The Refa system of TMSI is integrated in IMAGO Record. The definition of channel names is essential for recording. All channels you want to record must have a name define via an instrument. Calibration Coefficient The calibration coefficient is used to convert recorded voltages to a physical unit. Each channel has an input for a calibration factor. If e.g. 1V = 10 uV, the number 10 u will be used to convert the recorded voltage into the physical unit V and will be stored as physical unit of the channel. For TMSI, the calibration coefficient has an additional meaning. TMSI is working with 32Bit numbers which generate large files. IMAGO uses 16Bit numbers. To be able to do so, the desired amplitude range needs to be defined here. If e.g. EMGs are measured, the expected amplitude range is 1 mV or lower. For EEG signals, the range could be 10 uV. Entering 1 mV will amplify the calculated input voltage signal by 1000 (1 / 1m) so that the signal is comparable in size with the auxiliary signals also recorded with TMSI. If the calibration coefficient is selected too big, this has an impact on the resolution written to file. The resolution might be shown different on screen since the screen display works with a floating number while the file is written with a converted 16Bit integer number. If the calibration coefficient is selected too small, the amplified signal might clip. Clipping is shown while recording. The offset of each channel can be adjusted. The offset changes immediately and can be viewed in the Calibration window. The offset is input in Volts. All channels are filtered to remove the floating artifacts. The cutoff frequency can be defined. Filtering TMSI does not provide any signal processing. To remove the offset of the signals while recording, a bandpass filter is provided. Use the Highpass filter to remove the offset. You can go below 0,01Hz to remove the offset without affecting the signal quality. Filtering is done for the first 128 channels. The Auxiliary channels are not filtered. Unipolar vs. bipolar Normally all channels are recorded as unipolar channels. You can define channel pairs which are subtracted to view the resulting bipolar signal while recording. This is necessary to see the quality of the signals. Since it is useful to have a complete set of unipolar channels to process e.g. with Matlab, the bipolar channels are added to the end of the list of unipolar channels. E.g. you want to define channel 10 as a bipolar signal using channel 5 as reference. Switch from unipolar to bipolar in channel 10 and select the reference as 5. While recording the TMSI signals, IMAGO Record calculates the bipolar channel 10 - 5 and adds it to the end of the list. Before the subtraction both channels are filtered. The cutoff frequency of the filter can be defined in the instrument. Bipolar channels are added to the end of the unipolar channel list. Since it is possible to deselect some channels, this would lead to constantly changing position of the bipolar channels. Therefore, the bipolar channels are starting from the top. The top channel is the channel defined in Extras -> Options as Number of channels of first A/D converter. If e.g. 64 channels need to be recorded and in addition 5 bipolar channels are added, Nr of channels of first A/D converter can be defined as 70. The first bipolar channel gets channel number 70, the second gets channel number 69, ... Using additional channels from an other A/D converter You can record additional channels from a second A/D converter. The range of the TMSI channels is defined by Extras -> Options. The Number of channels for the first A/D converter defines the maximum channels received from TMSI. If you want to use an additional A/D converter, select the device number in Options -> Extras (Name of second A/D converter) and define your additional channels within the TMSI instrument, using the channels starting with (number of channels of first A/D converter + 1) Specialities concerning TMSI TMSI supports a lot of channels. To help you generate a setup without defining each channel separately, IMAGO Record has implemented some special features. Press Clear to reset all entries and only select the first 16 channels. Afterwards, select the maximum channel you want to record. E.g. if you want to use a pad with 64 electrodes, select channel 64. You find channel 64 with the vertical slider. If the vertical slider shows channel 64, the channel is located in the upper line. After defining the maximum channel, you have the possibility after each change of the channel activation or calibration to copy the entry to all selected channels. Also the channel names are filled automatically. Please note that the number of channels for the first A/D converter needs to match the number of channels you select for the TMSI amplifier. Select Extras -> Options to change the value. Impedance View In the impedance view the impedance for all 136 available channels are shown. You can use this view to test the quality of contact. Press Save to save the result in a spreadsheet file. Before you have selected channels (before the first recording), all possible channels are shown. If you have selected a subset of the available channels, only the subset is shown.