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Section 5: Measurement options
Model 6517B Electrometer Reference Manual
5-10
6517B-901-01 Rev. C / August 2015
Figure 59: Typical PREAMP OUT connections
Figure 60: Typical PREAMP OUT connections - equivalent circuits
Using external feedback
The external feedback function provides a means to extend the capabilities of the Model 6517B
Electrometer to such uses as logarithmic currents, non-decade current ranges, as well as non-
standard coulombs ranges. The following paragraphs discuss the basic electrometer input circuitry
and methods to implement these functions.