The high voltage isolated preamplifier is built to cope with large common mode voltage of ±1kV and to resist to 1kV of a differential transient voltage. The signal is split in two paths:

Low frequency DC to 50kHz channel preamplifier x1, x10 or x100, opto-isolator and low-pass filter

High frequency 5kHz to 15Mhz channel with preamplifier x4 and transformer isolation

An acquisition via DAQmx (opto-isolated ch) and NI-scope (transfo-isolated) allows for the measurement of both signals with different clock rates. A subtle analysis tool can recombine the 2 signals and restore a DC to 15MHz signal.