There’s plenty of truth to that old saw, especially when a switch-mode power supply from the 1940s still ... to conduct large currents. In this circuit, the Thyratrons are used as half-wave ...

This man-made interference is known as “QRM” in ham parlance, and it has become almost intolerable of late, as poorly engineered switch-mode power supplies have become more common. But hams ...

A computer power supply converts AC ... Power supplies known as "switching" power supplies are commonly used. Their name is derived from the type of circuit used to change the voltage.