Help with Oscillator

[SuperGeo]

Hello

I need some help with an oscillator I have here


the resistor in series with +9v is 4k7

check the picture, I belive it's an Twin-T oscillator right? well, values I used are in the picture, used an BC549 transistor.

everything right, I conected the output (dot) in my PC amplifier (those two little boxes every pc has, I just forgot the name) but it had no sound!

I think it's right, the circuit is very small but I can't make it to work :/ Tried to put an Capacitor in the output but It changed nothing. Can It be the transistor?

Another thing... the hole Idea was to make 2 oscillators:

One send timing pulses of DC (controlled by me) to power the Twin-T oscillator and make it oscillates

so it would keep bip bip bip (or another sound adjusting the frequency of the Twin-T) controlled by the first oscillator that keeps pulsing in a time set by me.

Anyone has any Idea of an oscillator that send pulses that the time can be controlled?

thats it
thanks

[Paul Perry (Frostwave)]

There is no bias on the base of the transistor.
I don't know if that matters, but try putting a pair of 470K resistors on the base, one to + and one to ground.

As for sending controlled pulses, that is a job for a 555 timer!!

http://www.4qdtec.com/singen.html has some interestign things, including a twin-T that appears to have a 470K from base to +, maybe try that resistor first.

[SuperGeo]

It's because that circuit was in some electronic magazines I have here :S


I'll test the bias thing, and post results soon

[Paul Perry (Frostwave)]

I just had another (better) look at the circuit, and there IS dc bias for the transistor, via the two Rs in series.
Maybe the resistor to the 9v supply is too large?