I am trying to design a common collector colpitts oscillator, it looks more like a unity gain voltage amplifier with step up voltage transformer in the feedback!.
The following stuff is known:
β=300
corner frequency(fc)=8k Hz
Ic=0.1mA
Vcc=10V
L=30nH
Cr1=50pF
Cr2=30pF
 I need to find the values of Rc, Re, Rbb to bias the oscillator to Ic=0.1mA, the part confusing me here is that I can't neglect the transistor input impedance looking into the base. Cb can be assumed to be very large.
 How can I calculate the white noise level of the amplifier?
 Calculating the center freq and Q of the oscillator, I think that freq can come from \(\omega\)=\(\frac{(Cr1+Cr2)}{Cr1*Cr2*L}\) is this correct??
 How do I calculate the Lesson corner freq. ?
 Whats the difference between the noise spectrum of the oscillator and that of the amplifier?
The following stuff is known:
β=300
corner frequency(fc)=8k Hz
Ic=0.1mA
Vcc=10V
L=30nH
Cr1=50pF
Cr2=30pF
 I need to find the values of Rc, Re, Rbb to bias the oscillator to Ic=0.1mA, the part confusing me here is that I can't neglect the transistor input impedance looking into the base. Cb can be assumed to be very large.
 How can I calculate the white noise level of the amplifier?
 Calculating the center freq and Q of the oscillator, I think that freq can come from \(\omega\)=\(\frac{(Cr1+Cr2)}{Cr1*Cr2*L}\) is this correct??
 How do I calculate the Lesson corner freq. ?
 Whats the difference between the noise spectrum of the oscillator and that of the amplifier?
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