Keithley 2182, User Manual, Page: 151 / 339

Stepping and Scanning 9-3
Step/Scan overview
The Model 2182 can step or scan its two input channels or be used with external scanner cards
installed in switching mainframes such as Models 707, 7001, and 7002. The following
paragraphs summarize the various aspects of stepping/scanning using the Model 2182.
NOTE Step and Scan operations are illustrated by trigger models (see “ Front panel trigger
models ” in this section).
Internal Stepping/Scanning (Channels 1 and 2)
When stepping or scanning the two input channels of the Model 2182, Channel 2 is selected
(measured) first and then Channel 1 is selected (measured). For every step/scan cycle, Channel 2
is measured once, and Channel 1 can be measured from 1 to 1023 times. Measured readings are
automatically stored in the buffer.
External Stepping/Scanning
When using external switching cards, the switching mainframe controls the opening and
closing of individual channels. Up to 800 external channels can be stepped/scanned and
measured by Channel 1 of the Model 2182 (Channel 2 cannot be used for external stepping or
scanning). Measured readings are automatically stored in the buffer.
To synchronize Model 2182 measurements with external channel closures, connect the
Trigger Link lines of the nanovoltmeter and switching mainframe. Refer to Section 7
( Triggering ) for details and an example on using external triggering.
NOTE Channel annunciators do not turn on during an external step or scan.