用于振荡电路的振荡元件有LC、CR、陶瓷谐振器、石英晶体振动器。虽然各有长短，但从价格、形状、频率稳定性等方面来看，陶瓷谐振器在总体上最优越。
最近，VOC(Voltage Controlled Oscillator)以最初的自由调整(free adjustment)和优越的稳定性(good stability)等为由，广为利用。
VOC具备宽大的可变频率范围和优越的稳定性，谐振器具有比石英晶体结晶(quart crystal)低的机械Q(Qm)，所以适合获得宽大的可变频率范围，如表2)所示，初期频率范围(initial frequency tolerence)和长期稳定性也比CR、LC振荡电路优越。
NAME
PRICE
SIZE
ADJUSTMENT
OSCILLATION FREQUENCY
INITIAL TOLERANCE
LONG-TERM STABILITY
LC
Inexpensive
Big
Required
±2.0%
Fair
RC
Inexpensive
Small
Required
±2.0%
Fair
CRYSTAL
RESONATOR
Expensive
Big
Not Required
±0.001%
Excellent
CERAMIC
RESONATOR
Inexpensive
Small
Not Required
±0.2~±0.5%
Excellent
