Digitimer Ltd - DS8R Operator’s Manual
Version 2.0
22
Digitimer Ltd.
Copyright ©2019
Polarity Mode
The DS8R can output pulses in positive, negative or alternating polarity. Pressing the upper middle
blister button to the right of the LCD screen cycles between these three modes and changes the icon
associated with this control button.
Normal (Positive) Polarity
Reverse (Negative)
Polarity
Alternating Polarity
Amplitude Control Mode
The current amplitude is manually controlled via the DS8R front panel dial or Virtual front panel
software. It is also possible to control pulse amplitude through use of an analogue voltage input
applied to the rear of the DS8R via the CONTROL socket. Briefly pressing the lower middle blister
button cycles through the operating modes, sequentially displaying the two icons below.
Front Panel Amplitude Control Mode (hardware or
software).
Analogue Voltage Control Mode.
The analogue voltage mode allows a connected computer data acquisition interface/software to
vary the stimulus amplitude throughout a protocol without manual operator intervention. The
CONTROL input accepts a voltage of 0V to +10V which is used to proportionately scale the stimulus
output over the range of 0mA to 1000mA. For example, if the analogue voltage input is +2.5V, the
stimulator will deliver a 250mA stimulus upon the next trigger. However, if the Current Amplitude
Limit is enabled, this voltage input is re-scaled to match the set output range. If the Current
Amplitude Limit is set to 10mA, +10V at the input will result in a 10mA stimulus, rather than
1000mA.
