5-5
IM DL850E-01EN
• Before you turn on the DL850E/DL850EV, connect the external hard disk to the DL850E/DL850EV, and
turn on the external hard disk. If you connect a hard disk or turn it on after you turn on the DL850E/
DL850EV, the hard disk will not be detected. Also, when the external hard disk is on, do not disconnect its
cable.
• Hard disk recording cannot be performed when the record length is less than 1 Mpoint.
• Hard disk recording cannot be performed when the action mode is on.
• When you enable hard disk recording, the trigger mode is automatically set to On Start.
• When hard disk recording is enabled, you cannot use an external clock as the time base.
• During hard disk recording, only starting and stopping of hard disk recording, the zoom display settings,
and the protect feature are valid.
• The upper limit of the time axis zoom factor during hard disk recording is the maximum zoom factor that
can be displayed during hard disk recording.
• During hard disk recording, you cannot display history waveforms, loaded waveforms, or computed
waveforms.
• You can perform the following operations on data that has been recorded to a hard disk. You cannot use
the history feature.
Cursor measurement, automated measurement of waveform parameters (up to 100 Mpoint), waveform
zooming, computation and printing
• During hard disk recording, the DL850E/DL850EV may respond more slowly to operations.
• The maximum number of files that can be saved to a single folder is 1000.
• Do not connect USB storage media to the DL850E/DL850EV during hard disk recording or when you will
start hard disk recording.
Time Base (Time Base)
Under the initial settings, the DL850E/DL850EV samples the measured signals using the clock signal produced
by its internal time-base circuit (internal clock). You can also use an external clock signal to control sampling.
One data sample is stored to the acquisition memory at every pulse in the external clock signal. The external
clock input is useful when you want to monitor the waveform using a clock signal that is in sync with the signal
being measured.
Apply the external clock signal to the external-clock input terminal (EXT CLK IN) on the left panel. For the
specifications of the external-clock input terminal, see the
getting started guide
, IM DL850E-03EN.
Int
The internal clock signal is used as the time base (the TIME/DIV time axis setting is valid).
Ext
An external clock signal is used as the time base (the TIME/DIV time axis setting is invalid).
5 Waveform Acquisition