Tektronix Keithley 2601B-PULSE - Page 99

Model 2601B-PULSE System SourceMeter® Instrument User's Manual Section 4: Operation
2601B-PULSE-900-01 Rev. A August 2021 4-9
Figure 44: Coaxial connectors for 2601B-PULSE
All connections are electrically isolated from chassis ground.
The rear panel of the 2601B-PULSE provides a low-noise chassis ground banana jack that can be
used as a common signal ground point for the SENSE and FORCE LOs. This low-noise signal ground
banana jack is connected to the chassis through a frequency variable resistor (FVR). The FVR,
shown in the figure below, is used to isolate the SMU from high frequencies that may be present on
the chassis of the 2601B-PULSE. As frequencies on the chassis increase, the resistance of the FVR
increases to dampen their effects. For dc to 60 Hz, the FVR is a virtual short (zero Ω).
The chassis screw terminal is connected to the metal chassis of the 2601B-PULSE.
Figure 45: Chassis ground banana jack
1 Low-noise chassis ground banana jack
2 Signal ground
3 Frequency variable resistor (FVR)
4 Chassis
5 Chassis screw
Do not use the chassis as a ground point for signal connections. High frequencies on the chassis of
the 2601B-PULSE may result in higher noise. The chassis should only be used as a safety shield.
Use the chassis screw for connections to the chassis of the 2601B-PULSE.