II.
Data Capture
DISCUSSION
Set up one data capture for 0.655 seconds. The capture should be triggered when
the sine wave is applied. The data capture should be a total of 0.655 seconds .
Of the total capture time, 0.131 seconds of the capture should show what the
signal looked like before the sine wave was applied.
ACTION
HOW TO
Enter data capture setup
[SYS] [SETUP DATA CAPTURE]
Select capture of all channels
[SET CHANNELS]
Keep Channels 1 through 4.
[EVENTS]
Toggle off to not capture event markers.
[EXIT]
Set sample rate to 25 kHz
[SET SAMPLE RATE]
The number of samples per second. In general, select
at least ten times the frequency of your signal or the frequency of any changes in
signal. Turn encoder wheel until sample rate is 25 kHz.
Set record size to 64 Ks
[SET RECORD SIZE]
The Dash 4u will give you the amount of time that data
will be captured based on the record size and the sample rate. This is shown
under the duration field. Turn encoder wheel until record size is 64 Ks.
Set trigger window to 20%
[SET TRIGGER Win.]
Placing the trigger at any point other than the start of
the capture window will allow for pre-trigger data to be captured. Turn encoder
wheel until trigger window is 20%.
Set capture for one record
[SET OPERATION]
You can capture one record or re-arm for more captures.
Turn encoder wheel to single capture.
Be sure auto triggering is OFF
[AUTOTRIG]
If auto triggering is ON, toggle to OFF. If toggled ON, auto-
triggering is designed to immediately capture data once the Dash 4u is armed.
Enter trigger setup
[SYS] [SETUP TRIGGER]
Enable waveform triggering
[WAVEFORM]
Waveform should be toggled to ON position.
Set up the logic for triggering
[TOGGLE LOGIC]
Insure that OR logic is chosen.
Pick waveform(s) for triggering
Turn encoder wheel so that only Channel #1 is selected.
Set up the level for triggering
[SETUP WAVEFORM] [SET CHANNEL]
Turn encoder wheel to select
Channel #1.
[SET TYPE / CLASS]
Use wheel to select window - outside for type of
trigger.
[<<FIELD>>]
Turn encoder wheel to set the High level to be 65%.
[<<FIELD>>]
Turn encoder wheel to set the Low level to be 35%.
Run the chart
[RUN / HALT]
Arm for capture
[ARM]
This key is located near the encoder wheel. The Dash 4u is now
recording pre-trigger data, waiting for the trigger.
