thunderbird
New Member
Hello everyone,
I've successfully built the Simple FM Transmitter from Makezine , which is based on Testsuo Kogawa's design.
However, I have no clue how this works? An internet and Google searched resulted in LC oscillators (tanks). Both of them clearly have a capacitor in parallel with the inductor (at the transistor's collector). It does looks like a Colpitts' oscillator in some modified way. However, I can't really figure out how the FM carriers is generated, and how the amplitude I guess (?) of the input wave is modifying the carriers' frequency (to result in FM?).
Can someone give me an explanation? I (think) I understand the transistor DC principle (that it needs to have fit DC conditions (like 0.7V BE voltage) to amplify the voltage swing at the base. There I'm afraid it stops and I'm eager to know more!
Thanks for any help and insight!
An electronic lover eager to learn more about those "analog" circuits!
I've successfully built the Simple FM Transmitter from Makezine , which is based on Testsuo Kogawa's design.
However, I have no clue how this works? An internet and Google searched resulted in LC oscillators (tanks). Both of them clearly have a capacitor in parallel with the inductor (at the transistor's collector). It does looks like a Colpitts' oscillator in some modified way. However, I can't really figure out how the FM carriers is generated, and how the amplitude I guess (?) of the input wave is modifying the carriers' frequency (to result in FM?).
Can someone give me an explanation? I (think) I understand the transistor DC principle (that it needs to have fit DC conditions (like 0.7V BE voltage) to amplify the voltage swing at the base. There I'm afraid it stops and I'm eager to know more!
Thanks for any help and insight!
An electronic lover eager to learn more about those "analog" circuits!