Features

• High-quality amplifier/encoder for neurofeedback applications.
• USB-powered
• Five-year manufacturer's warranty against all defects.
• Includes standard built-in impedance-checking circuitry.
• Excellent customer service and support

Specifications

1. Channels: 4 EEG channels + 3 Auxiliary channels (0 to +2.0 volts dc)
2. Input Impedance: > 5 Meg Ohms differential at the electrode jacks > 100 Gig Ohms at the amplifier inputs
3. CMR: > 100 dB
4. Noise: < 1.0 uV p-p referred to input
5. Preamp Gain: Software Selectable: 50, 100, 500 microvolts p-p full scale
6. Anti-Alias Filter: 4th Order Butterworth at 55Hz
7. Bandpass: 0.5 Hz to 55 Hz
8. Notch Filter: > 50dB rejection at 60Hz / 50Hz or Notch OFF
9. Impedance Test: An electrode test command is sent under software control to produce a simultaneous test of all electrodes.
10. Calibration: An internal calibration system is based on a crystal controlled DDS (direct digital synthesizer) with amplitude adjustment. Under software control, the calibrator can generate any frequency from 000.01 Hz up to 999.99 Hz with an accuracy of +/- .002 Hz. Amplitudes from 0 up to 100 microvolts may be selected.
11. A2D Resolution: 16 bits
12. Sample Rate: 256 samples/sec.
13. Aux Inputs: The Alpha400 amplifier provides three AUX input channels. Inputs to these channels must be isolated from the patient. Input voltage is: 0.0VDC to 2.50VDC.
14. Computer Interface: Isolated USB
15. Power: All Alpha400 power is derived directly from the USB cable.
16. Isolation: Medical grade digital isolation per UL 1577 Component Recognition Program.

Each isolator is fully tested with 3000V rms for 1 second, and 2500V rms for 1 minute. Internal isolated dc-dc converter rated at 6000 VAC isolation.