Return-Path: X-Spam-DCC: paranoid 1481; 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=-1.9 required=5.0 tests=BAYES_00,DNS_FROM_AHBL_RHSBL, HTML_MESSAGE,PLING_QUERY,SPF_PASS,UNPARSEABLE_RELAY 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 uA3Hfvl4028968 for ; Thu, 3 Nov 2016 18:41:58 +0100 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1c2LxU-0006JM-6a for rs_out_1@blacksheep.org; Thu, 03 Nov 2016 17:37:48 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1c2LxT-0006J6-CR for rsgb_lf_group@blacksheep.org; Thu, 03 Nov 2016 17:37:47 +0000 Received: from nm22-vm6.bullet.mail.ir2.yahoo.com ([212.82.97.12]) by relay1.thorcom.net with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.87) (envelope-from ) id 1c2LxQ-0008FR-JE for rsgb_lf_group@blacksheep.org; Thu, 03 Nov 2016 17:37:46 +0000 X-DKIM-Result: Domain=yahoo.co.uk Result=Good and Known Domain DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yahoo.co.uk; s=s2048; t=1478194663; bh=Sc7Z2oKjtp6s2GopGSFN5YOuDDuo1elMRf3oce7ccAo=; h=Date:From:Reply-To:To:In-Reply-To:References:Subject:From:Subject; b=Qvkf3tNyJOis4zb+R2x6v+wm4FrO5AeRIUjNvBW+MiHxZtqsUvagcI16NiZAL+mBVmDdEXw6ovs/ErHvme4BmByrJC5PpUrDC9Vvn28vDY210ZdlPnlQBAhM4Bdexd6yVy5QmDleLzsdB14Leh0uYRsvSEILbKhmfdHSMCFBtOI97euYzO3fo89kejK8tjLb+gLhck4zPmSIlZiPe3wdbiqobJHnVhhaSozGeFaAZCE10vg8WirGPCLJgqG5+wYcFQ2zE/KjkB3Y8AFuHEiEnXNLFmjOh7XUNnpw46TULoACXe9VxHEhzEmvn2kLm2iaJ5bD7LeymWVP4nU3mZ0CGQ== Received: from [212.82.98.62] by nm22.bullet.mail.ir2.yahoo.com with NNFMP; 03 Nov 2016 17:37:43 -0000 Received: from [212.82.98.73] by tm15.bullet.mail.ir2.yahoo.com with NNFMP; 03 Nov 2016 17:37:43 -0000 Received: from [127.0.0.1] by omp1010.mail.ir2.yahoo.com with NNFMP; 03 Nov 2016 17:37:43 -0000 X-Yahoo-Newman-Property: ymail-3 X-Yahoo-Newman-Id: 403323.7867.bm@omp1010.mail.ir2.yahoo.com X-YMail-OSG: pEMvknMVM1nQh1gKkop.EkSHWqom4laC2gi1y6YLqn3vLc1sIB13pRgjasrknED AWi7y5SdGJkAvme6HNwE7gpLnnc05e162c6UhIjavciuOUH3XGa5gS0HRzbSlE.VlraQeni5X.hr fhMNc0BFxPKCdfs59SUOwrihCfr3tKKxBVJ6IICwEj6PfhFx5LeKrvDJJSROsmz74YnY8ZmsgP2D dUZA101ntkDK1zPIO0JU9D.VJj0dgU1RGpOv07lvS7CKL2z8G86ag6MufTjoSTu170AVnacA8P_u vl.JYpjF2bayu6HKnP2941M2hayDV0sPrhnG5CHUJtlUJMMkJgFLWLKzq17oMgDQ07zdhIPYGlo1 8MdPMghIOqBy7oj5fMlYXHZY6wSFet5tGmt9QtZJ8B0jTHZdRvR6tQSCi2vzqTGXb2Attx7TYqLo kA_I8RXCX.DMfYR5bbG3ze8lXK_nv2yUmdpwdHbteTn5c7M0wUMz2tGukZEd.xqNcYgXGn6H7B1m G0rSTqiqNCiZSJKCnxu7tCgBj4xB8XLHDyhk- Received: from jws700049.mail.ir2.yahoo.com by sendmailws107.mail.ir2.yahoo.com; Thu, 03 Nov 2016 17:37:43 +0000; 1478194663.006 Date: Thu, 3 Nov 2016 17:37:42 +0000 (UTC) From: David Hine To: "rsgb_lf_group@blacksheep.org" Message-ID: <1347108937.1193383.1478194662511@mail.yahoo.com> In-Reply-To: References: <581B3A1F.5060609@posteo.de> <1127299165.1072437.1478190721402@mail.yahoo.com> MIME-Version: 1.0 X-Scan-Signature: bb953ecadee360a40f72202c1637b86b Subject: Re: LF: Smart noise cancelling?!? Content-Type: multipart/alternative; boundary="----=_Part_1193382_1481745263.1478194662508" 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 Content-Length: 14390 Status: O X-Status: X-Keywords: X-UID: 9373 ------=_Part_1193382_1481745263.1478194662508 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Could be, but why is it much ch=C2=A0quieter than an Eton G3 using sync det= ection? From: Andy Talbot To: rsgb_lf_group@blacksheep.org=20 Sent: Thursday, 3 November 2016, 17:21 Subject: Re: LF: Smart noise cancelling?!? =20 Could it just be that it tunes in 9kHz steps? So will jump stright onto fre= quencyA low cost radio is sure to have a completely digital front end. 