Scope / Multimeter
Operation and Controls
23
To turn peak detect on and off, select the
Peak Detect
icon.
Filter
Using the filter feature can minimize or smooth out signal spikes and fast variations,
depending on which function is its used with.
Filter - Lab Scope
Using the filter with the lab scope, smooths out fast spikes, which helps to provide
a good balance between noise suppression and signal integrity.
Using the filter is useful when working with scales of 5 volts and below, as the lower
the voltage scale, the more likely noise can occur.
Example:
Using the filter is helpful when testing components such as, an O2
sensor (1or 2 volt scale), or when performing a throttle position (TP) sensor
sweep test (5 volt scale).
In addition, the filter is also helpful for low amp probe tests, as a low voltage scale
is used to measure the output of the probe (due to the conversion factors of the
probe).
Example:
For a probe with a conversion factor of 100 mV/A connected to a 2
amp load, the scope uses a 200 mV scale to measure the output of the probe.
The scope converts the measured output to 2 amps for display on the screen.
Filter - GMM
Using the filter with the GMM, the filter minimizes noise by ignoring or smoothing
out fast signal spikes.
•
For a direct measurement test, such as volts, amps, or pressure, the filter
minimizes the display of very fast spikes by averaging the sampled data when
filter is active.
•
For a calculated measurement test, such as frequency, pulse width, dwell, or
duty cycle, extremely fast spikes (20 µS and faster) from sources like the
ignition system are ignored when filter is active.
To turn the filter on and off, select the
Filter
icon.
Invert
The Invert feature is used to switch signal polarity, so the trace appears upside
down (inverted) on the screen. This is typically used when measuring amperage
using the low amp probe, or high-voltage signals like, secondary ignition.
Example:
A signal that normally rises from 0 to +5 volts, if inverted would show
falling
from 0 to –5 volts.
To turn inversion on/off, select the
Invert
icon.
Coupling AC
Coupling AC subtracts the average value of a signal so that small variations can be
displayed in the waveform. This is accomplished by blocking the direct current (DC)
portions of a signal in order to amplify (show) the alternating current (AC) portions
of the signal, without driving the trace off of the screen.
Using coupling AC can be helpful when testing and diagnosing alternator ripple or
fuel pump amperage, by allowing you to see any abnormal small variations or
events.
To turn coupling AC on and off, select the
Coupling AC
icon.
Peak Detect Icons
On (Sampling maximized)
Off (Sampling not maximized)
Filter Icons
On (Interference is suppressed)
Off (Interference is not suppressed)
Invert Icons
On (Polarity is inverted)
Off (Polarity is not inverted)
Coupling AC Icons
On (DC signal portion blocked)
Off (DC signal portion not blocked)
Содержание Vantage Legend
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