The Picotest P2102A Probe is 50 ohm transmission line 4-point probe (2 signal lines and 2 ground). This precision probe supports a variety of measurements including impedance (2-port series and shunt-through), transient step load, ripple, noise, TDT/TDR, PCB power rail, VRM (Voltage Regulator Module), clock jitter, and non-invasive stability (NISM). It has significant advantages over active probes and other types of passive probes.