Agilent Technologies 54657A, User Manual

Page: 46 / 89

To create a mask template using Automask
A mask template contains two limit lines: minimum and maximum.
Automask allows you to easily generate a mask with tolerances from a
displayed waveform on the screen.
1
Connect a known good signal to the oscilloscope.
2
Set up the oscilloscope with the settings that are required to test the
signal.
3
Press ±
.
4
Press the
Mask Test
softkey.
5
Toggle the
Use Mask
softkey to select the desired mask number
(1 or 2).
6
Press the Define Mask Automask softkey.
7
Press the Tolerance softkey, then turn the knob closest to the
Cursors
key to set the tolerance.
Pressing the softkey increases the tolerance value by 0.2%.
8
Press the
Create Mask
softkey to create the mask with the specified
tolerance.
Tolerance Operating Hint
The tolerance used in Automask is expressed as a percentage of the full-scale
time and voltage of the lowest number of all active channels. It does not
represent the tolerance of the actual size of the input signal. To specify the
tolerance as a percentage of the actual size of the input signal requires some
additional calculations.
For example, a signal of 1 volt peak-to-peak is tested at a vertical sensitivity of
500 mV/div. The full-scale voltage equals the volts/div times the number of
full-scale divisions (500 mV * 8 = 4 V). To specify a 4% tolerance on a 1 V
peak-to-peak signal requires a 40 mV tolerance, but to specify a 40 mV tolerance
on a full-scale voltage of 4 volts requires a 1% tolerance. Therefore, a 1%
tolerance should be specified to generate the mask template.
Operating the Measurement/Storage Module
To create a mask template using Automask
2–30