Ok , their are 2 ways to create an ossilator using either negative/positive feedback or with an op-amp and the gain of 1 condition , phase condition forgot what it was called etc ....
Leaving off the op-amp way
Their are main ways to make ossilators based on negative/positive feedback..
i.e
Clapp oscillator
Colpitts oscillator
Costas loop
Hartley oscillator
to name a few ( all of then use the same method except use either more inductors then capacitors in parrell or series ...etc)
But what I want to know is
http://en.wikipedia.org/wiki/File:Cb_colp.svg
http://en.wikipedia.org/wiki/Clapp_oscillator
...etc
In these ossilator circuits basically the name of the game is to cancel out the resistance that dampers out the LC resonanting circuit...
I am wonder how adding just a transistor like in the case of
http://en.wikipedia.org/wiki/Clapp_oscillator
to a LC circuit makes it so the transistor supplies the exact negative or positive feedback to keep it's LC tank resonanting....?
Because as I look at these ossilator circuit they are just LC tank circuits with a transistor the only difference is some of them use more inductors or capacitor then others but this can all be reduced down to 1 L and 1C using series/parrellal circuit analysis. Still doesn't quite make since how the transistor feedsback the exact amount.... kind of like magic
Just wondering how the transistor gives the exact feedback need to keep it ossilating forever...
I guess I don't see how the transistor is going to close/open at the correct time to give the correct negative or postive feedback
Is the reason why the transistor is put their leg between 2 cap's for basing or something ....
If this is the case then at least one of the caps would have to be a specific fix value for basing but the other one could vary to be used to give different carrier frequencies or ossilations.
Also in this clapps ossilator must it be a specific type of transistor or could you use NPN or PNP ?
Thanks for any clarity
enough said I am repeating myself but by now you get the question
Leaving off the op-amp way
Their are main ways to make ossilators based on negative/positive feedback..
i.e
Clapp oscillator
Colpitts oscillator
Costas loop
Hartley oscillator
to name a few ( all of then use the same method except use either more inductors then capacitors in parrell or series ...etc)
But what I want to know is
http://en.wikipedia.org/wiki/File:Cb_colp.svg
http://en.wikipedia.org/wiki/Clapp_oscillator
...etc
In these ossilator circuits basically the name of the game is to cancel out the resistance that dampers out the LC resonanting circuit...
I am wonder how adding just a transistor like in the case of
http://en.wikipedia.org/wiki/Clapp_oscillator
to a LC circuit makes it so the transistor supplies the exact negative or positive feedback to keep it's LC tank resonanting....?
Because as I look at these ossilator circuit they are just LC tank circuits with a transistor the only difference is some of them use more inductors or capacitor then others but this can all be reduced down to 1 L and 1C using series/parrellal circuit analysis. Still doesn't quite make since how the transistor feedsback the exact amount.... kind of like magic
Just wondering how the transistor gives the exact feedback need to keep it ossilating forever...
I guess I don't see how the transistor is going to close/open at the correct time to give the correct negative or postive feedback
Is the reason why the transistor is put their leg between 2 cap's for basing or something ....
If this is the case then at least one of the caps would have to be a specific fix value for basing but the other one could vary to be used to give different carrier frequencies or ossilations.
Also in this clapps ossilator must it be a specific type of transistor or could you use NPN or PNP ?
Thanks for any clarity
enough said I am repeating myself but by now you get the question
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