Oscillators Objectives Part 02
21 . Schmitt trigger Circuit Can be used for converting a sine wave to square wave.
22 . tuned circuit is used for frequency stabilization of an oscillator.
23 . relaxation oscillator incorporates two interdependent circuits in such way that output of each control the input of other.
24 . By increasing in transistor gain Oscillator can stop Oscillating.
25 . In Oscillation shown the feedback is regenerative
26 . which component varies the oscillator frequency C1
27 . typical frequency for a RC feedback Oscillator is 1KHz.
28 . When a 6 MHz crystal is followed by a frequency tripler, the output will be 18 MHz.
29 . A typical resonant frequency for a crystal oscillator. is 3.275 MHz
30. Typical Q for a crystal is 25000.
31 . An oscillator using a capacitive voltage di vider to provide feedback is Colpitts.
32 . RF feedback oscillators are usually tuned by varying the L or C.
33 . Oscillator shown is Voltage controlled Oscillator.
34 . higher positive Dc control Voltage will make the Oscillator frequency higher.
35 . Crystall controlled Oscillator is best frequency stability and accuracy.
36 . Colpit Oscillator fig 20.
38 . L1 component is varied to tune OSCILLATORS.
39 . In a free running multivibrator, each stage is cut-off for 1 us. the oscillator frequency is 0.5 MHz.
40 . TO generate a I kHz note, the most suitable circuit is Wein bridge oscillator.