Chapter 30: Oscillators
MULTIPLE CHOICE
1. For a tank circuit to maintain oscillation, ____ feedback is required.
a.
degenerative
c.
positive
b.
regenerative
d.
negative
2. ____ oscillators, a type of sinusoidal oscillators, use a tank circuit of capacitors and inductors,
connected either in series or parallel, to determine the frequency.
a.
LC
c.
RC
b.
Crystal
d.
Blocking
3. LC and ____ oscillators are used in the radio frequency (RF) range.
a.
relaxation
c.
RC
b.
blocking
d.
crystal
4. For low-frequency applications, ____ oscillators are used.
a.
LC
c.
blocking
b.
RC
d.
relaxation
5. The ____ oscillator is a variation of the Colpitts oscillator. The main difference is the addition of a
capacitor in series with the inductor in the tank circuit.
a.
Clapp
c.
Pierce
b.
Hartley
d.
Butler
6. The ____ oscillator is a two-transistor circuit. It uses a tank circuit, and the crystal determines the
frequency.
a.
Pierce
c.
phase-shift
b.
Butler
d.
Wien-bridge
7. A ____ oscillator is a conventional amplifier with a phase-shifting RC feedback network.
a.
Butler
c.
phase-shift
b.
Wien-bridge
d.
Hartley
8. A ____ oscillator is a two-stage amplifier with a lead-lag network and voltage divider.
a.
Pierce
c.
Butler
b.
phase-shift
d.
Wien-bridge
9. A ____ is a relaxation oscillator that can function in either of two temporarily stable conditions and is
capable of rapidly switching from one temporary state to the other.
a.
multivibrator
c.
Wien-bridge oscillator
b.
blocking oscillator
d.
phase-shift oscillator
10. A(n) ____ multivibrator is one type of free-running multivibrator. Its output is rectangular.
a.
blocking oscillator
c.
Butler oscillator
b.
astable
d.
Pierce oscillator
COMPLETION
1. A(n) ____________________ is a circuit that generates a repetitive AC signal.
2. ____________________ are materials that can convert mechanical energy to electrical energy when
pressure is applied or can convert electrical energy to mechanical energy when a voltage is applied.
3. A(n) ____________________ oscillator stores energy in a reactive component during one phase of the
oscillation cycle and gradually releases the energy during the relaxation phase of the cycle.
SHORT ANSWER
1. Describe how a tank circuit operates and maintains its oscillation.
2. Describe the basic sections of an oscillator.