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From: "Edward Rawde" <invalid@invalid.invalid>
Newsgroups: sci.electronics.design
Subject: Re: Low distortion sinewave oscillator without big capacitor.
Date: Tue, 8 Apr 2025 21:04:25 -0400
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"JM" <sunaecoNoChoppedPork@gmail.com> wrote in message news:vhabvj1uo56ikdhu8if219rvtfal6lijee@4ax.com...
> On Tue, 8 Apr 2025 14:41:44 -0400, "Edward Rawde"
> <invalid@invalid.invalid> wrote:
>
>>"JM" <sunaecoNoChoppedPork@gmail.com> wrote in message news:8099vjhs62eofoioejtlssoa19ifjrdvcg@4ax.com...
>>> On Mon, 7 Apr 2025 22:46:13 -0400, "Edward Rawde"
>>> <invalid@invalid.invalid> wrote:
>>>
>>>>"Edward Rawde" <invalid@invalid.invalid> wrote in message news:vsso97$1imi$1@nnrp.usenet.blueworldhosting.com...
>>>>> "JM" <sunaecoNoChoppedPork@gmail.com> wrote in message news:tcl2vjp49q4ga21itrpnmr4u3ts06vqffd@4ax.com...
>>>>>> On Fri, 4 Apr 2025 23:55:11 -0400, "Edward Rawde"
>>>>>> <invalid@invalid.invalid> wrote:
>>>>>>
>>>>>>>"JM" <sunaecoNoChoppedPork@gmail.com> wrote in message news:uop0vjp3d13t441ujfboi5aeeg08anm1je@4ax.com...
>>>>>>>> On Fri, 4 Apr 2025 16:29:27 -0400, "Edward Rawde"
>>>>>>>> <invalid@invalid.invalid> wrote:
>>>>>>>>
>>>>>>>>>"JM" <sunaecoNoChoppedPork@gmail.com> wrote in message news:add0vjdh2gcma0n9pfunq76n04cfbkhtnj@4ax.com...
>>>>>>>>>> On Fri, 4 Apr 2025 14:25:29 -0400, "Edward Rawde"
>>>>>>>>>> <invalid@invalid.invalid> wrote:
>>>>>>>>>>
>>>>>>>>>>>"Bill Sloman" <bill.sloman@ieee.org> wrote in message news:vsnufh$2ou7j$1@dont-email.me...
>>>>>>>>>>>> On 4/04/2025 11:33 am, JM wrote:
>>>>>>>>>>>>> On Thu, 3 Apr 2025 19:25:33 -0400, "Edward Rawde"
>>>>>>>>>>>>> <invalid@invalid.invalid> wrote:
>>>>>>>>>>>>>
>>>>>>>>>>>>>> "JM" <sunaecoNoChoppedPork@gmail.com> wrote in message news:qq8tujlpciqc2jrd0ibljmjr9pd37ip6hi@4ax.com...
>>>>>>>>>>>>>>> On Sun, 30 Mar 2025 14:54:56 -0400, "Edward Rawde"
>>>>>>>>>>>>>>> <invalid@invalid.invalid> wrote:
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> Not long ago JM posted a 1KHz sinewave oscillator with very low distortion.
>>>>>>>>>>>>>>>> It used a 470uF non polarized capacitor which in practice would probably be made from two 1000uF capacitors.
>>>>>>>>>>>>>>>> There's nothing wrong with that but I wanted to see whether I could make a working circuit without needing such a
>>>>>>>>>>>>>>>> large
>>>>>>>>>>>>>>>> capacitor.
>>>>>>>>>>>>....
>>>>
>>>>Here's an almost fully practical circuit except for the current sources and sinks.
>>>>
>>>
>>> I reversed the polarity of the control feedback and applied it to the
>>> inverting input of the first oscilllator stage,  removed some
>>> redundant capacitors, and added some filtering to the gain control
>>> signal.  Also altered some gain values to improve the dynamics (but
>>> that still has to be addressed).
>>>
>>> Most real world designs would use a sample and hold circuit to sample
>>> the output at it's maximum point and use that to control the feedback,
>>> similar to the topology I think I posted a while ago.  It might be
>>> worthwhile looking at that.
>>>
>>>
>>Thanks. That has the lowest distortion I've seen in a simulation so far.
>>
>>I can't find the sample/hold circuit you mentioned, would you mind reposting it?
>>
>>Thank you for your help with this. It is much appreciated.
>>
>>
>

Is the sample/hold circuit the one below?

After much digging I found it in a very interesting thread started by Bill Sloman on 5th February 2025 "The low distortion 
oscillator problem".

I can't get it to simulate in 24.1.5
something to do with unknown parameter in table{-2m,0,2m,1}

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