Return-Path: Received: (qmail 2825 invoked from network); 4 Dec 2002 19:44:03 -0000 Received: from netmail01.services.quay.plus.net (212.159.14.219) by mailstore with SMTP; 4 Dec 2002 19:44:03 -0000 Received: (qmail 18414 invoked by uid 10001); 4 Dec 2002 19:43:49 -0000 X-Priority: 3 X-MSMail-Priority: Normal Received: from post.thorcom.com (193.82.116.70) by netmail01.services.quay.plus.net with SMTP; 4 Dec 2002 19:43:49 -0000 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 X-SQ: A Received: from majordom by post.thorcom.com with local (Exim 4.10) id 18JfQf-0005Uf-00 for rsgb_lf_group-outgoing@blacksheep.org; Wed, 04 Dec 2002 19:43:29 +0000 Received: from [166.82.1.69] (helo=host4.ctc.net) by post.thorcom.com with esmtp (Exim 4.10) id 18JfQe-0005UV-00 for rsgb_lf_group@blacksheep.org; Wed, 04 Dec 2002 19:43:28 +0000 Received: from att.net ([166.82.181.250]) by host4.ctc.net (InterMail vK.4.03.05.03 201-232-132-103 license 2d687b22c655f23831a2faa19b737467) with ESMTP id <20021204194440.ETTU665.host4@att.net>; Wed, 4 Dec 2002 14:44:40 -0500 Message-ID: <3DEE5AE4.7614DC4@att.net> Date: Wed, 04 Dec 2002 19:43:32 +0000 From: "Dexter McIntyre W4DEX" X-Mailer: Mozilla 4.77 [en] (Win98; U) X-Accept-Language: en MIME-Version: 1.0 To: rsgb_lf_group@blacksheep.org, j.r.moritz@herts.ac.uk References: <5.1.0.14.0.20021202175331.027c0670@gemini.herts.ac.uk> Subject: Re: LF: W-G SPM-19 trouble (survives exploratory surgery) Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 8bit X-Spam-Status: No, hits=0.0 required=5.0tests=REFERENCES,SPAM_PHRASE_00_01,USER_AGENT_MOZILLA_XM, X_ACCEPT_LANGversion=2.42 Sender: Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group The SPM-19 lives! Thanks to Jim Moritz, I was able to locate the problem in the 40.01 MHz 2nd LO PLL circuit. A 2N918 transistor on the PLL board was open. Replaced it with a NTE161 and now the VCO is locked. A wandering VCO was causing the off frequency problem. Now to find holes for all those screws! What a beautifully engineered piece of equipment. W4DEX