Path: ...!eternal-september.org!feeder2.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail From: Bill Sloman Newsgroups: sci.electronics.design Subject: Re: High purity 1kHz oscillator Date: Fri, 25 Oct 2024 15:25:07 +1100 Organization: A noiseless patient Spider Lines: 41 Message-ID: References: <73pkhjpq08ui9ttooco6i07agdpcd0bp37@4ax.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Injection-Date: Fri, 25 Oct 2024 06:25:19 +0200 (CEST) Injection-Info: dont-email.me; posting-host="89a57dbd1e18c41d55b09ec784083237"; logging-data="3178239"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1/y5q3so1zVSW5bIwVyVkR00ujdDiBTorE=" User-Agent: Mozilla Thunderbird Cancel-Lock: sha1:siHG+e6qFxB+FQex9nWt/gV35vM= In-Reply-To: X-Antivirus-Status: Clean X-Antivirus: Norton (VPS 241025-0, 25/10/2024), Outbound message Content-Language: en-US Bytes: 2783 On 25/10/2024 4:48 am, JM wrote: > On Thu, 24 Oct 2024 16:16:49 +0100, JM wrote: > >> On Wed, 23 Oct 2024 02:05:52 +0100, JM wrote: >> >>> On Tue, 22 Oct 2024 01:10:41 -0400, "Edward Rawde" wrote: >>> >>>> But I suspect that component tolerances and mismatched FETs will ruin it. >>>> >>>> Otherwise it should be easy to get 60dB down on unwanted harmonics with a better filter. >>>> >>>> FWIW I likely won't be here for the next week. >>>> >>> >>> If you actually need a low distortion oscillator look for Viktor Mickevic's designs on diyaudio. I've attached a schematic. >>> >>> PK >>  >> >> It seems that I have a problem posting encoded binariesto this group with my provider. Attached is a link instead. >> >> https://1drv.ms/u/c/1af24d72a509cd48/EakMPPRi-pdLgaAKtJ2rrwwBNMGZZsy84MV2QoH1dPcZJQ?e=o59V9a > > And that links to an incorrect schematic - the rectified output tap is connected to the wrong node. Might be other errors.. Even so, the third harmonic is 78dB below the fundamental. The simulation runs slowly on my computer, so it may take me a while to get the schematic to where the designer intended it to be. The choice of op amp is what I'd expect from an audio group - it does seem to be a low distortion part. I just seem to have wrecked the .raw file from the simulation, so it may be a while before I have more to say. -- Bill Sloman, Sydney -- Bill Sloman, Sydney