Starting Electronics

Diodes

II

Filter

tips

Although we've managed to obtain a full-wave rectified

d.c. load voltage we still have the problem that this volt-

age

is not too steady (ideally we would like a fixed d.c.

voltage

which doesn't vary at all). We can reduce the

up-and-down

variability of the waves by adding a capaci-

tor to the circuit

output.

If you remember, a capacitor

stores charges — so we can use it to average out the

variation in level of the full-wave rectified d.c. voltage.

Figure

7.12 shows the idea and a possible resultant wave-

form.

This process is referred to as

smoothing

and a

capacitor

used to this

effect

is a

smoothing

capacitor.

Sometime