Teledyne LeCroy AP033 - Manual (Page 52)

AP033 Active Differential Probe
46 922260-00 Rev A
H. Adjust Final Attenuator CMRR (C18A)
1. Carefully move the AP033 probe head from the Differential Drive 50 Ohm Termination portion
of the AP033/AP034 Calibration Fixture to the Common Mode Drive 50 Ohm Termination
portion.
2. Remove the BNC cable from the Differential Drive 50 Ohm Termination connector of the
AP033/AP034 Calibration Fixture. Connect one end of the BNC cable to the Common Mode
Drive 50 Ohm Termination connector of the AP033/AP034 Calibration fixture. Connect the
other end of the cable to the female end of a BNC T adapter. Plug the male connector of the
BNC T adapter into the channel 4 input of the oscilloscope. Connect a second BNC cable to the
remaining female connector of the BNC T adapter. Connect the other end of the second BNC
cable to the CAL output BNC connector.
3. Set the oscilloscope to display channel 4, coupling to DC1MΩ vertical scale factor to 200
mV/div and the trigger source to channel 4. Adjust the oscilloscope trigger level as necessary
for a stable display.
4. Set the oscilloscope to display channel 1, vertical scale factor to 10 mV/div. Set the OFFSET to
0.0 mV
5. Adjust Attenuator CMRR (capacitor C18A) for minimum amplitude shift of the displayed
waveform at the trigger point in time. See Figure 10 for adjustment location.
6. Remove all cables, the Calibration Fixture, and the ProBus extender from the AP033 probe.
I. Assemble Probe and Amplifier
1. Carefully slide the large probe tip cover over the probe tip, being careful to engage the input
pins.
2. Snap the small probe cover with the threaded brass insert onto the bottom of the probe.
Engage the probe cable strain relief into the mating area of the cover. Carefully dress the wires
entering the cable to clear the area above the brass insert.
3. Place the lip on the large end of the remaining cover under the mating surface near the probe
tip. Gently press the cover into place. If the cover appears to not close completely, remove it
and again check for adequate clearance between the brass insert and the cable wires.
4. Replace the 5/64” Allen cap screw and tighten.
5. Hold the Logic Board / Amplifier Board assembly in one hand with the Logic board facing up.
Hold the ProBus Interface housing in the other hand with the control side (side with holes for
the buttons) facing up.
6. Align the edges of the Amplifier board with the slots in the center of the inside of the housing.
(The amplifier board is the thicker circuit board and has the BNC connector soldered to it.) Slide