Probe calibrators

Calibration of oscilloscopes often neglects an important part of the measurement chain – the probe. To correctly evaluate probes and dividers, a test signal of high bandwidth and sufficient amplitude is required. Such a signal is quite often not available. Therefore, problems in high frequency behavior or a voltage dependent change of the divider ratio (VCR effect) may remain undiscovered.

The probe calibrators of KHT series generate fast pulses of high bandwidth and help to close a gap in the calibration chain.

Most common oscilloscopes supply a rectangular voltage of max. 10 V for adjustment and calibration of the probes. Adjustment of this calibration source is not possible unless the case is opened. Above all, this voltage is not sufficient enough to check probes with divider ratios of 10:1 or higher. These are often designed for input voltages up to several hundred volts or more.

Test and adjustment should be performed using a signal of sufficient voltage. The rise time of this signal must be low enough to evaluate the dynamic properties of the whole system consisting of oscilloscopes and probes.