Return-Path: Received: from rly-md05.mx.aol.com (rly-md05.mail.aol.com [172.20.29.143]) by air-md02.mail.aol.com (v125.7) with ESMTP id MAILINMD021-9074ad6dc2c201; Thu, 15 Oct 2009 04:24:27 -0400 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by rly-md05.mx.aol.com (v125.7) with ESMTP id MAILRELAYINMD057-9074ad6dc2c201; Thu, 15 Oct 2009 04:24:14 -0400 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1MyLc4-0004nv-Ga for rs_out_1@blacksheep.org; Thu, 15 Oct 2009 09:23:08 +0100 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1MyLc3-0004nm-Qg for rsgb_lf_group@blacksheep.org; Thu, 15 Oct 2009 09:23:07 +0100 Received: from smtp137.mail.mud.yahoo.com ([209.191.107.120]) by relay1.thorcom.net with smtp (Exim 4.63) (envelope-from ) id 1MyLaX-0006La-Kq for rsgb_lf_group@blacksheep.org; Thu, 15 Oct 2009 09:21:34 +0100 Received: (qmail 90804 invoked from network); 15 Oct 2009 08:22:48 -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:X-Priority:X-MSMail-Priority:X-Mailer:X-MIMEOLE; b=0YWMQ1X6uv7VrZ8rVUTzWu6ZiyUqE0ZMaQ9awf45bZRGC32mhPpHYaNje1mdFLLOMXv3ADRdmXdLK1WtYduEsPYZ3uN/64/CMRhEVLnXEZdZC2+6y5v2MRglVmXo166XOhiAXsZBT2Y5vTvaWK8ki36lh93r32oX9zCLa0ed93E= ; Received: from host86-134-101-34.range86-134.btcentralplus.com (ken.h.wright@86.134.101.34 with login) by smtp137.mail.mud.yahoo.com with SMTP; 15 Oct 2009 01:22:48 -0700 PDT X-Yahoo-SMTP: 9Y6mUHuswBAgnrOsukIiNdFDf95uy_Dz34nY1hlg2liKgYD952sjbg-- X-YMail-OSG: DlmASdIVM1mI8sHwZdpNOoFxZr..S1T0dKPLofIrxbRUI7UaEap7wgZKr2X12WtbA577r2Fgc54bkhQ0nP5cndSsq7RkJRcNFtGfjNBse2_ILQH7DMYWzxbMDEVVtYLPY5RAPr2EX3Kr7S1JIo_w7xH.COQiKcD9G3c1fu5XsFkjdrgx2.gbjcTSZs2zl7wWR4Z_WDi_E_k5pKeHA7.OasSUt7kYJENNcZmaP341_sRMBkwMGyQi4.fUH05xrBQLLxOFicG1pRdM6jgnXGKFMdhMSBG7Xb1G8Rfq.iX_92IAQUwjzw1Gbaonu__7pZOdWP9tUTpGWzsELQt0UR4d1PVhym_IYq1DDme9QdFSTYobKGlqGEcn_K1E9iA784qrHTPFjUqzHlIIiX_6gtjJfCbb X-Yahoo-Newman-Property: ymail-3 Message-ID: From: "Ken" To: References: <734614.81731.qm@web28102.mail.ukl.yahoo.com> Date: Thu, 15 Oct 2009 09:22:46 +0100 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.5843 X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2900.5579 DomainKey-Status: good (testing) Subject: Re: LF: MOFMT ADSL noise Content-Type: multipart/alternative; boundary="----=_NextPart_000_000E_01CA4D79.0ED349B0" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: * X-Spam-Status: No, hits=1.7 required=5.0 tests=FORGED_MUA_OUTLOOK, HTML_MESSAGE,HTML_TAG_EXISTS_TBODY 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 ------=_NextPart_000_000E_01CA4D79.0ED349B0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Hi Pete. Having a weak DSL signal, how does your 500kHz TX output affect the DS= L synchronisation?. I am in a similar position, and my 500kHz TX 100mW= ERP cw causes complete loss of synchronisation dispite copious use of= common mode filters. 73. Ken M0KHW ----- Original Message -----=20 From: M0FMT=20 To: rsgb_lf_group@blacksheep.org=20 Sent: Wednesday, October 14, 2009 1:36 PM Subject: RE: LF: MOFMT ADSL noise Hi LF group Thank you Jim and Laurence for you interest and information. Lifting this from Wikipedia ....... "With standard ADSL (annex= A), the band from 25.875 kHz to 138 kHz is used for upstream communic= ation, while 138 kHz =E2=80=93 1104 kHz is used for downstream communi= cation" .......=20 Jim is right about 136 and I find the band unaffected it is in= a dead spot in the ADSL spectrum, assuming its clean of course. I have considered filters that are advertised but since we hav= e a weak ADSL signal here, easily knocked out by Amateur TX on virtual= ly any band I felt that a filter would make things worse in that respe= ct. The reasoning being that a filter notch sitting right in the middl= e of the down stream channel would adversely affect the down load time= s which are only a tad better than dial up here. I may make something= and try it, thanks for putting that idea into the mix. It doesn't help that my antenna runs above the BT line (at rig= ht angles) to my neighbours place but having said that trials at the= furthest distance from the line using a frame ant and battery run RX= things were no better. However I did not earth the LW that I will try= next time. Thanks to all for the inputs I have filed them for reference. 