natus XLTEK Protektor32, Instructions For Use Manual

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Instructions for Use XLTEK Protektor32
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E) Channels Tab
To specify the electrodes you will be using in each channel:
1. Click the Channels tab. --Each pair of electrodes that is added here will use one of the available
channels on the headbox. -- Click Append to add a new channel to the Inputs table.
2. To choose an active electrode for the channel, right-click the cell in the Active column, and select
an active electrode from the menu displayed.
3. To choose a reference electrode for the channel, right-click the cell in the Reference column and
select an electrode location from the menu. Repeat Steps 3 and 4 until you have all of the
required inputs for your montage.
To invert waveforms – e.g., Left Erbs point to Right Erb’s point, and then Right Erb’s point to
Left Erb’s point -- so that they will deflect upwards on the active window. To do so, you must
add another input channel.
4. The amplifier gain is set in the Input Range column of the Inputs tab. To set the same input
range for all of the input channels, right-click the Input
Range
column heading and select a value.
To set different gains for different channel types, right-click a cell in the Input Range column and
select a value.
For most EP recordings, an amplifier gain of ±50 - ±100 µV is generally acceptable.
If too much noise is present, however, an amplifier input range of ±500 µV is advisable for
EMG recordings.
5. Reject Threshold is the level at which the input (amplifier) rejects unwanted signals (e.g., from
Bovie knife and bipolar cauterizers). To set the Reject Threshold , right-click the column heading
or individual cells and select a value from the menu. Note that you may select a level below the
Input Range
, but not above. To adjust your
Reject Threshold
up, you must increase your
Input
Range .
6. To enable your speaker for EMG sound, right-click cells in the Sound column and select Off, 25,
50, 75 or 100% as desired.