Teledyne LeCroy CP500 - Manual (Page 11)

Instruction Manual
922176-00 Rev A 5
Operation with a Teledyne LeCroy Oscilloscope
The probe can be controlled through the Vertical Setup dialog for the channel to which the probe is
connected.
Turning the VOLTS/DIV knob will control the oscilloscope’s scale factor to give full dynamic range.
The CP500 probe dialog (a tab behind the channel setup dialog) allows for the selection of the probe’s
coupling (DC, Grounded or AC), AUTO ZERO, DEGAUSS PROBE and Probe BWL functions, limiting the
system bandwidth to 20 MHz or maximum bandwidth (BWL Off).
Bandwidth Limit
The CP500 is capable of switching the bandwidth from Full (maximum bandwidth) to 20 MHz by
selecting the bandwidth adjustment on the CP500 dialog.
AC Coupling
DC, Ground or AC coupling can be selected through the CP500 dialog. AC coupling occurs at the input of
the oscilloscope and not at the probe input. When using the CP500 in the AC coupling mode and
measuring AC signals with a DC component, care must be taken to assure that the dynamic range of the
probe will not be exceeded. There will be no warning if the dynamic range is exceeded. If clipping of the
waveform occurs, check to see if the operating range of the probe has been exceeded. This can be done
by changing the coupling back to DC and setting the scale factor to the maximum Amp/Div.
Auto Zero
The CP500 incorporates an Auto Zero function to remove the DC offset from the current probe. Auto
Zero must be invoked by the user. After several minutes of warm-up, or when the probe is exposed to a
large shift in ambient temperature, some DC offset drift may occur. To initiate an Auto Zero cycle, touch
the CP500 tab (behind the Channel Vertical Setup dialog), then touch AUTO ZERO.
Degauss Probe
If the probe has been magnetized by external magnetic field or by excessive input, the core can be
demagnetized by opening the CP500 dialog and touching DEGAUSS PROBE.
Prior to use, the CP500 probe should be degaussed to eliminate any residual magnetization from the
probe core. Residual magnetism in the core is a major cause of measurement errors when used at high
sensitivities. The demagnetizing process takes about 5 seconds and should always be performed before
taking a measurement.
Without clamping the probe around a conductor, slide the opening lever to close and lock the probe,
and touch DEGAUSS PROBE twice.