error signal from the integrator 310 is connected to the input of a high voltage amplifier 312 having a gain of about 200 the output of the high voltage amplifier 312 is connected to the power supply common not shown of the floating input section 320 therefore the probe assembly 302 and the entire floating input section ride on this changing output when the output of the high voltage amplifier 312 equals the voltage on the test surface 350 the output of the probe 302 is zero and the integrator 310 holds a constant value thereby maintaining the proper high voltage amplifier output any change in voltage on the test surface 350 will produce a reaction from the circuit to effect a change toward a zero output from the probe 302 the output of the high voltage amplifier 312 contains the desired information this output of the high voltage amplifier 312 must be conditioned to be usable and compatible with other devices thus the power supply signal conditioning circuitry section 322 includes power supplies 326 a voltage level converter 314 output amplifiers 316 and peak detection circuitry 318 the output of the high voltage amplifier 312 is connected to a continuous monitor comprising voltage level converter 314 and output amplifiers 316 acting as an inverting amplifier with a gain of 0 008 the gain is set by the voltage level converter 314 which acts as a high impedance precision voltage divider having a total resistance of approximately 10 megohms and output amplifiers 316 for a 100 volt change on the high voltage amplifier 312 there will be a corresponding change of 0 8 volts on the continuous monitor output the continuous monitor includes an adjustable.