'jnt On 3 November 2016 at 17:14, Alan Melia wrote: Hi David, what describe (jump to frequency as you tune a station in) sounds= like a little bit of sophisticated radio electronics. It suggests that the= unit employs synchronous detection, somtimes called enhanced sideband dete= ction I think. I=C2=A0dont have details to hand but it would allow a clear = signal to be received in a much narrower receiver bandwidth than the 18kHz = of the=C2=A0bog standard diode detector usually used on cheapies. It also h= as the advantage that it greatly reduces the effects of fading (apparent ov= er-modulation) on the audio quality.=C2=A0=C2=A0It may=C2=A0sound unlikely = at first sight at that price But sophisicated MSF synching clocks are avail= able for about the same price.=C2=A0AlanG3NYK ----- Original Message ----- From: David Hine To: rsgb_lf_group@blackshe= ep.org Sent: Thursday, November 03, 2016 4:32 PM Subject: Re: LF: Smart no= ise cancelling?!?=20 Hi Stefan, Although this is a bit different, but also=C2=A0to do with no= ise, I bought a very cheap kitchen broadcast=C2=A0radio from Tesco for =C2= =A39. It has=C2=A0 Long Wave on it,=C2=A0and I am amazed it is the only LW= =C2=A0radio I have that can receive all the stations that still are on LW w= ithout any background noise=C2=A0once a station is tuned in. It can be main= s powered and next to a computer or TV, and still no=C2=A0local noise!! The= model number of this Tesco kitchen=C2=A0radio=C2=A0is RAD - 113B. On tunin= g to a station, it suddenly 'locks on' to it with a small=C2=A0'jump'. Then= the local noise totally disappears, leaving only the required LW=C2=A0prog= ramme interference free!! Why is this? -could it be the way this very cheap= radio detects the signal? If so, the detection=C2=A0method used in this ch= eap=C2=A0radio would be very useful for LF work, in which local mains noise= is always a big problem. Perhaps someone here=C2=A0also owns this Tesco=C2= =A0radio, and can answer why it is=C2=A0so quiet indoors where all my other= Long Wave (and much more expensive)=C2=A0receivers are all=C2=A0swamped by= local noise when used indoors?? I hope this is useful. Regards, David.=C2= =A0=C2=A0 From: DK7FC To: "rsgb_lf_group@blacksheep.org" =20 Sent: Thursday, 3 November 2016, 13:22 Subject: LF: Smart noise cancelling?!? =20 Hi all, Last night i thought a bit about noise cancelling on LF/VLF. Depending=20 on the band and distance and strength of the QRN, different settings for=20 a noise blanker are used, or optimal. Different rise times, treshold=20 levels and so on. I thought about propagation changes and different shapes of QRN bursts=20 in the time domain, requiring different blanker settings. Is it possible to program an 'intelligent' noise blanking system that is=20 evaluating the input spectrum, looking at the shape/type of a sferic and=20 automatically sets individual dynamic noise blanker parameters for each=20 burst? Or do i miss something here? Just a thought. I guess i'm not the first one who has this idea :-) 73, Stefan =20 ------=_Part_1193382_1481745263.1478194662508 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
Could be, but why is it much ch quieter than an Eton G3 using sync de= tection?


