Return-Path: Received: from mtain-dh07.r1000.mx.aol.com (mtain-dh07.r1000.mx.aol.com [172.29.65.27]) by air-mf04.mail.aol.com (v126.13) with ESMTP id MAILINMF044-8be84b4f0f3d9f; Thu, 14 Jan 2010 07:34:05 -0500 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by mtain-dh07.r1000.mx.aol.com (Internet Inbound) with ESMTP id 36246380001A9; Thu, 14 Jan 2010 07:34:03 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1NVOsh-0007q3-U2 for rs_out_1@blacksheep.org; Thu, 14 Jan 2010 12:32:55 +0000 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1NVOsh-0007pu-Cw for rsgb_lf_group@blacksheep.org; Thu, 14 Jan 2010 12:32:55 +0000 Received: from mail-fx0-f213.google.com ([209.85.220.213]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1NVOse-0000K5-Iv for rsgb_lf_group@blacksheep.org; Thu, 14 Jan 2010 12:32:55 +0000 Received: by fxm5 with SMTP id 5so2849707fxm.29 for ; Thu, 14 Jan 2010 04:32:46 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=googlemail.com; s=gamma; h=domainkey-signature:mime-version:received:in-reply-to:references :date:message-id:subject:from:to:content-type; bh=n+zZwLtPOhy1XugDJa3dFvaeGnykzePFrQWk8KmCaEE=; b=ncAKUw31+3FswOD9Y8ObV1+VuPAyJ4f3A16w5sU/r2tMICnn4dve41gnXWwWunO3Z/ WbearD5lzaQwCw8ZCDrfEdEbHimrdTjrB4p5wtM/g0Ofx6b7Ow9mQ7/cIy8w+atLyAL9 daSGzd1OPIpuqRomZyh59buDzvJhLmAlqYuBk= DomainKey-Signature: a=rsa-sha1; c=nofws; d=googlemail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; b=qwZs2gcc/QD0ZgAh7dHViPkkmpQ5toRIffbuO7u26/wALcSMNVGbyraf2G0kuJ7U97 JmPi+1zjdufTm6VNNxGxQZy6No1sE2ybHcqlEchYZNSOh1l1DemD18OYQlIUK8zCkMpU 35PnWzS4koy6J8SrR3G4j7KZYxJyHV7RSwhGE= MIME-Version: 1.0 Received: by 10.239.189.76 with SMTP id s12mr67138hbh.111.1263472365025; Thu, 14 Jan 2010 04:32:45 -0800 (PST) In-Reply-To: <9afca2641001140408o9e58f8g36272480eb115958@mail.gmail.com> References: <1f0624b91001131347i18ff85bbxb5977cdcb3c438f5@mail.gmail.com> <20100113220536.23ff9c6e@opc1> <20100113232415.j3jn4brkyqs4gg0s@webmail6.kuleuven.be> <1f0624b91001140306k7eff5b4cn9ae73cb5cc6a37fc@mail.gmail.com> <9afca2641001140408o9e58f8g36272480eb115958@mail.gmail.com> Date: Thu, 14 Jan 2010 12:32:44 +0000 Message-ID: From: Andy Talbot To: rsgb_lf_group@blacksheep.org X-Karma: unknown: DomainKey-Status: good (testing) X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001 Subject: Re: LF: 500khz WSPR drift Content-Type: multipart/alternative; boundary=0016e64c2d36803b6d047d1f1513 X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.6 required=5.0 tests=HTML_20_30, HTML_FONTCOLOR_UNSAFE,HTML_MESSAGE 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-global-disposition: G x-aol-sid: 3039ac1d411b4b4f0f3b23c8 X-AOL-IP: 193.82.116.20 X-Mailer: Unknown (No Version) --0016e64c2d36803b6d047d1f1513 Content-Type: text/plain; charset=ISO-8859-1 If you are able to derive the transverter LO from the transverter's master oscillator do so. That way errors will be cancelled out and any frequency drift will be now be in direct proportion to the final output frequency, rather than being that associated with any arbitrarily high IF. Just an example: The master oscillator in the IC746 is at 30MHz, so transverting from 30.5MHz would be an option in this case. But one could just as easily divide this by 2 first and transvert from 15.5MHz. Andy www.g4jnt.com This email has been scanned for damaging side-effects by the health and safety police, is guaranteed to contain no substances hazardous to health, but may contribute to dissolving the nether and polar regions 2010/1/14 Roger Lapthorn > My own QRP transverter goes from 28MHz down to 500kHz and this drifts about > 40Hz before settling as the oscillator warms, so I have to be on-hand to > adjust the dial setting in the first 30 minutes. I should leave the > oscillator running all the time or have this on for 30 minutes before I > start TXing. > > At 50MHz drift would be worse. Also, I'm not sure what ambient temperature > LA3EQ has got, but I bet it is cold, so his drift might be even greater as > his transverter (higher power than mine) warms up more over a larger > temperature range. > > 73s > Roger G3XBM > > 2010/1/14 Gary - G4WGT > > Hi guys, >> >> Yes it was LA3EQ, started getting decodes as the drift flattened out. 50 >> MHz to 500 kHz is a long way to transvert, I use 4 MHz & as far as I am >> aware no drift problems after half an hour or so warm up. >> >> Thanks all the comments. >> >> Gary - G4WGT. >> >> 2010/1/13 James Moritz >> >> Dear LF Group, >>> >>> ...The perils of having a 50MHz -> 500kHz transverter! 3.5MHz would be a >>> better IF frequency from the drift point of view. >>> >>> Cheers, Jim Moritz >>> 73 de M0BMU >>> >>> ----- Original Message ----- From: "Rik Strobbe" < >>> Rik.Strobbe@fys.kuleuven.be> >>> To: >>> Sent: Wednesday, January 13, 2010 10:24 PM >>> Subject: Re: LF: 500khz WSPR drift >>> >>> >>> >>> over the past 12 hours I had 51 spots of LA3EQ, frequency ranging from >>>> 503848 to 503885 >>>> >>>> 73, Rik >>>> >>> >>> >>> >> > > > -- > > http://g3xbm-qrp.blogspot.com/ > http://www.g3xbm.co.uk > http://www.youtube.com/user/G3XBM > G3XBM GQRP 1678 ISWL G11088 > --0016e64c2d36803b6d047d1f1513 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable
If you are able to derive the transverter LO from the transverter'= ;s master oscillator do so.=A0 That way=A0errors will be cancelled out and= =A0any frequency=A0drift will be now be in direct proportion to the final= output frequency, rather than being that associated with any arbitrarily= high IF.
=A0
Just an example:
The master oscillator in the IC746 is at 30MHz, so transverting from= 30.5MHz would be an option in this case.=A0 But one could just as easily= divide this by 2 first and transvert from 15.5MHz.
=A0
Andy
www.g4jnt.com

