Return-Path: X-Spam-DCC: paranoid 104; 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=-0.2 required=5.0 tests=BAYES_00,DNS_FROM_AHBL_RHSBL, HTML_40_50,HTML_MESSAGE,RATWARE_GECKO_BUILD 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 t9LJqgNO006288 for ; Wed, 21 Oct 2015 21:52:42 +0200 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1ZozNB-0001rV-Ph for rs_out_1@blacksheep.org; Wed, 21 Oct 2015 20:48:33 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1ZozNB-0001rM-Fc for rsgb_lf_group@blacksheep.org; Wed, 21 Oct 2015 20:48:33 +0100 Received: from smtpout.karoo.kcom.com ([212.50.160.34]) by relay1.thorcom.net with esmtp (Exim 4.86) (envelope-from ) id 1ZozM7-0002NY-AJ for rsgb_lf_group@blacksheep.org; Wed, 21 Oct 2015 20:48:32 +0100 X-IronPort-AV: E=Sophos;i="5.20,178,1444690800"; d="scan'208,217";a="137365778" Received: from unknown (HELO [127.0.0.1]) ([109.176.196.66]) by smtpout.karoo.kcom.com with ESMTP; 21 Oct 2015 20:47:10 +0100 Message-ID: <5627EBBF.7010009@lineone.net> Date: Wed, 21 Oct 2015 20:47:11 +0100 From: LineOne User-Agent: Mozilla/5.0 (Windows NT 5.1; rv:31.0) Gecko/20100101 Thunderbird/31.1.2 MIME-Version: 1.0 To: rsgb_lf_group@blacksheep.org References: <562757A3.2080109@lineone.net> In-Reply-To: X-Scan-Signature: 1273381c241b4bc851b7e848e0897dc9 Subject: Re: LF: SSB modulation for WSPR Content-Type: multipart/alternative; boundary="------------070102000003020705060602" 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 10.1.3.10 Status: O X-Status: X-Keywords: X-UID: 4566 This is a multi-part message in MIME format. --------------070102000003020705060602 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Unequal in amplitude Andy. the cure was simple but ridiculous. I had set the internal preset balance with the I & Q gain pots about halfway but what I didn't check was that I & Q remained identical at different gain settings. In using many second-hand components, including a 2-gang 10k log pot on the I & Q input which came from a sound mixer I made about 20 years ago. Since that time I'd forgotten that these pots were log/antilog as they were stereo pan pots. Say no more. Hugh On 21/10/2015 11:13, Andy Talbot wrote: > Need to ask the obvious - is the frequency recorded in Joe's spots the > actual one you were transmitting on? Exactly, spot on, to the Hz ? > When you say I and Q are "somewhat different", do you mean, the wrong > way round, or unequal amplitued, or not in quadrature. All would > contribute to a component on the wrong sideband and / or frequency as > well as the correct one > > Seems a bit odd that your one actual decoded spot was quite weak copy > at a respectable distance. Judging from my dual mode transmission > the other day, there are quite a few monitoring stations closer. > > > Andy > > On 21 October 2015 at 10:15, LineOne > wrote: > > So far the only person to decode my WSPR transmissions is Joe, DF2JP. > > I made a drive unit for 136kHz to utilise 4 different methods of > modulation including quadrature switching for SSB. Having just > discovered that a fault caused the I and Q channels to be somewhat > different I wondered what the effect would be and why Joe was the > only one to decode it? > > The carrier frequency is never more than 0.8Hz out, time is spot > on via GMT (UTC) and the sound card is perfectly accurate so > receive decoding is good. > > Hugh, M0DSZ. > > (P.S. I have no intention of signing up to Yahoo). > > > > --------------070102000003020705060602 Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: 8bit Unequal in amplitude Andy. the cure was simple but ridiculous. I had set the internal preset balance with the I & Q gain pots about halfway but what I didn't check was that  I & Q remained identical at different gain settings. In using many second-hand components, including a 2-gang 10k log pot on the I & Q input which came from a sound mixer I made about 20 years ago. Since that time I'd forgotten that these pots were log/antilog as they were stereo pan pots. Say no more.

Hugh

On 21/10/2015 11:13, Andy Talbot wrote:
Need to ask the obvious - is the frequency recorded in Joe's spots the actual one you were transmitting on?  Exactly, spot on, to the Hz ?
When you say I and Q are "somewhat different",  do you mean, the wrong way round, or unequal amplitued, or not in quadrature. All would contribute to a component on the wrong sideband and / or frequency  as well as the correct one

Seems a bit odd that your one actual decoded spot was quite weak copy at a respectable distance.   Judging from my dual mode transmission the other day, there are quite a few monitoring stations closer.


Andy

On 21 October 2015 at 10:15, LineOne <dhchurch@lineone.net> wrote:
So far the only person to decode my WSPR transmissions is Joe, DF2JP.

I made a drive unit for 136kHz to utilise 4 different methods of modulation including quadrature switching for SSB. Having just discovered that a fault caused the I and Q channels to be somewhat different I wondered what the effect would be and why Joe was the only one to decode it?

The carrier frequency is never more than 0.8Hz out, time is spot on via GMT (UTC) and the sound card is perfectly accurate so receive decoding is good.

Hugh, M0DSZ.

(P.S. I have no intention of signing up to Yahoo).





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