Tektronix THS3014, Руководство пользователя

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Operating Basics
Attach the Reference
Leads Correctly
If you are using all four of the instrument channels, you must attach the probe
reference lead for each channel directly to your circuit. These attachments
are required because the channels are electrically isolated; they do not share a
common chassis connection. Use the shortest possible reference lead with each
probe to maintain good signal
fi delity.
The probe reference lead presents a higher capacitive load to the circuit-under-test
than the probe tip. When taking a
fl oating measurement between two nodes of a
circuit, attach the probe reference lead to the lowest impedance or least dynamic
of the two nodes.
Parasitic capacitance between probes, instrument, and environment. Parasitic
capacitance can occur between the input references and the environment. For this
reason, you should connect the references to a system ground or another stable
voltage. If the reference of an input is connected to a high speed and/or high
voltage signal, you should be aware of parasitic capacitance. (See Figure 9.)
Figure 9: Parasitic capacitance between probes, instrument, and environment
THS3000 Series Oscilloscopes User Manual 21