Multichannel Systems MC_Rack Manual - Manual (Page 59)

Step by Step Tutorial
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The appropriate “Amplifier Gain” factor of the MEA2100-System will automatically be entered.
The “Input Voltage Range of Data Acquisition Board” divided by the gain is the “Signal Voltage
Range”, the maximum size of signals you can record before they get clipped. Please adjust the
"Input Voltage Range of Data Acquisition Board" according to the expected size of your signals.
It is advisable to select the input voltage range as small as possible, to ensure an optimal A/D
resolution of the analog input signals.
The “Sampling Frequency” should also be selected as low as possible, depending on the signals
you like to measure, to minimize data file size.
If several instances of MC_Rack are used to operate the MEA2100-System, for example with
a MEA2100-HS2x60 headstage or two MEA2100-HS120 headstages, each instance of MC_Rack
operates independently; you can define the “Input Voltage Range of Data Acquisition Board”
and the “Sampling Frequency” for each instance of MC_Rack individually.
Hardware Filter Settings
While the MEA2100-System in principle can measure DC signals, this is for most purposes
very impractical, as the baseline would constantly drift. Therefore the system is equipped with
software configured hardware filters. By default, a second order high pass filter with a cut
off frequency of 1 Hz is used to prevent a baseline drift. The upper cut off frequency is 3.3 kHz.
Additionally you can use the software filters of MC_Rack, if necessary.
Note: It is possible to change the settings of these filters without modification of firmware
or hardware via the add on program ”MEA2100 Configuration”.
Setting up the Internal Stimulus Generator of the MEA2100-System
The headstage of the MEA2100-System is equipped with an integrated 3-channel stimulus
generator. The three stimulation channels operate independently. If two instances of MC_Rack
are used to operate one headstage, each MC_Rack instance works completely independent,
so three stimulation channels are available for each instance. If four instances of MC_Rack are
used to operate two headstages, for example MEA2100-HS2x60, each MC_Rack instance works
independent respectively, so twelve stimulation channels are available, three for each instance.
It is possible to choose between current or voltage controlled stimulation, and any electrode can
be selected for stimulation. The control functions for electrode selection and definition of the
stimulation parameters are integrated into MC_Rack, you do not need any additional software.
However, it is possible to import stimulation patterns generated in MC_Stimulus II as ASCII data.
Add the internal stimulus generator to your rack: Click menu “Edit” and choose "Add MEA2100
Stimulator".