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Appendix A
A.2 Starting Calibration
PCI-1720 cards use eight variable resistors (VRs), two for each channel,
which allow you to calibrate each of the card’s four output channels. The
following information outlines the function of each VR. Refer to the illus-
tration shown below for the locations of the VRs.
Figure A.1: PCI-1720U VR assignment
VR1 Channel 0’s full scale (gain) adjustment.
VR2 Channel 1’s full scale (gain) adjustment.
VR3 Channel 2’s full scale (gain) adjustment.
VR4 Channel 3’s full scale (gain) adjustment.
VR5 Channel 0’s offset adjustment.
VR6 Channel 1’s offset adjustment.
VR7 Channel 2’s offset adjustment.
VR8 Channel 3’s offset adjustment.
You should use a precision voltmeter/ammeter to obtain accurate read-
ings when calibrating the card. Standard procedures for performing a cal-
ibration are given below.
