Return-Path: X-Spam-DCC: paranoid 1480; 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=-0.5 required=5.0 tests=BAYES_00,DNS_FROM_AHBL_RHSBL, HTML_50_60,HTML_MESSAGE,RATWARE_GECKO_BUILD,SPF_PASS 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 u9CJ4m4D023134 for ; Wed, 12 Oct 2016 21:04:49 +0200 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1buOmk-0006YQ-Tn for rs_out_1@blacksheep.org; Wed, 12 Oct 2016 20:01:50 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1buOmk-0006YH-Fg for rsgb_lf_group@blacksheep.org; Wed, 12 Oct 2016 20:01:50 +0100 Received: from mout02.posteo.de ([185.67.36.66]) by relay1.thorcom.net with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.87) (envelope-from ) id 1buOmh-0001GF-P9 for rsgb_lf_group@blacksheep.org; Wed, 12 Oct 2016 20:01:49 +0100 Received: from submission (posteo.de [89.146.220.130]) by mout02.posteo.de (Postfix) with ESMTPS id DA10D20A0B for ; Wed, 12 Oct 2016 21:01:46 +0200 (CEST) Received: from customer (localhost [127.0.0.1]) by submission (posteo.de) with ESMTPSA id 3svNWZ3KcYz106K for ; Wed, 12 Oct 2016 21:01:46 +0200 (CEST) Message-ID: <57FE889A.5020605@posteo.de> Date: Wed, 12 Oct 2016 21:01:46 +0200 From: DK7FC User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; de; rv:1.9.1.8) Gecko/20100227 Thunderbird/3.0.3 MIME-Version: 1.0 To: rsgb_lf_group@blacksheep.org References: <57FD3F9F.80409@lineone.net> <3018579.iHz3xfyXX4@x220> <57FE86C5.3080408@lineone.net> In-Reply-To: <57FE86C5.3080408@lineone.net> X-Scan-Signature: 40cd937fc1c5e6338b07d288cd09d087 Subject: Re: LF: Audio link Content-Type: multipart/alternative; boundary="------------070400000603080306040903" 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: 5644 Status: O X-Status: X-Keywords: X-UID: 9051 This is a multi-part message in MIME format. --------------070400000603080306040903 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Hi Hugh, But then the problem should be solved when placing the isolation audio transformer on the laptops end, so the wire does not act as an antenna. Did you try that? Maybe grounding the laptop to the mains earth is another idea, but only when using the audio transformer. 73, Stefan Am 12.10.2016 20:53, schrieb LineOne: > Hello Claudio. > > Any combination of grounding wire, or no wire, makes no difference, > the QRM is directly radiated. If you see my "shack" there's just > enough room to sit by the desk so I can't rearrange equipment any > better. "Cosy" would be a nice description. > The laptop is usually OK but it is charged by time switch about every > 2.5 hours and when fully charged, if the timer is still, on it can > wipe 10 to 20dB s/n off the signal in spite of having a linear charger. > > 73, Hugh, M0DSZ > > On 12/10/2016 15:37, Claudio Pozzi wrote: >> >> On Tuesday 11 October 2016 20:38:07 you wrote: >> >> > To avoid having laptop running in the shack, which occasionally >> >> > produces some QRM, I can send received audio from the shack to a >> >> > desktop computer in the house on a twisted telephone pair. This works >> >> > but any wire connection between shack and this desktop introduces some >> >> > spurious signals on 136khz even if I use an audio isolating >> transformer. >> >> > >> >> The AC 230 power supply in the shack and the desktop computer >> grounding wire are equipotential, share the same grounding system? >> >> 73 de Claudio ik2pii >> >> >> >> >> ---- >> ZE-Light e ZE-Pro: servizi zimbra per caselle con dominio email.it, >> per tutti i dettagli clicca qui >> >> >> Sponsor: >> Registra i domini che desideri ed inizia a creare il tuo sito web >> Clicca qui >> > --------------070400000603080306040903 Content-Type: text/html; charset=windows-1252 Content-Transfer-Encoding: 8bit Hi Hugh,

But then the problem should be solved when placing the isolation audio transformer on the laptops end, so the wire does not act as an antenna. Did you try that?
Maybe grounding the laptop to the mains earth is another idea, but only when using the audio transformer.

73, Stefan

Am 12.10.2016 20:53, schrieb LineOne:
Hello Claudio.

Any combination of grounding wire, or no wire, makes no difference, the QRM is directly radiated. If you see my "shack" there's just enough room to sit by the desk so I can't rearrange equipment any better.  "Cosy" would be a nice description.
The laptop is usually OK but it is charged by time switch about every 2.5 hours and when fully charged, if the timer is still, on it can wipe 10 to 20dB s/n off the signal in spite of having a linear charger.

73, Hugh, M0DSZ

On 12/10/2016 15:37, Claudio Pozzi wrote:

On Tuesday 11 October 2016 20:38:07 you wrote:

> To avoid having laptop running in the shack, which occasionally

> produces some QRM, I can send received audio from the shack to a

> desktop computer in the house on a twisted telephone pair. This works

> but any wire connection between shack and this desktop introduces some

> spurious signals on 136khz even if I use an audio isolating transformer.

>

 

The AC 230 power supply in the shack and the desktop computer grounding wire are equipotential, share the same grounding system?

 

73 de Claudio ik2pii

 

 




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