Twists
In some electrical cables wires may be twisted
together. For some configurations this may be an effective method for
reducing or for reducing
pickup. Differential current in adjacent half-twists may produce fields
that partially cancel. Similarly, differential current induced in one
half-twist by an externally coupled field may be partially cancelled by current
induced in the adjacent half-twist.
Enter the number of full twists per meter.
Tech Note - Twisting
When
the wires of a transmission line are twisted together, current induced on
adjacent half-twists tends to cancel, so long as the length of the twist is
short compared to the wavelength of the incident field. This has the
desirable effect of reducing the induced current at the terminations. As
frequency increases, and the length of the twists is no longer short compared to
wavelength, the effect diminishes because current induced on adjacent half
twists is no longer 180 degrees out of phase. More:
 Angle
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