Tektronix P6205, Инструкция по эксплуатации

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Operating Basics
2–2
P6205 Instruction Manual
273 ps
561 ps
Low inductance ground
6 inch ground lead
2 ns/div
50 mV/div
Figure 2–2: Effects of ground lead inductance on waveform fidelity
NOTE
. Ringing and rise time degradation can be masked if the
frequency content of the signal degradation is beyond the bandwidth
of your oscilloscope system.
If you know the self-inductance (L) and capacitance (C) of your
probe and ground lead, use the following equation to determine the
approximate resonant frequency (f
0
) of a parasitic circuit:
f
0
1
2 LC
From this equation, you can see that the desired goal is to lower the
probe and ground lead inductance until the frequency of any
parasitic oscillation is well beyond the desired frequency of the
measurement. The low-inductance ground contact can help reduce
the effects of ground lead inductance.