Return-Path: Received: from mtain-da03.r1000.mx.aol.com (mtain-da03.r1000.mx.aol.com [172.29.64.75]) by air-mb05.mail.aol.com (v129.4) with ESMTP id MAILINMB051-a3834c24e9cf370; Fri, 25 Jun 2010 13:39:27 -0400 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by mtain-da03.r1000.mx.aol.com (Internet Inbound) with ESMTP id 4DDF138001862; Fri, 25 Jun 2010 13:39:20 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1OSCrH-00023O-9T for rs_out_1@blacksheep.org; Fri, 25 Jun 2010 18:38:31 +0100 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1OSCrG-00023F-S3 for rsgb_lf_group@blacksheep.org; Fri, 25 Jun 2010 18:38:30 +0100 Received: from cavuit02.kulnet.kuleuven.be ([134.58.240.44]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1OSCrF-0007uJ-61 for rsgb_lf_group@blacksheep.org; Fri, 25 Jun 2010 18:38:30 +0100 Received: from smtps02.kuleuven.be (smtpshost02.kulnet.kuleuven.be [134.58.240.75]) by cavuit02.kulnet.kuleuven.be (Postfix) with ESMTP id 580FE51C002 for ; Fri, 25 Jun 2010 19:38:21 +0200 (CEST) Received: from ICTS-S-HUB-N1.luna.kuleuven.be (icts-s-hub-n1.luna.kuleuven.be [10.112.9.11]) by smtps02.kuleuven.be (Postfix) with ESMTP id 4663AF3862 for ; Fri, 25 Jun 2010 19:38:21 +0200 (CEST) Received: from ICTS-S-EXC2-CA.luna.kuleuven.be ([10.112.11.13]) by ICTS-S-HUB-N1.luna.kuleuven.be ([10.112.9.11]) with mapi; Fri, 25 Jun 2010 19:38:21 +0200 X-Kuleuven: This mail passed the K.U.Leuven mailcluster From: Rik Strobbe To: "rsgb_lf_group@blacksheep.org" Date: Fri, 25 Jun 2010 19:33:49 +0200 Thread-Topic: 137kHz transmitters Thread-Index: AcsUjHFeEv/CrP9jS+6dQzNfF9Cs6AAACC/U Message-ID: References: In-Reply-To: Accept-Language: nl-NL, nl-BE Content-Language: nl-BE X-MS-Has-Attach: X-MS-TNEF-Correlator: acceptlanguage: nl-NL, nl-BE MIME-Version: 1.0 X-KULeuven-Information: Katholieke Universiteit Leuven X-KULeuven-Scanned: Found to be clean X-KULeuven-Envelope-From: rik.strobbe@fys.kuleuven.be X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001 Subject: LF: RE: 137kHz transmitters Content-Type: multipart/alternative; boundary="_000_BF4A524700075746A6467658DFC7102C51094D0DCFICTSSEXC2CAlu_" 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, TO_ADDRESS_EQ_REAL 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 x-aol-global-disposition: G x-aol-sid: 3039ac1d404b4c24e9c84eb8 X-AOL-IP: 193.82.116.20 X-Mailer: Unknown (No Version) --_000_BF4A524700075746A6467658DFC7102C51094D0DCFICTSSEXC2CAlu_ Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Roger, if you want to end up with a 50% duty cycle signal you need to divide by= 13 and then divide by 2. Divide by 13 can be done using a presetable 4 bit counter such as 74HC160= (http://www.datasheetcatalog.org/datasheet/philips/74hc160.pdf). 73, Rik ON7YD - OR7T ________________________________ Van: owner-rsgb_lf_group@blacksheep.org [owner-rsgb_lf_group@blacksheep.or= g] namens Roger Lapthorn [rogerlapthorn@gmail.com] Verzonden: vrijdag 25 juni 2010 19:29 Aan: rsgb_lf_group@blacksheep.org Onderwerp: LF: 137kHz transmitters 3560 and 3579kHz, both cheap crystals, divided by 26, give CW and QRSS fre= quencies on 136/137kHz. What is the simplest and cheapest way of getting= divide by 26? 73s Roger G3XBM -- http://g3xbm-qrp.blogspot.com/ http://www.g3xbm.co.uk http://www.youtube.com/user/g3xbm G3XBM GQRP 1678 ISWL G11088 --_000_BF4A524700075746A6467658DFC7102C51094D0DCFICTSSEXC2CAlu_ Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Roger,
 
if you want to end up with a 50% dut= y cycle signal you need to divide by 13 and then divide by 2.
Divide by 13 can be done using a pre= setable 4 bit counter such as 74HC160 (http://www.datasheetcatalog.org/dat= asheet/philips/74hc160.pdf).
 
73, Rik ON7YD - OR7T
 
Van: owner-rsgb_= lf_group@blacksheep.org [owner-rsgb_lf_group@blacksheep.org] namens Roger= Lapthorn [rogerlapthorn@gmail.com]
Verzonden: vrijdag 25 juni 2010 19:29
Aan: rsgb_lf_group@blacksheep.org
Onderwerp: LF: 137kHz transmitters

3560 and 3579kHz, both cheap crystals, divided by 26, give CW and QRS= S frequencies on 136/137kHz. What is the simplest and cheapest way of gett= ing divide by 26?

73s
Roger G3XBM

--
http://g3xbm-= qrp.blogspot.com/
http://www.g3xbm.co.u= k
http://www= .youtube.com/user/g3xbm
G3XBM    GQRP 1678      ISWL G11088
--_000_BF4A524700075746A6467658DFC7102C51094D0DCFICTSSEXC2CAlu_--