## Re: [Qucs-help] Frequency Measure in a Colpitts oscillator

 Re: [Qucs-help] Frequency Measure in a Colpitts oscillator From: Stefan Jahn - 2007-09-11 19:27:24 ```Am Di, 11.09.2007, 10:01, schrieb Emmanuel Fernandes: > Hello everybody! Hi Emmanuel, > I am simulating a special configuration of a Colpitts oscillator based on > a > NPN BJT. I just wanted to know how I can use QUCS to measure the frequency > of the output signal. Hm. Probably I think too complicated... but this is my suggestion: 1. simulate oscillator in time domain using transient simulation 2. setup equations for freq. measurement: vout=out.Vt Vout=Time2Freq(vout,time) Vpk=max(Vout) freq=xvalue(Vout,Vpk) "freq" should then contain the frequency value for the maximum peak in the spectrum of the ouput time domain signal... Hope this helps, Stefan. ```

 [Qucs-help] Frequency Measure in a Colpitts oscillator From: Emmanuel Fernandes - 2007-09-11 08:22:42 ```Hello everybody! I am simulating a special configuration of a Colpitts oscillator based on a NPN BJT. I just wanted to know how I can use QUCS to measure the frequency of the output signal. Thanks for any reply, Emmanuel. ```
 Re: [Qucs-help] Frequency Measure in a Colpitts oscillator From: Stefan Jahn - 2007-09-11 19:27:24 ```Am Di, 11.09.2007, 10:01, schrieb Emmanuel Fernandes: > Hello everybody! Hi Emmanuel, > I am simulating a special configuration of a Colpitts oscillator based on > a > NPN BJT. I just wanted to know how I can use QUCS to measure the frequency > of the output signal. Hm. Probably I think too complicated... but this is my suggestion: 1. simulate oscillator in time domain using transient simulation 2. setup equations for freq. measurement: vout=out.Vt Vout=Time2Freq(vout,time) Vpk=max(Vout) freq=xvalue(Vout,Vpk) "freq" should then contain the frequency value for the maximum peak in the spectrum of the ouput time domain signal... Hope this helps, Stefan. ```