Return-Path: X-Spam-DCC: paranoid 104; Body=2 Fuz1=2 Fuz2=2 X-Spam-Checker-Version: SpamAssassin 3.1.3 (2006-06-01) on lipkowski.org X-Spam-Level: X-Spam-Status: No, score=-0.5 required=5.0 tests=BAYES_00,DNS_FROM_AHBL_RHSBL, FORGED_RCVD_HELO,RATWARE_GECKO_BUILD,SPF_PASS autolearn=no version=3.1.3 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by paranoid.lipkowski.org (8.13.7/8.13.7) with ESMTP id u22CLZqT014700 for ; Wed, 2 Mar 2016 13:21:35 +0100 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1ab5iB-0007fO-Dd for rs_out_1@blacksheep.org; Wed, 02 Mar 2016 12:17:03 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1ab5iB-0007fF-5g for rsgb_lf_group@blacksheep.org; Wed, 02 Mar 2016 12:17:03 +0000 Received: from brian.netcom.co.uk ([217.72.171.64]) by relay1.thorcom.net with esmtp (Exim 4.86) (envelope-from ) id 1ab5i9-0004C6-Lv for rsgb_lf_group@blacksheep.org; Wed, 02 Mar 2016 12:17:02 +0000 Received: from sb.abelian.org (i-194-106-52-83.freedom2surf.net [194.106.52.83]) by brian.netcom.co.uk (Postfix) with ESMTP id 3C0A53200D5 for ; Wed, 2 Mar 2016 11:54:25 +0000 (GMT) Received: from [127.0.0.1] (localhost [127.0.0.1]) by sb.abelian.org (Postfix) with ESMTP id C834B28A0135 for ; Wed, 2 Mar 2016 12:17:00 +0000 (UTC) Message-ID: <56D6D9BC.2040308@abelian.org> Date: Wed, 02 Mar 2016 12:17:00 +0000 From: Paul Nicholson User-Agent: Mozilla/5.0 (X11; Linux i686; rv:17.0) Gecko/20130106 Thunderbird/17.0.2 MIME-Version: 1.0 To: rsgb_lf_group@blacksheep.org X-Scan-Signature: 1f795a2ee1ecd56682b47ad11969b3d3 Subject: LF: A divider with no power supply Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit 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 X-Scanned-By: MIMEDefang 2.56 on 10.1.3.11 Status: O X-Status: X-Keywords: X-UID: 7168 I just discovered something as I turned off the 12V supply to the CD4040 I've been using to divide 477.69kHz by 16. With the supply off - it still works - with a nice square 29855.625 Hz output! It seems that the input to the divider, 477.69kHz sine at 4.5V peak biased at about 6V is passing through the input protection diodes of the CD4040 and supplying the Vdd rail quite sufficiently for the divider to operator. The rail voltage is 7.76V and the output is a square with amplitude 7.4V. -- Paul Nicholson --