PC-Supported 64-Channel DC-EEG Amplifier
For investigation of cortical DC-potential shifts a new, computer based multi-channel amplifier system was developed. Because of high input impedance (>50GΩ), low input bias current (<1pA) and low input capacity (<50pF) the amplifier can be used for epicortical, intracranial and intracellular recordings too. There are no analog outputs, the amplified signals were digitalized by a 16-Bit A/D in each channel of the amplifier, then online digitally filtered and after downsampling stored on the hard disk of a PC. All setups, calibration etc. are done by control of the PC. Other important new features are the capability of self testing (preamplifiers, amplifier setup), of testing electrodes (drift, noise etc.) and a computer controlled electrode application system.
KeywordsSupplementary Motor Area Digital Signal Processor High Input Impedance Main Amplifier Volitional Action
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