A consideration for electrical nonlinear distortion voltage caused by 2D type bridge with very low frequency current

It must need to take off the cause of nonlinearity if someone needs a good resistor. The 3
^rd
harmonic distortion voltages of three types of resistors were measured. In the next stage, the 3
^rd
harmonic voltage is tested using by a bridge made on a printed circuit board (PCB) occurs current constriction effectively. It is very simple structure without contact barriers to consider the cause of nonlinear distortion. It is obvious that the short bridge causes the high distortion voltage. It seems that heat oscillation for power dissipation and propagation of one cycle of AC current from both bride edges to wide areas of PCB would cause the 3
^rd
harmonic distortion voltage. In this study, further testing with very low frequency current is superposed to check the AC heating effect is prevented by the low frequency current.