Yesterday I learned of and looked up Colpitts Oscillator and so threw it together from here
http://www.electronics-tutorials.ws/oscillator/colpitts.htmlI made this 1 with pretty much the same Rs and Cs
And my DMM said it was oscillating at about 1.8kHz or maybe 2.4kHz. So I wanted to hear it and spent 1-2 hours trying to get a little mini speaker hooked up to it, and I tried a 1 BJT driver, and none of it worked, and then I didn't know if I had a peizo buzzer or a speaker or what was wrong or if I just was doing it all wrong for setting up the trannie
So I was like this
LOL, gotta love those cats
So I built a little 555 circuit to make sure I could work the speaker, and it worked fine. So I checked the Colpitts Osc with my DSO and it wasn't showing any noticeable oscillation, just a fixed 2V output from the 741 opamp, and hence why the speaker did nothing.
I never bothered with any equations to even see what freq. it was supposed to work at, or the amplitude, but it was fixed on my scope.
So what am I missing here ? I'll play with it again now soon, but my DMM does work fine for Hz in my limited experience, and the scope confirms it usually.