Teledyne LeCroy AP033 - Manual (Page 45)

Operator’s Manual
922260-00 Rev A 39
Procedure
A. Adjust Preliminary Probe DC Balance (R36)
1. From the oscilloscope’s front panel, select channel 1. Set the AP033 Atten/Gain to Manual, the
Probe Atten to /10, and the Probe Gain to X10.
2. If necessary, set the probe offset to 0.000 V.
3. Connect one end of a BNC cable to the probe end of the ProBus Extension Cable. Attach the
precision 50 Ω terminator to the opposite end of the BNC cable.
4. Insert the banana plugs of the precision 50 Ω terminator into the input terminals of the DMM.
5. Insert the two pin shorting plug into the socket on the Logic board. Use the two holes closest to
the probe cable. (See Figure 6).
Figure 7, AP033 Logic Board
6. To enter the Cal Mode, push any one of the four buttons that protrude through holes in the Logic
board. Entry into Cal Mode is confirmed by the absence of an audible “click” when you push the
button.
7. Adjust DC Bal (R36) on the probe tip (Figure 7) to obtain a DMM reading of 0 V ±10 mV.
NOTE: This voltage may not be stable because of air currents near the probe. The average
voltage should be 0 V ±10 mV.