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 x6KFeq4i025865 for ; Sat, 20 Jul 2019 17:40:54 +0200 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1horFk-0008Dg-SA for rs_out_1@blacksheep.org; Sat, 20 Jul 2019 16:26:28 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1horEU-0008Cq-1M for rsgb_lf_group@blacksheep.org; Sat, 20 Jul 2019 16:25:10 +0100 Received: from mail-vs1-xe33.google.com ([2607:f8b0:4864:20::e33]) by relay1.thorcom.net with esmtps (TLSv1.3:TLS_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1horER-0007DC-QA for rsgb_lf_group@blacksheep.org; Sat, 20 Jul 2019 16:25:08 +0100 Received: by mail-vs1-xe33.google.com with SMTP id 2so23410718vso.8 for ; Sat, 20 Jul 2019 08:25:04 -0700 (PDT) X-DKIM-Result: Domain=gmail.com Result=Good and Known Domain DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:from:date:message-id:subject:to; bh=d6iPSyU8OEIJnnH1ZU4XEsXb6XBkKUHZGlS0BAmnpMM=; b=qf1zqvS1Wh9dwsG8IFWR10nkuW5wHxzy9Rr8CuRgZJogtKcFvwNl/DV5j7HOACdoAO Qf76MNoNRbOmFSkuMWHQ4GDuFOBqoUAZpV1laWRq+CtA+GyAi8uZ9yUTUvjAHeEnIP1e UAr5UsViHuhYDsT9eLYm+ok/feZ60ci38vR5/xPZZzXO3Lto9CbiafyNaTzD4uXQ2Pqw ER/gZ5jFnM9l1vvFvydGKlbPCTcAMHubNF5M+Oyru3aV9ocdOs+E4XcQbniGGBaIhbso 5NMNZ/197STSX5L3IjMfhmptAAnQgydBFWFfiXalrIIyuhaDba72S8JRtZONiLkEdVRk JPog== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:from:date:message-id:subject:to; bh=d6iPSyU8OEIJnnH1ZU4XEsXb6XBkKUHZGlS0BAmnpMM=; b=jsrcLtF9XtAm0kuhysIm6e6i1R3EU7eOU6PeciqWq6HDaM+SJrS7RZoNuirj1x/1Bc AXEXMoVn9lFI3zL8/DvUhu+g6zCi3/cHKqTFmnjG7LnmOtRY0+dveu0VWq/pkzbRJt4d h4NGa0W/TvT1T6btlCIfpm9Q86LJo+Siqw5u45Byq9zUCHWVyKU6IeHKMjAjfz6wSNuX dgUn0gHg7AHvYe4uko4gg1Wb0y4JB2eQ1FN4avRMe0aY4//XhgwCjEwcjpMFOBkp+yXb K4+7yvKTXwewZLFgmJJntRIh19Zdqg0Fg9gTv7IEHZPG+EzCl0N3CZP4Is9bUDcijMwn qZzw== X-Gm-Message-State: APjAAAXSdi8gsAPMZzpMD2li+nbJBfvb5KTSpF58dKBviVdg3FSk/BjU eXp3FoJIu0JAElikvVR/x8A47D6CWxY6yLhgcj8= X-Google-Smtp-Source: APXvYqyPPy06N/C4KnoNnAcD+p9nu/6ImfePgEXbJQX3A4gv3ADTs9KiL5m9M5VGpiriLVInZwkfXE8JuYhjDBMQiL4= X-Received: by 2002:a67:2bc4:: with SMTP id r187mr35226864vsr.102.1563636303026; Sat, 20 Jul 2019 08:25:03 -0700 (PDT) MIME-Version: 1.0 From: Andy Talbot Date: Sat, 20 Jul 2019 16:24:52 +0100 Message-ID: To: "UK Microwaves groups.io" , rsgb-lf-group@groups.io, "rsgb_lf_group@blacksheep.org" X-Spam-Score: -0.2 (/) X-Spam-Report: Spam detection software, running on the system "relay1.thorcom.net", has NOT identified this incoming email as spam. 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Content preview: Does anyone know how, or if, the k and q values listed for filters in books like Zverev or Mathei Young and Jones can be converted to cutoff frequency and damping for each of the stages of a Sallen-Ke [...] Content analysis details: (-0.2 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at http://www.dnswl.org/, no trust [2607:f8b0:4864:20:0:0:0:e33 listed in] [list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (andy.g4jnt[at]gmail.com) 0.0 HTML_MESSAGE BODY: HTML included in message -0.1 DKIM_VALID_EF Message has a valid DKIM or DK signature from envelope-from domain -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's domain X-Scan-Signature: 49f0f587e44d6711c57b8a4e950ba850 Subject: LF: Active Filters and k, q values Content-Type: multipart/alternative; boundary="000000000000665dc0058e1e72fb" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.5 required=5.0 tests=HTML_40_50,HTML_MESSAGE 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 --000000000000665dc0058e1e72fb Content-Type: text/plain; charset="UTF-8" Does anyone know how, or if, the k and q values listed for filters in books like Zverev or Mathei Young and Jones can be converted to cutoff frequency and damping for each of the stages of a Sallen-Key opamp filter ? I have the "Active-Filter Cookbook" by Don Lancaster, which has plenty of designs and examples but only for a very small number of basic filter shapes and only up to order six. Whereas those books have pages upon pages of values for every size and shape imaginable and more besides. It's just turning the values into the form needed for opamps I don't know how. The Cookbook does delve into the maths behind active filter design, but I'm still missing some fundamental connection. Andy www.g4jnt.com --000000000000665dc0058e1e72fb Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Does anyone know how, or if, the k and q values = listed for filters in books like Zverev or=C2=A0 Mathei Young and Jones can= be converted to cutoff frequency and damping for each of the stages of a S= allen-Key opamp filter ?

I have the &quo= t;Active-Filter Cookbook" by Don Lancaster, which has plenty of design= s and examples but only for a very small number of basic filter shapes and = only up to order six.=C2=A0 Whereas those books have pages upon pages of va= lues for every size and shape imaginable and more besides.
=
It's just turning the values into the form needed f= or opamps I don't know how.
The Cookbook does delve into= the maths behind active filter design, but I'm still missing some fund= amental connection.

<= div dir=3D"ltr">
Andy
www.g4jnt.com

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