Return-Path: Received: from rly-dd02.mx.aol.com (rly-dd02.mail.aol.com [172.19.141.149]) by air-dd07.mail.aol.com (v125.7) with ESMTP id MAILINDD072-b624afbf28c70; Thu, 12 Nov 2009 06:33:56 -0500 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by rly-dd02.mx.aol.com (v125.7) with ESMTP id MAILRELAYINDD024-b624afbf28c70; Thu, 12 Nov 2009 06:33:34 -0500 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1N8XuT-0006W7-B1 for rs_out_1@blacksheep.org; Thu, 12 Nov 2009 11:32:17 +0000 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1N8XuS-0006Vy-Ox for rsgb_lf_group@blacksheep.org; Thu, 12 Nov 2009 11:32:16 +0000 Received: from smtp819.mail.ird.yahoo.com ([77.238.189.19]) by relay1.thorcom.net with smtp (Exim 4.63) (envelope-from ) id 1N8Xtl-0005RX-0U for rsgb_lf_group@blacksheep.org; Thu, 12 Nov 2009 11:31:37 +0000 Received: (qmail 8719 invoked from network); 12 Nov 2009 11:32:05 -0000 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=btinternet.com; h=Received:X-Yahoo-SMTP:X-YMail-OSG:X-Yahoo-Newman-Property:Message-ID:From:To:References:Subject:Date:MIME-Version:Content-Type:Content-Transfer-Encoding:X-Priority:X-MSMail-Priority:X-Mailer:X-MimeOLE; b=GnfJWyAGqw0OytSl+RQY/LScXnCDRjyi+OYBSvMmJV3e3yNEvz+8KvYie+Za42RrmSK9hltOd0XWYLVTT5CqPD7VSQo8ghR0uiyTeF0rBYliuq17MDUbaR75MHhX9UfX6tBLsDVg6+jVnrZUPx7T83oD/TQpAKA5O7+c+uVt46g= ; Received: from unknown (HELO lark) (alan.melia@213.122.9.244 with login) by smtp819.mail.ird.yahoo.com with SMTP; 12 Nov 2009 11:32:03 -0000 X-Yahoo-SMTP: KHdpK2OswBBXlm4uxknbEiS4uYdJoGknHN90u4K8__lTafnafZg- X-YMail-OSG: TEvFAjoVM1lc2WfFrARw5N2pXeJDEzgt3ikHzsLCGhLrbvK4PW3g5i_KKeIKHLQNm1hvbB1nUEPJF7zVe2gNXsi80hmIMlVRT8ecr1HNlPDvqphOFcaGOFBBpjOyMAz.MjFuN3l8_NoRWv.Q.CxpgbXStepIyR4tsqPpmQcRtI_Kt3MWiVYFx2GuYNa2CS41Zx4FMWJg4E.a8KUbQ5cgoquTRI6hIiO.QqH8KPimrsoQTAN4TueCyv5GIOHIwJ4ZsgZBFkp_Tk7XS9OC1Hd3z2lMpcUtFZWaeCHtUs.jEuQV236Q063lR9Qf6KaraBRS5qZDCnvhhuMvhtBga0e6bQBd X-Yahoo-Newman-Property: ymail-3 Message-ID: <005001ca638b$c6dce610$0900a8c0@lark> From: "Alan Melia" To: References: <4AFB477C.5090604@sighthound.demon.co.uk> <001501ca6326$ff28c710$0617aac0@jimdesk> <00f301ca6329$8ba907c0$0900a8c0@lark> <001901ca632a$d3356ab0$0617aac0@jimdesk> <011201ca6332$23e930c0$0900a8c0@lark> <000301ca637d$20bd9e40$0617aac0@jimdesk> Date: Thu, 12 Nov 2009 11:26:19 -0000 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2800.1106 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 X-Karma: unknown: DomainKey-Status: good (testing) X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,none Subject: LF: Re: RE: Re: RE: Re: RE: G7NKS multiple WSPR decodes! Content-Type: text/plain; charset="iso-8859-1" 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=0.0 required=5.0 tests=none 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-IP: 193.82.116.20 Hi Jim, Radio is not easy, we all learn as we go along, and are still learning. The catch is that circuit diagrams are not anything more than descriptions of a way of achieving the wanted function. They do not really show what actually is there in terms of strays, parasitic components and unexpected couplings via common impedances....you get a feel for this by experience and that is what often gives it the a nature like a "black art". It makes the succeses that more rewarding too. Stick at it and dont hesitate to ask........sometimes formulating and asking a question will help you understand the problem better, even solve it youself without further help. Alan G3NYK ----- Original Message ----- From: "James Cowburn" To: Sent: Thursday, November 12, 2009 9:47 AM Subject: LF: RE: Re: RE: Re: RE: G7NKS multiple WSPR decodes! > Hi Alan > > Thanks for the pointers here. Very useful. As it transpires, the laptop > psu is now interfering on Rx so a loop has opened up somewhere. I'm going > to dismantle the whole set up and re-wire/reroute from scratch....god help > me!! > > I should have taken up stamp collecting as a hobby! > > > > With best regards > > > Jim > > > Dr. James Cowburn > > -----Original