Digitimer Ltd - DS8R Operator’s Manual
Version 2.0
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Digitimer Ltd.
Copyright ©2019
8.
Output Status Indicators.
9.
Pulse Measurements Panel.
10.
Icon showing that the audible Out of Compliance alert is muted.
11.
Current Amplitude Limit setting (shown as disabled i.e. 1000mA).
User Configurable DS8R Settings
The sections below provide further information relating to each of the user defined DS8R settings.
Most settings (including analogue control auto zero level) persist following power-cycling, so if the
DS8R is powered off and back on again, the settings present at power off will remain at start up. The
only exception is the role of the secondary control dial, which always reverts to Pulse Duration
control upon start up.
Adjustments to settings made via the front panel, virtual front panel and CONTROL input are all
reflected in the front panel display of the DS8R and the virtual front panel software.
Current Amplitude
With front panel amplitude control, the current amplitude is adjusted using the primary (amplitude)
control dial. As the dial is turned clockwise, the current will increase in 0.1mA steps between 0mA
and 1000mA.
Note that in analogue voltage control mode (see below), the primary control dial and virtual front
panel software amplitude controls will have no effect as current amplitude changes can only be
made via the rear panel analogue voltage input.
Current Amplitude Limit
As the DS8R has the capability of delivering currents from 0.1mA to 1000mA, an optional Current
Amplitude Limit is provided, which allows the operator to set an absolute maximum current that can
be delivered by the stimulator. For instance, users who are stimulating below 10mA can set the limit
to 10mA in order to prevent inadvertent stimulation at higher values.
The limit can be set in mA increments between 10mA and 999mA. It is set by pressing and holding
the Current Amplitude Control for 4s at the desired maximum current level. The limit is reset
(reverting to a 1000mA maximum) by repeating this procedure. It can also be set and re-set from
within the DS8R Front Panel Software. The value displayed in green numerals, to the right of the set
current value, confirms what amplitude the limit is set to, showing 1000 when disabled.
Note that with the limit enabled, it is not possible to deliver a stimulus in excess of that set by the
limit. This applies to ALL methods of stimulus amplitude control (front panel, virtual front panel,
analogue voltage input and software API).
Pulse Duration
The DS8R is capable of delivering stimulus pulses of 50µs to 2000µs in duration, with a minimum
increment of 10µs.