= From: Andy Talbot <andy.g4j= nt@gmail.com>
To: r= sgb_lf_group@blacksheep.org
Sent= : Thursday, 3 November 2016, 17:21
Subject: Re: LF: Smart noise cancelling?!?

Could it just be that it tunes in 9kHz steps? So will jump stright onto fr= equency
A low cost radio is= sure to have a completely digital front end.

'jnt

=
On 3 November 2016 at 17:14, Alan Melia <alan.melia@btinternet.com> wrote:
Hi David, what describe (= jump to frequency as you=20 tune a station in) sounds like a little bit of sophisticated radio electron= ics.=20 It suggests that the unit employs synchronous detection, somtimes called=20 enhanced sideband detection I think. I dont have details to hand but i= t=20 would allow a clear signal to be received in a much narrower receiver bandw= idth=20 than the 18kHz of the bog standard diode detector usually used on chea= pies.=20 It also has the advantage that it greatly reduces the effects of fading=20 (apparent over-modulation) on the audio quality.
 
 It may sound u= nlikely at first sight at=20 that price But sophisicated MSF synching clocks are available for about the= same=20 price.
 
Alan
G3NYK
----- Original Message -----
From:=20 David=20 Hine
Sent: Thursday, November 03, 2016 = 4:32=20 PM
Subject: Re: LF: Smart noise=20 cancelling?!?

Hi Stef= an,=20 Although this is a bit different, but also to do with noise, I bough= t a=20 very cheap kitchen broadcast radio from Tesco for =C2=A39. It has&nb= sp; Long=20 Wave on it, and I am amazed it is the only LW radio I have that= can=20 receive all the stations that still are on LW without any background=20 noise once a station is tuned in. It can be mains powered and next t= o a=20 computer or TV, and still no local noise!! The model number of this = Tesco=20 kitchen radio is RAD - 113B. On tuning to a station, it suddenl= y=20 'locks on' to it with a small 'jump'. Then the local noise totally= =20 disappears, leaving only the required LW programme interference free= !!=20 Why is this? -could it be the way this very cheap radio detects the signa= l? If=20 so, the detection method used in this cheap radio would be very= =20 useful for LF work, in which local mains noise is always a big problem.= =20 Perhaps someone here also owns this Tesco radio, and can answer= why=20 it is so quiet indoors where all my other Long Wave (and much more= =20 expensive) receivers are all swamped by local noise when used= =20 indoors?? I hope this is useful. Regards, David.  

From: DK7FC=20 <selberdenk= en@posteo.de>
To: "rsgb_lf_group@blacksheep.org"=20 <rsgb_lf_group@blacksheep.org>
Sent: Thursday, 3 November=20 2016, 13:22
= Subject: LF: Smart noise=20 cancelling?!?

Hi=20 all,

Last night i thought a bit abou= t noise cancelling on LF/VLF.=20 Depending
on the band and distance and strength of the= QRN, different=20 settings for
a noise blanker are used, or optimal. Dif= ferent rise times,=20 treshold
levels and so on.
I thought= about propagation changes and=20 different shapes of QRN bursts
in the time domain, req= uiring different=20 blanker settings.

Is it possible to = program an 'intelligent' noise=20 blanking system that is
evaluating the input spectrum,= looking at the=20 shape/type of a sferic and
automatically sets individu= al dynamic noise=20 blanker parameters for each
burst?
O= r do i miss something=20 here?

Just a thought. I guess i'm no= t the first one who has this idea=20 :-)

73,=20 Stefan






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