D. adjust ÷10 attenuator cmrr (r7) – Teledyne LeCroy AP033 User Manual
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AP033 Active Differential Probe
42
922260-00 Rev A
D. Adjust ÷10 Attenuator CMRR (R7)
1. Keep the BNC cable attached to the probe end of the ProBus extension cable. Attach a 50Ω
BNC Through Terminator on the other end of the BNC cable. Attach the male end of the 50Ω
terminator to channel 3 on the oscilloscope. The oscilloscope end of the ProBus extension
cable should remain connected to channel 1 of the oscilloscope although there is no signal
cable attached.
2. In the Channel 1 “COUPLING” menu, set AP033 Atten/Gain to Manual, Probe Atten to /10 and
Probe Gain to X10.
3. Connect a BNC cable from the output of the Function Generator to the Channel 2 input of the
oscilloscope.
4. Connect a second BNC cable from the Function Generator SYNC OUT to the external trigger
input of the oscilloscope.
5. Set the Function Generator waveform to Sine and the frequency to 70 Hz.
6. Set the oscilloscope as follows:
Display: Channel 2
Channel 1 VOLTS/DIV: 2 mV/div
Channel 2 VOLTS/DIV: 5 V/div
Channel 3 VOLTS/DIV: 2 mV/div
Channel 2 Coupling: DC1MΩ
Channel 3 Coupling: AC 1MÙ
Trigger on: EXT10
cplg EXT10: DC
TIME/DIV: 10 ms/div
Acquisition Mode: NORMAL
7. Adjust the trigger level for a stable display.
8. Set the Function Generator output voltage to 20 Vp-p as displayed on the oscilloscope.
9. Disconnect the output cable of the function generator from the channel 2 input of the
oscilloscope and reconnect it to the Common Mode Drive No Termination connector of the
AP033/AP034 Calibration Fixture.
10. Carefully align the four pins that correspond to the Common Mode Drive No Termination
portion of the AP033/AP034 Calibration Fixture with the input receptacles in the AP033 probe
head. Press the probe into the fixture to fully engage the pins.
11. Set the oscilloscope to display channel 3. The waveform is the common mode signal. Turn the
offset as necessary to keep the trace on screen. Turn on Math Channel A. Press MATH SETUP,
then REDEFINE A. Set the A Math type to Average, Avg Type to Continuous, with 1:15