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voltage is taken off. This normally happens to a rectifier during half
of every cycle. The usefulness of the gate is that it enables forward
current to be prevented during any desired proportion of the other
half-cycle and so enables the rectified output to be controlled, a
facility used, for example, to control the brightness of mains-driven
lamps.
27.5 Rectifier Circuits
There are various ways in which rectifiers can be connected in power
unit circuits, and one of the simplest is indicated in Fig. 27.4a. A
transformer Τ is shown for stepping the mains voltage up or down as
required, and a single rectifier—the symbol denotes any type—i ...