Digitimer Ltd - DS8R Operator’s Manual
Version 2.0
23
Digitimer Ltd.
Copyright ©2019
Configuring for Front Panel Amplitude Control
To use front panel controls, the lower middle blister button needs to be pressed until the front panel
control icon
is displayed. It should then be possible to adjust the current amplitude with the
primary control dial or Virtual front panel software. If external analogue control is to be used, the
procedure below should be followed.
Configuring for Analogue Voltage Amplitude Control
1.
Ensure that the voltage source is specified to deliver between 0V and +10V.
2.
Make the necessary changes in software or hardware to bring this analogue voltage to 0V.
3.
With the DS8R output disabled, connect the external voltage source to the CONTROL socket
on the DS8R rear panel.
4.
Press the lower middle blister button to the right of the LCD screen to enter the analogue
voltage control mode, displaying the
icon. To zero the input, press and hold the button
until there is an audible beep. During zeroing, the DS8R will display the
icon and
sample the voltage signal at the CONTROL socket, using this level as a reference for the
minimum possible output. This important step ensures that any small DC offsets from the
control device are not translated into a stimulus current
1
when the DS8R is subsequently
triggered.
5.
Once the DS8R gives the audible beep, it should revert to external analogue control mode
displaying the minimum stimulus current of 0mA on the LCD screen and changing the control
mode icon to external analogue control.
6.
Adjust the value of the voltage applied to the CONTROL socket to confirm that the current
amplitude displayed on the DS8R changes as expected. For example, with the Current
Amplitude Limit disabled, a +5V input should display a current amplitude of 500mA and a
voltage of +10V should give 1000mA.
