Tektronix P6209, Инструкция по эксплуатации

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Operating Basics
14
P6209 4 GHz Probe Instruction Manual
Use the DC offset adjustment to maintain the probe within its
dynamic range. The nominal offset adjustment range of the P6209 is
±
5.0 VDC. For example: to offset a +2 VDC level in a circuit, set the
offset to +2 V.
NOTE
. The probe can tolerate input voltages of
±
30 V (
≤
5 minutes)
without damage; however, the linearity error specification does not
apply to input voltages outside the linear dynamic range of the
probe. See Figure 1 on page 10.
Ground Lead Length
When you are probing a circuit, you should always use as short a
ground lead as possible between the probe head and circuit ground.
The series inductance added by the probe tip and ground lead can
result in a resonant circuit; this circuit may cause parasitic ringing
within the bandwidth of your oscilloscope. When you touch your
probe tip to a circuit element, you are introducing a new resistance,
capacitance, and inductance into the circuit. Refer to Figure 3.
R
source
V
source
Probe C
in
1 pF
Probe R
in
20 K
Ω
L
gl
(Ground Lead)
Figure 3: Ground lead equivalent circuit
Ringing and rise time degradation can be masked if the frequency
content of the signal degradation is beyond the bandwidth of the
oscilloscope.