Tektronix P6243, Инструкция по эксплуатации

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Operating Basics
P6243 Instructions
11
R
source
V
source
Probe C
in
1 pF
Probe R
in
1 M
Ω
L
gl
(Ground Lead)
Figure 3: Ground Lead Equivalent Circuit
You can determine if ground lead effects may be a problem in your
application if you know the inductance (L) of the ground lead and
input capacitance (C) of the probe. Calculate the approximate
resonant frequency (f
0
) at which this parasitic circuit will resonate
with the following formula:
f
0
=
1
2 π LC
The preceding equation shows that reducing the ground lead
inductance will raise the resonant frequency. If your measurements
are affected by ringing, your goal is to lower the inductance of your
ground path until the resulting resonant frequency is well above the
frequency of your measurements.