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14.6 Practical Oscillator Circuits
Basically, then, an oscillator consists of an oscillatory circuit (L and
C in Fig. 14.6) and a maintaining amplifier (the rest of Fig. 14.6).
Owing largely to the necessity for feeding the amplifier with d.c,
practical oscillator circuits usually look very different from
Fig. 14.6, and it is often quite difficult to see that in principle they
are the same.
A resistive potential divider is rarely used, for it adds to the losses.
And it is quite unnecessary; the oscillatory circuit can be made to act
as its own potential divider. One method is to 'tap' the coil, as in
Fig. 14.7. (To show no bias in favou ...