Return-Path: X-Spam-DCC: paranoid 1233; 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=-2.2 required=5.0 tests=BAYES_00,DNS_FROM_AHBL_RHSBL, HTML_50_60,HTML_MESSAGE,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 u3PDtT4t024215 for ; Mon, 25 Apr 2016 15:55:29 +0200 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1augum-0004MP-TV for rs_out_1@blacksheep.org; Mon, 25 Apr 2016 14:51:04 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1augum-0004MG-IG for rsgb_lf_group@blacksheep.org; Mon, 25 Apr 2016 14:51:04 +0100 Received: from omr-a013e.mx.aol.com ([204.29.186.60]) by relay1.thorcom.net with esmtps (TLSv1:DHE-RSA-AES256-SHA:256) (Exim 4.87) (envelope-from ) id 1augui-0002xo-CL for rsgb_lf_group@blacksheep.org; Mon, 25 Apr 2016 14:51:03 +0100 Received: from mtaout-aaa02.mx.aol.com (mtaout-aaa02.mx.aol.com [172.27.1.226]) by omr-a013e.mx.aol.com (Outbound Mail Relay) with ESMTP id 8F0BC3800042 for ; Mon, 25 Apr 2016 09:50:56 -0400 (EDT) Received: from [IPv6:::ffff:192.168.0.14] (ipbcc05f3c.dynamic.kabel-deutschland.de [188.192.95.60]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mtaout-aaa02.mx.aol.com (MUA/Third Party Client Interface) with ESMTPSA id 3634938000083 for ; Mon, 25 Apr 2016 09:50:55 -0400 (EDT) MIME-Version: 1.0 To: "rsgb_lf_group@blacksheep.org" From: Markus Vester Date: Mon, 25 Apr 2016 15:51:02 +0200 Importance: normal X-Priority: 3 In-Reply-To: <832578165.20160425123733@chriswilson.tv> References: <832578165.20160425123733@chriswilson.tv> x-aol-global-disposition: G DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mx.aol.com; s=20150623; t=1461592256; bh=HAf72InVFuwYlAoIv0DwxNNhi9pcSgC37b5LqxUoWhY=; h=From:To:Subject:Date:MIME-Version:Content-Type; b=kXxAOFAfSjs7qtzal7Rpnau2j1VUhex1wL6G0ptRmvUXlA3TjlH+yUpICU2GKi0ym XjBUdKMtNzcc9cih5CquNbopjdesZgkIZgsL7cHd4ehBoCJ5d5lnU4xeyuvfY/KhcO A0E3Df3hSk3+57YkiwANrl0fs6bHn1XO1gUYfg1Y= x-aol-sid: 3039ac1b01e2571e20bf704a X-AOL-IP: 188.192.95.60 X-Scan-Signature: 4998b3eda037fec4e885bebc9a2db934 Message-Id: Subject: LF: AW: Dirty signal Content-Type: multipart/alternative; boundary="_3EEC0DA8-F8FB-4D75-85C4-4F925257ADAF_" 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 Status: O X-Status: X-Keywords: X-UID: 7848 --_3EEC0DA8-F8FB-4D75-85C4-4F925257ADAF_ Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Hi Chris, as WSPR is a constant envelope signal, overdriving the TX Audio would not p= roduce intermodulation but only audio harmonics. With a fundamental near 1.= 5 kHz, the odd harmonics at 4.5 kHz etc. will be too far outside the passba= nd of an SSB transmitter to cause noticable contamination. However this may not be the whole truth: If the clipping already takes plac= e in the digital domain (i.e. before the DAC and antialias filter), we=E2= =80=99d still have the same harmonics but they could be aliased down with t= he samplerate. For example, a clipped 1.51 kHz signal contains components a= t 7f (10.57 kHz) and 9f (13.59) kHz. With 12 kHz samplerate, these could be= folded back to 1.43 and 1.59 kHz, and thus create weak unwanted sidebands = near the desired output frequency. BTW the very same effect can happen on t= he receive side when overdriving the ADC. Best 73, Markus Von: Chris Wilson Gesendet: Montag, 25. April 2016 13:38 An: rsgb_lf_group@blacksheep.org Betreff: LF: Dirty signal 25 April 2016 Had a report that my LF WSPR2 signal was dirty with massive side bands on Sunday. I had a look at my setup today found Windows had decided to up the audio level from WSPR to maximum into the TS-590 and scoping the output of the pre amp and frequency doubler before my G3YXM amp showed it looking very ropey indeed. I reset it and did a couple of normal WSPR2 transmissions interspersed with using the WSPR TUNE function, whilst watching on the G3XXM and G4WGT LF grabbers. I am no expert whatsoever, but it doesn't look bad now to me. Is this an adequate test to make and to assume things are now OK? Thanks. Screenshots are at http://www.chriswilson.tv/signals/signals.html --=20 Best regards, Chris 2E0ILY mailto:chris@chriswilson.tv My part time LF grabber is at http://www.chriswilson.tv/grabber.html --_3EEC0DA8-F8FB-4D75-85C4-4F925257ADAF_ Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset="utf-8"

 

Hi Chris,

 

as WSPR is a constant envelope signal, overdriving the TX Audio would = not produce intermodulation but only audio harmonics. With a fundamental ne= ar 1.5 kHz, the odd harmonics at 4.5 kHz etc. will be too far outside the p= assband of an SSB transmitter to cause noticable contamination.

 

However this may not= be the whole truth: If the clipping already takes place in the digital dom= ain (i.e. before the DAC and antialias filter), we=E2=80=99d still have the= same harmonics but they could be aliased down with the samplerate. For exa= mple, a clipped 1.51 kHz signal contains components at 7f (10.57 kHz) and 9= f (13.59) kHz. With 12 kHz samplerate, these could be folded back to 1.43 a= nd 1.59 kHz, and thus create weak unwanted sidebands near the desired outpu= t frequency. BTW the very same effect can happen on the receive side when o= verdriving the ADC.

 

Best 73,

Markus

 

 

 

Von: Chris Wilson
Gesendet: Montag, 2= 5. April 2016 13:38
An: rsgb_lf_group@blacksheep.org
Betreff: LF: Dirty signal=

 

2= 5 April 2016

 

 

Had a report that my LF WSPR2= signal was dirty with massive side bands

on Sunday= . I had a look at my setup today found Windows had decided to

up the audio level from WSPR to maximum into the TS-590 and sc= oping

the output of the pre amp and frequency doubl= er before my G3YXM amp

showed it looking very ropey= indeed.

 

= I reset it and did a couple of normal WSPR2 transmissions interspersed

<= p class=3DMsoNormal>with using the WSPR TUNE function, whilst watching on t= he G3XXM and

G4WGT LF grabbers. I am no expert what= soever, but it doesn't look bad

now to me. Is this = an adequate test to make and to assume things are

n= ow OK? Thanks.

 

Screenshots are at http://www.chriswilson.tv/signals/signals.html

=

 

 <= /o:p>

 

-- =

 

&nb= sp;

Best regards,

Ch= ris=C2=A0 2E0ILY=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 =C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= =C2=A0=C2=A0=C2=A0=C2=A0mailto:chris@chriswilson.tv

 

My=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0 part=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 time=C2=A0= =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 LF=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= =C2=A0 grabber=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 is=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0 at

http://www.chriswilson.tv/grabb= er.html

 

<= o:p> 

 

= = --_3EEC0DA8-F8FB-4D75-85C4-4F925257ADAF_--