Return-Path: Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by klubnl.pl (8.14.4/8.14.4/Debian-8+deb8u2) with ESMTP id w1HLLXqw031266 for ; Sat, 17 Feb 2018 22:21:36 +0100 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1en9kC-0004BL-9d for rs_out_1@blacksheep.org; Sat, 17 Feb 2018 21:10:04 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1en9kB-0004BC-Fp for rsgb_lf_group@blacksheep.org; Sat, 17 Feb 2018 21:10:03 +0000 Received: from porthos.netcom.co.uk ([217.72.171.73]) by relay1.thorcom.net with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.89) (envelope-from ) id 1en9k8-0000Ko-K1 for rsgb_lf_group@blacksheep.org; Sat, 17 Feb 2018 21:10:02 +0000 X-DKIM-Result: Domain=abelian.org Result=Signature OK DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=abelian.org ; s=default; h=Content-Transfer-Encoding:Content-Type:In-Reply-To: MIME-Version:Date:Message-ID:From:References:To:Subject:Sender:Reply-To:Cc: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=2FuZiaUrk0A19Vq4P6f7oFuv1qvfikHRelqna71CxNY=; b=NFLLO+1+dHEo6d39sP02IJ37Sc MufHFTpUEl5SGNo1shyPHTrWLBb4jnlP3UvIxQNyJgrzKPsCDd/1hEzrVpb+bTGF0IGky82IEcoCF gY0oI70ru4d5IO3uyzgJDXHhmEscqKEH2BPUf/2jpK20ccvswO7JqusEXkRc1z9t0iYA=; Received: from i-194-106-52-83.freedom2surf.net ([194.106.52.83]:34499 helo=pn.abelian.org) by porthos.netcom.co.uk with esmtpsa (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.89_1) (envelope-from ) id 1en9k6-0000Sb-FW for rsgb_lf_group@blacksheep.org; Sat, 17 Feb 2018 21:09:58 +0000 Received: from [127.0.0.1] (localhost [127.0.0.1]) by pn.abelian.org (Postfix) with ESMTP id CCF8A400687 for ; Sat, 17 Feb 2018 21:09:57 +0000 (UTC) To: rsgb_lf_group@blacksheep.org References: <52dea779-7aae-aff8-1072-ad24cdcd007c@freenet.de> <4024a3ab-eb61-7801-e9ad-5715c5f49546@abelian.org> <9a7cf91a-5643-9149-28a7-ce6d282db3e9@abelian.org> <1555f07a-f2a3-fb55-c246-f52442a1a723@freenet.de> <4ac6d43f-85c7-bd05-85b9-5b64ebcfbf35@abelian.org> <2f6a408a-af27-9c9b-b116-7becd9b1c66f@abelian.org> <6eced61e-a7ce-2935-195d-4a76f375b11e@freenet.de> <633c1982-97fe-7d9d-7f69-07e3503147bb@abelian.org> <5A88244B.1020304@posteo.de> From: Paul Nicholson Message-ID: <1b3df450-bb19-b667-b784-17c8b48917db@abelian.org> Date: Sat, 17 Feb 2018 21:09:57 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.3.0 MIME-Version: 1.0 In-Reply-To: <5A88244B.1020304@posteo.de> Content-Language: en-US X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - porthos.netcom.co.uk X-AntiAbuse: Original Domain - blacksheep.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - abelian.org X-Get-Message-Sender-Via: porthos.netcom.co.uk: authenticated_id: catchall@abelian.org X-Authenticated-Sender: porthos.netcom.co.uk: catchall@abelian.org X-Spam-Score: 0.0 (/) X-Spam-Report: Spam detection software, running on the system "relay1.thorcom.net", has NOT identified this incoming email as spam. The original message has been attached to this so you can view it or label similar future email. If you have any questions, see the administrator of that system for details. Content preview: These glitches on the Octo input occur as the input signal passes through about +/- 1.4 volts. Regardless of the digital gain control setting. Still present if I bypass the input board and wire straight into the differential inputs on the Octo card. [...] Content analysis details: (0.0 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- 0.0 T_DKIM_INVALID DKIM-Signature header exists but is not valid X-Scan-Signature: 0a4643e586472c13187d293ec5d096c2 Subject: Re: LF: Testing Audioinjector Octo with RPi3 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.9 required=5.0 tests=FROM_ENDS_IN_NUMS autolearn=no version=2.63 X-SA-Exim-Scanned: Yes Sender: owner-rsgb_lf_group@blacksheep.org Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group X-SA-Exim-Rcpt-To: rs_out_1@blacksheep.org X-SA-Exim-Scanned: No; SAEximRunCond expanded to false These glitches on the Octo input occur as the input signal passes through about +/- 1.4 volts. Regardless of the digital gain control setting. Still present if I bypass the input board and wire straight into the differential inputs on the Octo card. Vanishes if I sample at 48k/sec instead of 96k/sec. I get about 30nS jitter on the PPS at 48k/sec. To eliminate vlfrx-tools I reproduced the fault using arecord into sox to convert to ASCII data and then plot with gnuplot, Occurs on two specimens of Octo and two Pi. If I keep the input signal below 1.4 volts, there are no noticeable artifacts but the PPS jitter is still no better than about 200nS at 96k/sec. The PPS is visibly noisy on the scope at 96k/sec but looks clean at 48k/sec. Tomorrow I'll look at the noise floor at various sample rates. -- Paul Nicholson --