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design oscillator 80-120 mhz range using bc547

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by.huseyin2046

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Can i design oscillator in this picture with using bc547, if yes, how i can do. .by the way in multism the oscillator in picture doesnt have output frequency in Mhz range.but cource lecturer did it!.
Adsız.jpg

(coil 0.18 microhenry)
 

I cropped your schematic so it is not as big as my neighbourhood.
C3 and R2 do nothing so I removed them.
 

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  • Hartley oscillator with Fets.png
    Hartley oscillator with Fets.png
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thanks a lot sir. how can i use bc547 transistor instead of fet. how can it be changed.
 
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A transistor needs base bias voltage and current for it to begin to turn on and amplify. A Jfet is already turned on and amplifies when it does not have any input bias voltage.
There are hundreds of schematics about your Hartley Oscillator in Google Images, some of them work.

Some of them show the transistor with no input bias so it will not work unless it is kick-started. Here is one showing the wrong symbol:
 

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FET threshold voltages are different than BJT ones and the first don't have almost gate current when BJTs work with a base current. The circuit will need modifications.
 

You can use any good CMOS logic inverter with good decoupling.
160MHz Osc.png
ω=(LC)e-½ where C is the series equivalent of C1, C2 and allow for stray and input capacitance of a few pF. Try here

Tuneable coil, varicap network or trimmer cap as your choice for tuning.
 

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