Giga-tronics 80350A, Operation & Maintenance Manual

Page: 38 / 110

Series 8035XA Peak Power Sensors
2-14 Manual 21568, Rev. F, March 2008
2.3.9 Measuring 3 dB Pulse Width
Pulse width and other pulse timing parameters can be measured using the REL key and the
sample delay offset control (see Figure 2-16).
1. Preset the delay offset to 0 nS.
2. Set the sample delay equal to about half the pulse width.
3. Press [REL] to set the 0.0 dB reference level (100% for Watts display).
4. Set the sample delay to a position on the rising edge of the pulse. Increment or decrement the
sample delay value until the power level display reads approximately -3.00 dBr.
5. Remember or write down the sample delay value.
6. Press [MENU], and use the up/down arrow keys to display SETUP MENU. Press [ENTER].
Select PEAK SNSR SETUP, then select the current triggering method (INT or EXT). When
DLY Offset appears, set the offset value to the same time value from Step 4. This sets the 3 dB
down time point to a 0.0 ns reference position.
7. Press [ENTER] to return to the measurement display.
8. Set the sample delay to a position on the falling edge of the pulse. Increment or decrement the
sample delay value until the display again reads approximately -3.00 dBr.
The sample delay currently displayed is the signal’s 3 dB pulse width.
Figure 2-16: Using SD to Measure a 3 dB Pulse Width
100% Reference Level
3 dB down (50%)
3 dB down (50%)
Sample Delay
Offset
Total Delay
Trigger Level
Sample Delay = Pulse Width
t
t
=