11) Although these effects are already well established in the literature for low-frequency current, there are no studies showing the direct effect of medium frequency current in the induction of large or polyarticular muscle relaxation.
Among these forms of medium frequency electrical stimulation, interferential current (IFC) is a device frequently used clinically, with a higher tissue penetration and less discomfort when compared to low-frequency current.
Many products contain nonlinear switched-mode power supplies that contribute to the contamination of the power lines, and variable frequency drive systems are prevalent, providing another source of low-frequency current
Years ago, audio circuit board designers learned to avoid this problem by gapping the return plane in order to control the low-frequency current return paths and keep the analog currents away from the digital currents.
Our students are given a design problem requiring them to protect sensitive analog components (usually audio amplifiers or phase-locked loop oscillators) from digital circuitry by gapping the return plane in such a way that the low-frequency currents are isolated and the high-frequency currents are not impeded.
Copper-clad has the advantage of somewhat greater stiffness to withstand repeated insertion forces, while solid copper has the advantage of being better able to carry a low-frequency current
to power a remote-control device, such as a camera in the baby's room.
But the membranes that enclose cells will impede movement of a low-frequency current
through those cells.
An arc causes momentary high-frequency current spikes that ride on the low-frequency current
TENS is the use of low-frequency currents
with rectangular impulses of certain duration; analgesia is achieved with electric stimulation of neuron inhibitory system of the spinal cord last horn, via descending paths mediated by opiates (endorphins and enkephalins) [3, 9].
High-power, low-frequency currents
are sometimes found in relay and control circuits.
are blocked by capacitances within the motor, such as those between varnished windings and the motor frame.