A typical calibration curve for this probe is shown below.

The measuring tips of the voltage probe cannot employ a ground connection.
The voltage probe should be well balanced: i.e. both sides of the voltage probe should have the same electrical behavior with respect to the ground reference. The balance of the probe is reflected in the probeís Common Mode Rejection Ratio (CMRR). CMRR is typically expressed in dB and indicates the ratio of the signal out of the probe to a signal applied simultaneously to both probe measuring tips.
The measuring tips of the probe can act as antennas if an electric field is present. Shorter tip length and equal tip lengths, will reduce the electric field pickup, and together with a good CMRR, will minimizes any error in the measured signal.
A loop is formed by the measuring tips of the probe and the load. If a magnetic field is present, it can couple to this loop and induce a signal. The size of the loop affects the pickup: the larger the loop the greater the pickup (CMRR does not affect this pickup). Shorter tip length will reduce the loop size and therefore the pickup.
The FCC-BCP-2 design takes into account all of the above factors.Grounded Load
When measuring the voltage across a load that has one side connected to reference ground, an unbalanced voltage probe is typically used. Such a probe has one measuring tip and a ground connection. If the probe uses a relatively long ground connection lead (pigtail style), this lead can create potential problems:

The ground lead of the probe can act as an antenna if an electric field is present. Shorter lead length will reduce the electric field pickup and will minimize any error in the measured signal.

A loop is formed by the ground lead, the measuring tip of the probe and the load. If a magnetic field is present, it can couple to this loop and induce a signal. The size of the loop affects the pickup: the larger the loop the greater the pickup. Shorter ground lead length will reduce the loop size and therefore the pickup.

The FCC-BCP-2 is supplied with short and equal length tips to minimize the above effects.

Use of the FCC-BCP-2 to Measure Transient (Pulse) Signals
General.
The probe frequency response is quite flat from 2 MHz to 1.8 GHz which allows a nominal scalar correction of ñ34 dB to be applied to correct many raw time domain transient signals. Limitations on applying this scalar are discussed in the following sections.

Risetime Considerations.
The probeís risetime is about 0.2 nsec. Transients being measured that have a risetime less than about 0.1nsec will have an apparent risetime, as measured on a Digital Storage Oscilloscope (DSO), essentially equal to that of the probe. For risetimes of the transient being measured that are near 0.2nsec, the apparent risetime measured on the DSO will about Observed Risetime on DSO = ([(Probe Risetime)2 + (Transient Risetime)2].

For risetimes of the transient being measured that are about 0.4nsec or slower, the apparent risetime measured on the DSO will be within approximately 12% or less of the actual transient risetime.

Late Time Considerations.
If a time domain transient is expressed in terms of its frequency content (via Fourier Transform) it will be seen that, in general, the transient has a DC component. Since the probe cannot pass DC, there may be some late time distortion of the measured transient. This distortion will increase as the width of the transient increases; i.e. the DC component increases with increasing transient width. In general this distortion will be seen as the measured transient width being shorter than it is in actuality. When applying a scalar correction for this late time distortion, the droop of the probe is a useful parameter to effect a reasonable correction factor.

The droop is negligible for pulse widths up to 70 ns.

Transient Amplitude.
For transients having the peak amplitude occurring between approximately 0.2 and 70ns, the transient amplitude can be determined using a scalar correction as follows using the probe calibration provided with the probe by FCC:

Amplitude in Volts = (DSO voltage in Volts) x 10(Probe Cal in dB/20)

Frequency Domain Data Correction.
If complete correction of the test data is required/desired instead of applying a scalar correction factor, it is necessary to perform the data correction in the frequency domain. This is accomplished using the following approach. It is necessary to also have phase versus frequency calibration information available for the probe.
The raw time domain transient recorded on the DSO is transformed into the frequency domain using a Fourier Transform. The resulting frequency domain magnitude data should be in dB. Phase information is typically created during this Transform.

The probe calibration curve expressed in dB (example: Figure 2) is subtracted from the frequency domain calculated in Step 1. For optimum accuracy, the frequencies from the Step 1 calculation should be the same as the frequencies for the probe calibration. This may require interpolation of either the Step 1 data and/or the probe calibration data. Phase data is treated in a similar manner.

Any other instrumentation calibration (example: a fiber optic data link), expressed in dB, could/would be subtracted at this point from the frequency domain calculated in Step 1 in a manner similar to that cited above for the FO Link.

The frequency domain resulting from the Step 2 calculation is then Inverse Fourier Transformed back into the time domain. The resulting time domain waveform is now fully corrected for instrumentation calibrations.

Use of the FCC-BCP-2 to Measure CW Signals
Applying the probe calibration curve to measuring CW signals is relatively straightforward. For the CW frequency being measured, the probe calibration at that frequency is determined from its calibration curve. The measured CW signal is then corrected as follows:

Corrected CW Signal (in dB units) = Measured CW Signal (in dB units) ñ Probe Cal (in dB units)

Or

Corrected CW Signal (in non-dB units) = [Measured CW Signal (in non-dB units)]/[Probe Cal (in non-dB units)].

If the non-dB units are required, the probe calibration needs to be converted from dB. This is accomplished as follows:

Probe Calibration (non-dB) = 10(Probe Calibration in dB/20)