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From: "Edward Rawde" <invalid@invalid.invalid>
Newsgroups: sci.electronics.design
Subject: Re: The low distortion oscillator problem
Date: Thu, 6 Feb 2025 12:06:39 -0500
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"JM" <sunaecoNoChoppedPork@gmail.com> wrote in message news:isg8qj15nkgl5cg41lgt4h4oav3bbgej2n@4ax.com...
> On Thu, 6 Feb 2025 03:58:59 +1100, Bill Sloman <bill.sloman@ieee.org>
> wrote:
>
>>There have been quite a few postings about 1kHz low distortion sine wave
>>oscillators.
>>
>>The problem is that if you want a get stable output from a sine wave
>>oscillator you have to add a non-linear element to control the gain
>>around the oscillating circuit.
>>
>
> You don't.
>

There are plenty of examples out there claiming to be a stable output sinewave oscillator, with no obvious non-linear element.

https://www.google.ca/search?q=sinewave+oscillator&udm=2

But a quick simulation of one of them (a 2kHz oscillator) shows that it's not even 40dB down at 4kHz.

Maybe folow that with a Chebychev low pass filter with a zero in the stop band at 4kHz.

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