Glossary
Glossary–4
TDS 500B, TDS 600B, & TDS 700A User Manual
Equivalent-time sampling (ET)
TDS 500B and TDS 700A Models Only: A sampling mode in which the
oscilloscope acquires signals over many repetitions of the event. The
TDS 500B and TDS 700A Oscilloscopes use a type of equivalent-time
sampling called random equivalent-time sampling, which uses an internal
clock that runs asynchronously with respect to the input signal and the signal
trigger. The oscilloscope takes samples continuously, independent of the
trigger position, and displays them based on the time difference between the
sample and the trigger. Although the samples are taken sequentially in time,
they are random with respect to the trigger.
Fall time
A measurement of the time it takes for the trailing edge of a pulse to fall
from a HighRef value (typically 90%) to a LowRef value (typically 10%) of
its amplitude.
Frequency
A timing measurement that is the reciprocal of the period. Measured in Hertz
(Hz) where 1 Hz = 1 cycle per second.
Gated Measurements
A feature that lets you limit automated measurements to a specified portion
of the waveform. You define the area of interest using the vertical cursors.
General purpose knob
The large front-panel knob with an indentation. You can use it to change the
value of the assigned parameter.
Glitch positive trigger
Triggering occurs if the oscilloscope detects positive spike widths less than
the specified glitch time.
Glitch negative trigger
Triggering occurs if the oscilloscope detects negative spike widths less than
the specified glitch time.
Glitch either trigger
Triggering occurs if the oscilloscope detects either positive or negative spike
widths less than the specified glitch time.
GPIB (General Purpose Interface Bus)
An interconnection bus and protocol that allows you to connect multiple
instruments in a network under the control of a controller. Also known as
IEEE 488 bus. It transfers data with eight parallel data lines, five control
lines, and three handshake lines.
Graticule
A grid on the display screen that creates the horizontal and vertical axes. You
can use it to visually measure waveform parameters.