Using The 10:1 Probe For High Frequency Measurements; Probe Attenuation; Probe Adjustment - Fluke 125 User Manual

Using the 10:1 Probe for High Frequency
Measurements.
The test tool is supplied with a model VP40 10:1 Probe.
Use of this Probe is recommended when you measure
high frequency signals in circuits with a high impedance.
The loading of the circuit by a 10:1 Probe is much lower
than that of a 1:1 Shielded Test Lead.
Probe attenuation and probe adjustment must be
observed when using a 10:1 Probe.

Probe Attenuation.

The Probe attenuates the signal 10 times. Proceed as
follows to adapt the Test Tool's voltage readout to this
attenuation. The example below is for a Probe connected
to input A:
The Input A MEASUREMENTS
menu and a F1....F4 button bar
pops up.
Open the INPUT... menu
Highlight PROBE: SELECT...

Using the 10:1 Probe for High Frequency Measurements.

Open the PROBE on A menu
Highlight 10:1 V
Accept the probe type. The menu
will be closed.
Observe that the 10 times attenuation of the Probe is
compensated in the voltage readout.

Probe Adjustment.

The Probe of model VP40 such as supplied with the Test
Tool is always adapted correctly to its inputs: high
frequency adjustment is not necessary.
Other 10:1 Probes however must be adjusted for optimal
High Frequency performance. How to adjust these Probes
is explained in Chapter 8 under 'Using and Adjusting 10:1
Scope Probes'.
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Scope/Meter Mode
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