73 petefmt --- On Wed, 14/10/09, Laurence BY3A-KL1X China wrote: From: Laurence BY3A-KL1X China Subject: RE: LF: MOFMT ADSL noise To: rsgb_lf_group@blacksheep.org Date: Wednesday, 14 October, 2009, 3:39 AM I had the same problem on 500 up in KL7 at home. I ended up= moving the modem to the garage where the telephone line comes out of= the ground and keeping the ADSL loaded wiring as short as possible -= then on the telephone side of the router I connected up a pair of= reasonable quality of seried ADSL filters outbound for normal telepho= ne wiring in the house. From 20 over noise I cant "see it" now as the= big antennae has been chocked off. I only use wireless around the pro= perty so it wasnt an issue. =20 Next job is to choke off the noise from the AC power line co= ming out of the ground - its awful. =20 relates to MTA Palmer Alaska solutions ADSL =20 Laurence KL 1 X =20 > From: james.moritz@btopenworld.com > To: rsgb_lf_group@blacksheep.org > Date: Tue, 13 Oct 2009 23:10:53 +0100 > Subject: Re: LF: MOFMT ADSL noise >=20 > Dear Pete, Paul-Henrik, >=20 > M0FMT wrote: > ....> Well I can only conclude it is ADSL because it is ju= st raising the=20 > noise floor it is very subtle not really identifiable like= say TV LTB, it's=20 > a mush...> >=20 > I have problems with ADSL on 500kHz at my QTH - it sounds= like "white noise"=20 > with no audible distinctive features I can detect. The noi= se can be about=20 > 10 - 20dB over the band noise here over a fairly wide band= width in the MF=20 > range. It does not seem to be a problem at 136k, perhaps= because this is in=20 > the guard band between upstream and downstream ADSL signal= s. It is easy to=20 > tell if you are experiencing noise from your own ADSL conn= ection -=20 > disconnect the incoming phone line (probably just unpluggi= ng the modem from=20 > the phone socket will be enough) and there will be a reduc= tion in noise=20 > level. Unfortunately, there also seems to be a significant= level of similar=20 > noise here from other sources, probably my neighbors' ADSL= via the overhead=20 > phone lines. >=20 > I have had some success with a noise-cancelling arrangemen= t here, where the=20 > ADSL noise is sampled using a current transformer made by= passing the=20 > incoming phone line through a ferrite core, and summed wit= h the signal from=20 > loop antennas via a variable phase-shifting and gain-adjus= ting network,=20 > which is adjusted for a null in the noise. Also, moving th= e loop around the=20 > QTH shows some positions are better than others. Actually,= life is a bit=20 > more complicated at this particular QTH, since there also= seems to be=20 > wide-band noise originating as very low-level sidebands fr= om the local=20 > broadcast stations. This requires a second noise-cancellin= g network to null=20 > noise from that direction. Also, it was necessary to inser= t a relay in=20 > series with the loading coil to disconnect the TX antenna= on receive,=20 > otherwise this coupled more noise into the receiving anten= nas. But when it=20 > is all adjusted properly, the overall noise level can be= reduced in=20 > favourable directions by about 20dB, which is worth doing. >=20 > Cheers, Jim Moritz > 73 de M0BMU=20 >=20 >=20 ---------------------------------------------------------------------- Hotmail: Trusted email with Microsoft=E2=80=99s powerful SPA= M protection. Sign up now. =20 ------=_NextPart_000_000E_01CA4D79.0ED349B0 Content-Type: text/html; charset="utf-8" Content-Transfer-Encoding: quoted-printable
Hi Pete.
Having a weak DSL signal, how does yo= ur 500kHz TX=20 output affect the DSL synchronisation?. I am in a similar position, an= d my=20 500kHz TX 100mW ERP cw causes complete loss of synchronisation dispite= copious=20 use of common mode filters.
 
