Tektronix passive high voltage probe tektronix p5122 the tektronix p5122 is a passive high voltage probe that is ideal for heavy duty high performance measurements of voltages up to 1000v in many applications it is important to be able to isolate the measurement from earth ground and also to isolate the common voltage between channelsthe p5122 coupled with the tps2000 and ths3000 series digital storage oscilloscopes deliver both the isolation for the measurement from earth ground and ful