Message----- > From: owner-rsgb_lf_group@blacksheep.org > [mailto:owner-rsgb_lf_group@blacksheep.org] On Behalf Of Alan Melia > Sent: 12 November 2009 00:25 > To: rsgb_lf_group@blacksheep.org > Subject: LF: Re: RE: Re: RE: G7NKS multiple WSPR decodes! > > Ah the dreaded laptop. Ok the isolation that is agood idea in that case you > must make sure you have some Rf grounds somewhere. Laptops seem to float > there is not reason (for the digital engineers who designed them anyway) to > put an earth on the metalwork. The RF circuitating in those leads might be > inducing hum. It might be worth trying an earth on any suitable but of the > laptop metalwork....socket pillars ?? It definitely sounds as though it is > hum getting into the PC sound system. > > Good Luck with it. > Alan G3NYK > > ----- Original Message ----- > From: "James Cowburn" > To: > Sent: Wednesday, November 11, 2009 11:58 PM > Subject: LF: RE: Re: RE: G7NKS multiple WSPR decodes! > > > > The soundcard leads are via an opto-isolator interface and the leads from > > the interface to laptop are wound on ferrite cores, approx 8 turns each > for > > tx and rx. > > > > I will check the mains psu for the dell d610 laptop as that could be > > introducing hum or picking up rf from the tx (IC-735). It might need > > ferrites on the leads to and from the SMPSU > > > > I've just turned "the wick" down on the tx/rx inputs and also the rf gain > on > > ic 735 till the needle just shifted in case it was being over-driven so > I'll > > see how that works. > > > > Not a prob when I was QRPpp but as sigs improve with dark nights I'd > noticed > > it too > > > > Thanks to John and others for heads up and suggestions > > > > With best regards > > > > > > Jim > > > > > > Dr. James Cowburn G7NKS > > -----Original Message----- > > From: owner-rsgb_lf_group@blacksheep.org > > [mailto:owner-rsgb_lf_group@blacksheep.org] On Behalf Of Alan Melia > > Sent: 11 November 2009 23:49 > > To: rsgb_lf_group@blacksheep.org > > Subject: LF: Re: RE: G7NKS multiple WSPR decodes! > > > > Hi Jim what kind of PC are you using. If a desktop are to sure it has the > > mains safety earth connected.....I have come across this problem before > some > > 3 connecter IEC moulded leads with only two wires in them!! If a laptop > then > > unless you use a radio earth that may all be floating. Sometimes it is > > necessary to use an tranformer on the audio leads to and from the PC to > gain > > isolation from the hum and noise. I use old telephone hybrid transformers > > 600ohm to 600 ohm ferrite cored. > > > > Best Wishes > > Alan G3NYK > > > > ----- Original Message ----- > > From: "James Cowburn" > > To: > > Sent: Wednesday, November 11, 2009 11:30 PM > > Subject: LF: RE: G7NKS multiple WSPR decodes! > > > > > > > Hi John > > > > > > I'll have a look see. I've noticed on strong sigs from me (few and far > > > between!) I get multiple decodes +50 and -50. I'm not aware of any > > obvious > > > mains hum if I monitor my outgoing sigs and all leads are wound on > ferrite > > > cores, but clearly something is amiss. > > > > > > I shall look into it and see what I can find > > > > > > Cheers for the heads up > > > > > > With best regards > > > > > > > > > Jim > > > > > > > > > Dr. James Cowburn > > > -----Original Message----- > > > From: owner-rsgb_lf_group@blacksheep.org > > > [mailto:owner-rsgb_lf_group@blacksheep.org] On Behalf Of John P-G > > > Sent: 11 November 2009 23:24 > > > To: rsgb_lf_group@blacksheep.org > > > Subject: LF: G7NKS multiple WSPR decodes! > > > > > > Jim. LF > > > > > > It looks like G7NKS has a 50/100Hz problem on the audio - both in TX and > > > RX directions - there are up to 3 decodes by Jim of a single station (eg > > > G3YXM), spaced by 50 & 100Hz and I see also that M0BMU is also reporting > > > multiple decodes of G7NKS with the same 50/100Hz spacing. > > > > > > Jim, have you some mains hum affecting the audio in/out of the PC? > > > > > > Cheers, > > > > > > John > > > GM4SLV > > > > > > > > > > > > > > > > > >