Odd Path Adjustment - LeCroy WaveSurfer 400 Series Service Manual

Setting Timebase ⇒ 1ns/div, RIS

6.9.3.7 Odd path adjustment

6.9.3.7.1 Auto-adjustment
Adjustment method
6.9.3.7.2 Manual adjustment
Adjustment standard Delay sdev 7ps
Setting CH1 ⇒ DC 50Ω 10mV/div
Timebase ⇒ RIS, 1ns/div
Trigger ⇒ Delay: 0ns (center of display screen)
Adjustment method
(1) Input a high-speed pulse signal to CH1 and input an approximate
1kHz signal to CH2.
(2) In the "Measure" menu, set "Delay – C1." Click "Statistics" to turn
"On" this function.
(1) In the "Trigger" menu, select "Edge Trigger" and set "Trigger on –
C1" and "Holdoff by – None."
(2) In the "Trigger" menu, select "Smart Trigger - Qualify" and set
"After – C2" and "Holdoff by – Events 1#."
(3) In the "Trigger" menu, switch "Edge Trigger" and "Smart Trigger."
In the "Maintenance1" menu, adjust "Other Adjustment –
DelayQual" such that the "mean" difference for each measured value
becomes ±100ps or less.
(4) Click "Save to HW" to save to the EEPROM.
(1) Run "Automatic Adjustment - OddPathCorrection" in the
"Maintenance1" menu.
(2) After the auto-adjustment is completed, click "Save to HW" to save
to the EEPROM.
(1) Input a high-speed pulse signal and set the trigger level to roughly the
midpoint of the amplitude.
(2) In the "Measure" menu, select "Delay."
(3) In the "Maintenance1" menu, adjust "OddPath" such that the
measured value "sdev" is minimized.
(4) After the adjustment is completed, click "Save to HW" to save to the
EEPROM.
Maintenance 6-43