- 1st January 2008, 21:03 #1

- Join Date
- Jun 2006
- Location
- bangalore india
- Posts
- 485
- Helped
- 43 / 43
- Points
- 4,655
- Level
- 16

## rc resonance

hai

i like to know working of rc resonence ocillator circuits

- 1st January 2008, 21:03

- 2nd January 2008, 01:42 #2

- Join Date
- Dec 2005
- Location
- Hrvatska (Croatia)
- Posts
- 14
- Helped
- 7 / 7
- Points
- 1,484
- Level
- 8

## resonance circuit

Same as Hartley and Colpitts oscillators... Basically idea is to create sufficient phase shift.

(The Barkhausen condition: if there is positive feedback with a phase 0 or 360 degrees, you will get oscillation).

- 2nd January 2008, 09:14 #3

- Join Date
- Oct 2005
- Location
- India
- Posts
- 1,804
- Helped
- 256 / 256
- Points
- 17,526
- Level
- 32

## rc circuit resonance

if there is positive feedback and the feedback given is equal to input then oscillation can be achieved... at a particular frequency the RC or any other resonant circuit used would satisfy this condition and at this frequency the circuit oscillates....

- 2nd January 2008, 23:38 #4

- Join Date
- Jul 2006
- Posts
- 121
- Helped
- 9 / 9
- Points
- 1,685
- Level
- 9

## resonant rc circuit

it works on Barkhausen Criteria

- 2nd January 2008, 23:38

- 4th January 2008, 13:37 #5

- Join Date
- Jun 2006
- Location
- bangalore india
- Posts
- 485
- Helped
- 43 / 43
- Points
- 4,655
- Level
- 16

## rc resonant

thanks for responds

i hear a fully charged capacitor if short to a inductor it will start damping resonance with out any other component

i like to get expla for this

- 4th January 2008, 14:47 #6

- Join Date
- Dec 2007
- Location
- Chennai-India
- Posts
- 169
- Helped
- 24 / 24
- Points
- 2,238
- Level
- 10

## resonance rc

hi,

there is one more condition for oscillation which the gain of the amplifier section (without considering feedback)has to be much much greater than 1 initially & finally gain should settle at a value greater than 1 to compensate the loss in the tank circuit.

With Regards

S.rajesh kumar

- 4th January 2008, 16:02 #7

- Join Date
- Oct 2005
- Location
- India
- Posts
- 1,804
- Helped
- 256 / 256
- Points
- 17,526
- Level
- 32

## r c resonance

the charged cap due to the charge passes current through the inductor and the inductor stores the energy as magnetic energy until the capacitor is able to supply current after that the inductor charges the cap and converts its stored energy to electrical energy... this repeats but due to some parasitic resistance some energy is dissipated leading to damped oscillations...

- 5th January 2008, 04:53 #8

- Join Date
- Nov 2004
- Location
- Tamilnadu
- Posts
- 657
- Helped
- 36 / 36
- Points
- 5,970
- Level
- 18

## rc resonance circuit

Originally Posted by**A.Anand Srinivasan**

- 5th January 2008, 11:09 #9

- Join Date
- Oct 2005
- Location
- India
- Posts
- 1,804
- Helped
- 256 / 256
- Points
- 17,526
- Level
- 32

## how does a circuit resonant without inductor

Originally Posted by**grittinjames**

i've replied to this post of grittinjames... better read the post well before stating out mistakes....

1 members found this post helpful.

- 5th January 2008, 15:59 #10

- Join Date
- Mar 2006
- Posts
- 29
- Helped
- 4 / 4
- Points
- 1,462
- Level
- 8

## rc resonant circuit

hi

the answer is simple

this type of oscillator works on the phase shifht

one of the 2 conditions of the oscillation is to make the phase shift betwwn the output of the feedback circuit and the input of the amplifier zero

this is why we put many cells of rc circuits