Acquiring and Displaying Waveforms
TDS 684A, TDS 744A, & TDS 784A User Manual 3–15
posttrigger portion. All timing measurements in the waveform record are made
relative to the trigger event. To define the trigger point position:
Press HORIZONTAL MENU ➞ Trigger Position (main) ➞ Set to 10%, Set
to 50%, or Set to 90% (side), or use the general purpose knob or the keypad to
change the value.
Record Length. The number of points that make up the waveform record is
defined by the record length. To set the waveform record length:
1. Press HORIZONTAL MENU ➞ Record Length (main). Select the record
length desired from the side menu. Press –more– to see additional choices.
The available record lengths are as follows:
The TDS 684A Oscilloscope provides record lengths of 500, 1000,
2500, 5000, and 15000 points.
The TDS 700A Oscilloscopes provide record lengths of 500, 1,000,
2,500, 5,000, 15,000, and 50,000 plus, with option 1M, 75,000, 100,000,
130,000, 250,000, and 500,000. Option 1M is available only at the time
of original purchase and is not available for the TDS 684A.
NOTE. TDS 700A Models: Hi Res acquisition mode requires twice the acquisition
memory of other acquisition modes, therefore, the maximum record length
available is 15,000 points for TDS 700A Oscilloscopes without option 1M and
50,000 points with option 1M. Turning Hi Res on switches the setting for record
length accordingly, thereby keeping the oscilloscope from running out of memory.
2. To fit an acquired waveform to the visible screen, regardless of record
length, press HORIZONTAL MENU ➞ Record Length (main). Then
toggle Fit to Screen to ON from the side menu. This feature fits the
waveform automatically much like you could do manually — by turning zoom
mode on and changing the time/division until the waveform fits the screen. To
turn off this feature, toggle Fit to Screen to OFF.
Horizontal Scale. To change the horizontal scale (time per division) numerically
in the menu instead of using the Horizontal SCALE knob:
Press HORIZONTAL MENU ➞ Horiz Scale (main) ➞ Main Scale or
Delayed Scale (side), and use the keypad or the general purpose knob to change
the scale values.