Teledyne LeCroy AP033 - Manual (Page 28)

AP033 Active Differential Probe
22 922260-00 Rev A
Matching Procedure for ÷10 Plugs
The ÷ 10 Plug-on attenuator provided as a standard accessory with the AP033 is calibrated to match
the specific probe it was shipped with. Individual probes will have small variations in parasitic
capacitance within the input circuits. To obtain maximum common mode rejection performance,
the attenuators are calibrated to match a specific probe during the manufacturing process. In order
to preserve the maximum Common Mode Rejection, do not interchange external attenuators
between probes.
The Plug-on AC coupling adapter is not matched to a specific probe and, therefore, does not need
to be matched. If the

÷

Plug-on attenuators become accidentally mixed between probes, you
can use the procedure listed below to restore the compensation match. This adjustment does not
affect any of the parameters in the warranted specifications. Therefore, the required test
equipment does not need to be calibrated.
NOTE: The AP033 and AP033 Active Differential Probes have different input capacitance. The

10
Plug-on attenuator supplied with model AP033 cannot be properly adjusted for use with model
AP033. Make sure that the attenuator is marked “AP033” before attempting this procedure.
Equipment Required
Test Oscilloscope
The oscilloscope must support ProBus. With a non-ProBus oscilloscope, use the ADPPS power
supply.
Signal Source
Low frequency square wave: Frequency 50 Hz to 5 kHz, Amplitude 1 V to 10 V. The output
waveform must have a square corner and flat top with minimum overshoot suitable for adjusting
compensation. The generator should have trigger output, or use a BNC Tee connector and separate
BNC cable from the output to provide the trigger signal for the test oscilloscope.
Interconnect Cable
This is for connecting the output of the signal source to the probe. A BNC cable and a pair of small
alligator clips or “lead grabber” adapter (Pomona #3788) may be used. 0.025 in. (0.635 mm)
Square Pins (3 required). The pins from the header supplied in the probe accessory kit are suitable.
Tools
Flat bladed screwdriver, 0.040 in. (1 mm) wide
Adjustment Tool: 0.025 in. (0.635 mm) square head