AC Coupling
A mode that blocks the DC component of a signal but passes the
dynamic (AC) component of the signal. Useful for observing an
AC signal that is normally riding on a DC signal.
Acquisition
The process of sampling signals from input channels, digitizing
the samples, processing the results into data points, and assembling
the data points into a waveform record. The waveform record is
stored in memory.
Active Cursor
The cursor that moves when you adjust the general-purpose knob.
The @ readout on the display shows the position of the active
cursor.
Aliasing
A false representation of a signal due to insufficient sampling
of high frequencies or fast transitions. A condition that occurs
when an oscilloscope digitizes at an effective sampling rate that
is too slow to reproduce the input signal. The waveform displayed
on the oscilloscope may have a lower frequency than the actual
input signal.
Application Module
A small module that you plug in to the front panel to add capabilities
to your oscilloscope. You can use up to four application modules
at one time.
Application Package
An optional package that may include an application module, a
firmware upgrade, and manuals that add capabilities to your oscilloscope.
Attenuation
The degree the amplitude of a signal is reduced when it passes
through an attenuating device such as a probe or attenuator (the
ratio of the input measure to the output measure). For example,
a 10X probe attenuates, or reduces, the input voltage of a signal
by a factor of 10.
Auto Trigger Mode
A trigger mode that causes the oscilloscope to automatically acquire
if it does not detect a valid trigger event.
Autoset
A feature that automatically sets the vertical, horizontal, and
trigger controls to provide a usable display.
Average Acquisition Mode
A mode in which the oscilloscope acquires and displays a waveform
that is the averaged result of several acquisitions. The oscilloscope
acquires data as in the sample mode and then averages it according
to a specified number of averages. Averaging reduces uncorrelated
noise in the displayed signal.
Backlight
The illumination behind the liquid-crystal display.
B Trigger
A second trigger system that works with the main (A) trigger to
capture more complex events. You can use the dual A and B triggers
to trigger after a given wait time or number of events.
Cursors
Paired markers that you can use to make measurements between two
waveform locations. The oscilloscope displays the values (expressed
in volts, time, or frequency) of the position of the active cursor
and the distance between the two cursors.
DC Coupling
A mode that passes both AC and DC signal components to the circuit.
Available for both the trigger system and the vertical system.
Communication Module
A optional module that adds I/0 ports to the oscilloscope.
Delay
A means to delay the acquisition to start long after the trigger
event has occurred. The trigger point does not have to be within
the waveform record when delay is on.
Digital Phosphor
A term that describes the way the digitizing oscilloscope can
simulate the acquisition behavior of an analog oscilloscope. Displayed
points vary in intensity depending on the frequency of their acquisition
and then decay as if the oscilloscope had an analog CRT (cathode
ray tube).
Digital Real Time Digitizing
A digitizing technique that samples the input signal with a sample
frequency of four to five times the oscilloscope bandwidth. Combined
with (sinx)/x interpolation, all frequency components of the input
up to the bandwidth are accurately displayed.
Digitizing
The process of converting a continuous analog signal such as a
waveform to a set of discrete numbers representing the amplitude
of the signal at specific points in time.
Edge Trigger
Triggering that occurs when the oscilloscope detects the source
passing through a specified voltage level in a specified direction
(the trigger slope).
Envelope Acquisition Mode
A mode in which the oscilloscope acquires and displays a waveform
that shows the variation extremes of several acquisitions.
External Trigger
Triggering that occurs when the oscilloscope detects the external
input signal passing through a specified voltage level in a specified
direction (the trigger slope).
Floating Measurements
Voltage measurements where the reference voltage is not earth
ground.
General Purpose Knob
A knob on the front panel that you can use to set parameters,
for example, cursor position. The specific parameter assigned
to the general-purpose knob depends on other selections.
Gray Scale
The waveform display capable of showing points at different intensities,
depending on the frequency of their occurrence. Color "gray
scale" consists of light and dark shades of the color.
Ground (GND) Coupling
Coupling option that disconnects the input signal from the vertical
system.
Ground Lead
The reference lead for an oscilloscope probe.
Ground Wire
A wire that must be connected between the ground terminal and
earth ground when using the oscilloscope with battery power.
Hard Copy
An electronic copy of the display in a format usable by a printer
or plotter.
Holdoff
A specified amount of time that must elapse after a trigger signal
before the trigger circuit will accept another trigger signal.
