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Sender: "piclist-bounces@mit.edu" Date: Tue, 6 Oct 2020 12:40:22 -0700 Subject: Re: [EE] Looking for technique to record audio after level exceeds some value Thread-Topic: [EE] Looking for technique to record audio after level exceeds some value Thread-Index: AdacGclNrv6ucciCTXSIsE/5Sa6pzg== Message-ID: References: List-Help: List-Subscribe: , List-Unsubscribe: , In-Reply-To: Reply-To: Microcontroller discussion list - Public. Accept-Language: en-US X-MS-Exchange-Organization-AuthAs: Anonymous X-MS-Exchange-Organization-AuthSource: TS500.efplus4.local X-MS-Has-Attach: X-Auto-Response-Suppress: All X-MS-Exchange-Organization-SenderIdResult: TempError X-MS-Exchange-Organization-PRD: mit.edu X-MS-TNEF-Correlator: received-spf: Pass (protection.outlook.com: domain of badtech.org designates 209.85.167.51 as permitted sender) receiver=protection.outlook.com; client-ip=209.85.167.51; helo=mail-lf1-f51.google.com; dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=badtech-org.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to; bh=/BBXheruOkYGkNWU2Jf4Rc7FCAK/09ZGQSD68W5YwIk=; b=qESnrNliO9KfSKCZX2vhgp3w1kqDRj5mUYo56dPC7UnMM86rrUI68lLpJxubSsY9MR kJ230PTnnWd0Hz8TKZUmfBS93+ybdAv2An7p2fEKKpBhtuw0Gp+rUo7HXc9wlsE0Ke+s QprozyYesCPjlngZrCph/vukjKB8HlbgemGuoMAHbq8jqO3ZBOzfiHMPN4uklrJbGX2d ibWU5SKnIpsJZBgVRFmN8IP7F+Q+BjhQ2ZRPWRpyj8S5AwC6vIxIi16u1KH1y0g6z9LA NjnHIso6uB3QwBEPxbWbiL9J77F1Ia/AQc+3q/FcTwenXQSZqb5VeE4DR/pUZVikdRYE qMfQ== authentication-results: spf=pass (sender IP is 209.85.167.51) smtp.mailfrom=badtech.org; mit.edu; dkim=pass (signature was verified) header.d=badtech-org.20150623.gappssmtp.com; mit.edu; dmarc=bestguesspass action=none header.from=badtech.org; errors-to: piclist-bounces@mit.edu list-id: "Microcontroller discussion list - Public." list-post: x-beenthere: piclist@mit.edu x-mailman-version: 2.1.6 x-received: by 2002:ac2:46d1:: with SMTP id p17mr1109992lfo.216.1602013234488; Tue, 06 Oct 2020 12:40:34 -0700 (PDT) x-topics: [EE] x-content-filtered-by: Mailman/MimeDel 2.1.6 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 On Tue, Oct 6, 2020 at 3:19 PM Dwayne Reid wrote: > > What I would like to do is to set up one of my spare Android devices > with the microphone in the heating duct. But I need some way to have > the device record just of few seconds BEFORE the explosion occurs as > well as a few seconds AFTER the explosion occurs. > > > I would record for as long as it takes to capture the event, then load th= e audio in an editor like Audacity, one with a time spectrogram and go look for the event visually. https://www.audacityteam.org/about/screenshots/ However, this is dependent on not capturing ambient noises. --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .