Glossary - PICO picoscope 3204 User Manual

Glossary

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Glossary
AC/DC switch
To switch from AC coupling to DC coupling, or vice versa, select AC or DC from the
control on the oscilloscope toolbar of the PicoScope software application. The AC setting
filters out any DC component of the input signal, and is suitable for viewing small AC
signals superimposed on a DC or slowly-changing offset. In this mode you can measure
the peak-to-peak amplitude of an AC signal but not its absolute value. Use the DC setting
for measuring the absolute value of a signal.
Analog bandwidth
The input frequency at which the measured signal amplitude is 3 dB below its true value.
Block mode
A sampling mode in which the computer prompts the oscilloscope to collect a block of
data into its internal memory before stopping the oscilloscope and transferring the whole
block into computer memory. This mode of operation is effective when the input signal
being sampled is high frequency. Note: To avoid aliasing effects, the maximum input
frequency must be less than half the sampling rate.
Buffer size
The size of the oscilloscope buffer memory, measured in samples. The buffer memory is
used by the oscilloscope to store data temporarily. This allows the oscilloscope to sample
data independently of the speed at which it can transfer data to the computer.
Device Manager
Device Manager is a Windows applet that displays the current hardware configuration of
your computer. On Windows 98 or Windows ME, right click on 'My Computer' and choose
the 'Device Manager' tab. On Windows 2000 or XP, right-click on 'My Computer,' choose
'Properties', then click the 'Hardware' tab and the 'Device Manager' button.
Driver
A software application that controls a piece of hardware. The driver for the PicoScope
3000 Series PC Oscilloscopes is supplied in the form of a 32 bit Windows DLL. This is
used by the PicoScope and PicoLog software to control the oscilloscopes.
ETS
Equivalent Time Sampling. ETS constructs a picture of a repetitive signal by accumulating
information over many similar wave cycles. This means the oscilloscope can capture fast
repeating signals that have a higher frequency than the maximum sampling rate. Note:
ETS should not be used for one-shot or non-repetitive signals.
External trigger
This is the BNC socket marked E on the PicoScope 3204/5/6 PC Oscilloscopes. It can be
used to start a data collection run but cannot be used to record data. As it shares the
same connector as the signal generator output, these two functions cannot be used at the
same time. It is possible, however, to use the output from the signal generator as a
trigger.
Maximum sampling rate
A figure indicating the maximum number of samples the oscilloscope can acquire per
second. Maximum sample rates are usually given in MS/s (megasamples per second) or
GS/s (gigasamples per second.) The higher the sampling capability of the oscilloscope,
the more accurate the representation of the high-frequency details in a fast signal.
PS3000044 1.4
Copyright 2005 Pico Technology Limited. All rights reserved.