Holdoff helps ensure a stable display.
Horizontal Bar Cursors
The two horizontal bars that you position to measure the voltage
parameters of a waveform. The oscilloscope displays the value
of the active (movable) cursor with respect to ground and the
voltage value between the bars.
Menu
A set of labels shown in the display to identify the functions
of the bezel buttons. The specific menu contents depend on the
menu button you press.
Normal Trigger Mode
A mode where the oscilloscope does not acquire a waveform record
unless a valid trigger event occurs. It waits for a valid trigger
event before acquiring waveform data.
Peak Detect
An acquisition mode that captures spikes and glitches that may
occur between normal sample points.
Persistence
The decay of waveform points. With persistence turned off, the
points decay quickly. With persistence on, the points decay more
slowly or not at all, depending on the setting.
Pixel
A visible point on the display. The display is 640 pixels wide
by 480 pixels high.
Pretrigger
The specified portion of the waveform record that contains data
acquired before the trigger event.
Preview
The oscilloscope capability to show you what the next acquisition
might look like if you change control settings while acquisition
is stopped or waiting for the next trigger. The new control settings
take effect for the next acquisition. Both horizontal and vertical
preview are available.
QuickMenu
An alternate display presentation that lets you control the most
commonly used functions with the screen buttons. Optional application
packages may have an available QuickMenu display.
Record Length
The specified number of samples in a waveform.
Reference Waveform
A saved waveform selected for display. You can save and display
up to four reference waveforms.
Roll Mode
An acquisition mode useful at slow horizontal scale settings.
Roll mode allows you to view the waveform as it is acquired point-by-point.
The waveform appears to roll across the display.
RS-232
The serial communication port used to connect to a hard-copy device,
computer, controller, or terminal.
Sample Acquisition Mode
A mode in which the oscilloscope creates a record point by saving
the first sample during each acquisition interval. This is the
default mode of the acquisition system.
Sample Interval
The time interval between successive samples in a time base. For
real-time digitizers, the sample interval is the reciprocal of
the sample rate.
Sampling
The process of capturing an analog input, such as a voltage, at
a discrete point in time and holding it constant so that it can
be quantized.
Scope QuickMenu
A built-in QuickMenu that places the most commonly used oscilloscope
controls around the screen. With the Scope QuickMenu, you may
not need to use the main menu system to operate the oscilloscope.
Screen Buttons
The rows of buttons below and to the right of the display that
select items in the menus.
Selected Waveform
The waveform on which all measurements are performed and which
is affected by vertical position and scale adjustments.
Signal Path Compensation (SPC)
The ability of the oscilloscope to minimize the electrical offsets
in the vertical, horizontal, and trigger amplifiers caused by
ambient temperature changes and component aging. You should run
SPC when the ambient temperature varies more than 5' C from the
last SPC or before performing critical measurements.
Single Sequence
A single shot acquisition if Sample or Peak-detect acquisition
mode is selected. A series of N acquisitions if Average or Envelope
acquisition mode is selected (N is the number of averages or envelopes).
Standby (STBY)
The off-like state when the instrument in not in use. Some circuits
are active even while the instrument is in the standby state.
TekProbe Interface
An interface that communicates information between a probe and
the oscilloscope, such as the probe type and its attenuation factor.
The interface also supplies power to active probes.
Tek Secure
A feature that erases all waveform and setup memory locations
(setup memories are replaced with the factory setup). Then it
checks each location to verify erasure. This feature is useful
where the oscilloscope is used to gather security - sensitive
data.
Time Base
The set of parameters that let you define the time and horizontal
axis attributes of a waveform record. The time base determines
when and how long to acquire record points.
Vertical Bar Cursors
The two vertical bars you position to measure the time parameter
of a waveform record. The oscilloscope displays the value of the
active (movable) cursor with respect to trigger and the time value
between the bars.
Video Trigger
Triggering on the sync pulse of a composite video signal.
XY Format
A display format that compares the voltage level of two waveform
records point by point. It is useful for studying phase relationships
between two waveforms.
YT Format
The conventional oscilloscope display format. It shows the voltage
of a waveform record (on the vertical axis) as it varies over
time (on the horizontal axis).
Zoom
The horizontal magnification capability of the oscilloscope. Zoom
is a display function; adjusting zoom does not affect the acquired
waveform.