Operator's Manual
DS7A - Constant Current Stimulator
Installation & Initial Check
Before installation and use of the DS7A, ensure that this manual has been read and understood.
Before use with a patient, the DS7A should be tested in its operational location using a simulated situation.
If required, due to the associated EMG-system, the Trigger parameter selection switches may need
adjustment, as described in this manual.
The DS7A should be situated near and within easy reach of the Recordist using the EMG-system to which
the DS7A will be attached.
The DS7A should be stood on a sturdy flat surface where the front panel can easily be viewed.
Check that the Mains Voltage Selection and Fuses are correct for the local supply.
With the power switched off, connect the power cord between the DS7A and an appropriate outlet.
Connect a Trigger Cable between the DS7A and the EMG-system in the manner you have chosen, as
described in this manual.
With the Output Enable switch (top RH corner) downward [disabled], switch on the power to the DS7A.
Check that the POWER indicator is illuminated, and the FAULT indicator illuminates for approximately 2
seconds.
Check that the TRIGGER indicator illuminates, for less than a second, each time the Trigger button is
pressed.
Check that the stimulus polarity control operates correctly in the normal, reverse and alternating polarity
modes.
If the Triggering is set for the DS7A to trigger the EMG-system - check that when the Trigger button is
pressed the EMG-system acquires a sweep of data.
- or -
If the Triggering is set for the DS7A to be triggered by the EMG-system - check that when the EMG-
System sends a trigger pulse the DS7A TRIGGER indicator flashes.
To check that the DS7A and EMG-system are synchronised using the stimulus artefact -
- connect two patient stimulating electrode leads into the DS7A Output sockets and lay them on some
insulating material. Connected together the “electrodes” to form a “short-circuit” and arrange the leads NOT
to run parallel to each other.
- connect two recording leads into the Input of one channel of an EMG-system and lay them on the same
insulating material. Do NOT connect these together, or allow them to touch the “Stimulating Electrodes”;
- arrange the “Recording Electrode” leads so that they each run parallel to one of the “Stimulating Electrode”
leads;
- with the DS7A Output Enabled, a suitable stimulus intensity (start low at 5mA, and increase if necessary)
and EMG-system settings, the recorder should be able to record the artefact from the stimulator operating.
Check that this is at the time expected, which will usually be at the very start of the recording sweep.
Digitimer Ltd.
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Copyright © 2014
File Ref: N:\Docs\Company\Manuals\DS7A\Issue-14\DS7A-iss14.odt
Last Revised: February 1, 2017
DS7A
EMG-headbox
