Practical value of the proximity loss in parallel go and return conductors

When a circuit is formed by two parallel conductors there is a redistribution of current due to the mutual repulsion between the two magnetic fields, a phenomenon which is termed the "proximity effect" and is additional to the ordinary skin effect. The increment of resistance due to this is considerably less than that due to the simple skin effect alone; it is by no means neglegible in larger gauge wire at audiofrequencies or in smaller gauge wire at carrier frequencies. The author gives a formula by which the increment of resistance can be calculated and a series of curves illustrating its application.