73.
Ken
M0KHW
----- Original Message -----
From:=20 M0FMT=
Sent: Wednesday, October 14,= 2009 1:36=20 PM
Subject: RE: LF: MOFMT ADSL= noise

Hi LF group
 
Thank you Jim and Laurence for you interest and informati= on.
 
Lifting this from Wikipedia ....... "With standard ADSL= (annex A),=20 the band from 25.875 kHz to= 138 kHz=20 is used for upstream communication, while 138 kHz =E2=80= =93 1104 kHz=20 is used for downstream communication" ....... 
Jim is right about 136 and I find the band unaffected it= is=20 in a dead spot in the ADSL spectrum, assuming its clean= of=20 course.
I have considered filters that are advertised but since= we have a=20 weak ADSL signal here, easily knocked out by Amateur TX on vir= tually any=20 band I felt that a filter would make things worse in that resp= ect. The=20 reasoning being that a filter notch sitting right in the middl= e of the=20 down stream channel would adversely affect the down load times= which are=20 only a tad better than dial up here. I may make something and= try it,=20 thanks for putting that idea into the mix.
 
It doesn't help that my antenna runs above the BT line (a= t right=20 angles) to my neighbours place but having said that trial= s at the=20 furthest distance from the line using a frame ant and battery= run RX=20 things were no better. However I did not earth the LW tha= t I will=20 try next time.
 
Thanks to all for the inputs I have filed them for refere= nce.
 
73 petefmt
 
--- On Wed, 14/10/09, Laurence BY3A-KL1X China=20 <hellozerohellozero@hotmail.com> wrote:

From:=20 Laurence BY3A-KL1X China=20 <hellozerohellozero@hotmail.com>
Subject: RE: LF:= MOFMT ADSL=20 noise
To: rsgb_lf_group@blacksheep.org
Date: Wednesday= , 14=20 October, 2009, 3:39 AM

I had the same problem on 500 up in KL7 at home. I ended up= moving=20 the modem to the garage where the telephone line comes= out of the=20 ground and keeping the ADSL loaded wiring as short as possib= le -=20  then on the telephone side of the router  I= connected=20 up a pair of reasonable quality of seried ADSL filters = outbound=20 for normal telephone wiring in the house. From 20 over= noise I=20 cant "see it" now as the big antennae has been cho= cked off.=20 I only use wireless around the property so it wasnt an=20 issue.
 
Next job is to choke off the noise from= the AC=20 power line coming out of the ground - its awful.
 relates=20 to MTA Palmer Alaska solutions ADSL

 
Laurenc= e KL 1=20 X
 
> From: james.moritz@btopenworld.com
&g= t; To:=20 rsgb_lf_group@blacksheep.org
> Date: Tue, 13 Oct 2009= 23:10:53=20 +0100
> Subject: Re: LF: MOFMT ADSL noise
>
= > Dear=20 Pete, Paul-Henrik,
>
> M0FMT wrote:
> ...= .> Well=20 I can only conclude it is ADSL because it is just raising th= e
>=20 noise floor it is very subtle not really identifiable like= say TV LTB,=20 it's
> a mush...>
>
> I have problems= with ADSL=20 on 500kHz at my QTH - it sounds like "white noise"
>= with no=20 audible distinctive features I can detect. The noise can be= about=20
> 10 - 20dB over the band noise here over a fairly wi= de=20 bandwidth in the MF
> range. It does not seem to be= a problem=20 at 136k, perhaps because this is in
> the guard band= between=20 upstream and downstream ADSL signals. It is easy to
>= tell if=20 you are experiencing noise from your own ADSL connection -=
>=20 disconnect the incoming phone line (probably just unplugging= the modem=20 from
> the phone socket will be enough) and there wil= l be a=20 reduction in noise
> level. Unfortunately, there also= seems to=20 be a significant level of similar
> noise here from= other=20 sources, probably my neighbors' ADSL via the overhead
&g= t; phone=20 lines.
>
> I have had some success with a=20 noise-cancelling arrangement here, where the
> ADSL= noise is=20 sampled using a current transformer made by passing the
= >=20 incoming phone line through a ferrite core, and summed with= the signal=20 from
> loop antennas via a variable phase-shifting an= d=20 gain-adjusting network,
> which is adjusted for a nul= l in the=20 noise. Also, moving the loop around the
> QTH shows= some=20 positions are better than others. Actually, life is a bit >=20 more complicated at this particular QTH, since there also se= ems to be=20
> wide-band noise originating as very low-level sideb= ands from=20 the local
> broadcast stations. This requires a secon= d=20 noise-cancelling network to null
> noise from that di= rection.=20 Also, it was necessary to insert a relay in
> series= with the=20 loading coil to disconnect the TX antenna on receive,
&g= t;=20 otherwise this coupled more noise into the receiving antenna= s. But=20 when it
> is all adjusted properly, the overall noise= level can=20 be reduced in
> favourable directions by about 20dB,= which is=20 worth doing.
>
> Cheers, Jim Moritz
> 73= de M0BMU=20
>
>

Hotmail: Trusted email with Microsoft=E2=80=99s powerful SPA= M protection. Sign up no= w.=20

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