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From: Bill Sloman <bill.sloman@ieee.org>
Newsgroups: sci.electronics.design
Subject: Re: Random thoughts on sinewave oscillators
Date: Fri, 18 Oct 2024 16:29:14 +1100
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On 17/10/2024 7:55 am, Edward Rawde wrote:
> Is the reason why this doesn't produce a better looking sinewave because the amplifier slew rate is faster going down than it is
> going up or some other reason?
> 
> Ignore the wild decoupling, it took me long enough to get the concept to work at all.
> 
> I'm aware that a single package containing two op amps could probably do a much better job.

https://www.analog.com/media/en/technical-documentation/application-notes/AN132f.pdf

has a pretty good example of a sine wave oscillator. I've speculated 
that a four quadrant analogue multiplier could offer a better gain 
control mechanism.

https://www.analog.com/media/en/technical-documentation/data-sheets/AD734.pdf

though it is hideously expensive. The simulation I worked up used two 
with the second one controlling a quadrature input to give you smooth 
control of the frequency of oscillation in addition to its amplitude.

I thought about building one, but there's no obvious application.

-- 
Bill Sloman, Sydney