12 mm disks
• Reference Contact - 13 x 3mm bar separating the sensors
• Inter-electrode distance - 17 mm
• Contact Material - Medical Grade Stainless Steel
• Body Size - 38mm x 19mm x 8mm.
• Weight - 10 grams (excluding lead and connector).
• Cable Length - 1.4 meters (55 inches).
• Temperature Range - 0 to 40 degrees C.

Electrical Specifications

• Gain at 1 kHz x20 ±1%
• Input Impedance > 100,000,000 ohms.
• Noise < 1.2uV RMS
• CMRR. > 100 dB at 65Hz.
• Input Protection - RFI and ESD protected.
• Signal Bandwidth - 20Hz to 3,500Hz (-3dB).
• Power supply range ±5 Volts to ±15 Volts
• Power consumption 2.4mA per supply throughout voltage range.

Connector Options

• MA-411-000 - no connector.
• MA-411-001 - Harwin - 6 pin female.
• MA-411-002 - Binder - 4 pin male.
• MA-411-003 - LEMO - 4 pin male.

This preamplifier is available with a DC or AC coupled output - the 002 and 003 connector options are AC coupled (100nF), while the 000 and 001 options are DC coupled. Also available with HyperTac D series connectors for use the Therapeutics Unlimited EMG systems.