Thi= s email has been scanned for damaging side-effects by the health and safet= y police, is guaranteed to contain no substances hazardous to health, but= may contribute to dissolving the nether and polar regions


2010/1/14 Roger Lapthorn <= rogerlapthorn@gmail.com>=
My own QRP transverter goes= from 28MHz down to 500kHz and this drifts about 40Hz before settling as= the oscillator warms, so I have to be on-hand to adjust the dial setting= in the first 30 minutes. I should leave the oscillator running all the ti= me or have this on for 30 minutes before I start TXing.

At 50MHz drift would be worse. Also, I'm not sure what ambient tem= perature LA3EQ has got, but I bet it is cold, so his drift might be even= greater as his transverter (higher power than mine) warms up more over a= larger temperature range.

73s
Roger G3XBM

2010/1/14 Gary - G4WGT <g4wgt@tiscali.co.uk= >=20

Hi guys,=20

Yes it was LA3EQ, =A0started getting decodes as the drift flattened= out. 50 MHz to 500 kHz is a long way to transvert, I use 4 MHz & as= far as I am aware no drift problems after half an hour or so warm up.

Thanks all the comments.

Gary - G4WGT.

2010/1/13 James Moritz <james.mori= tz@btopenworld.com>=20

Dear LF Group,
...The perils of having a 50MHz -> 500kHz transverter! 3.5MHz woul= d be a better IF frequency from the drift point of view.

Cheers, Jim Moritz
73 de M0BMU

----- Original Message -----= From: "Rik Strobbe" <Rik.Strobbe@fys.kuleuven.be>
To: <<= a href=3D"mailto:rsgb_lf_group@blacksheep.org" target=3D"_blank">rsgb_lf_g= roup@blacksheep.org>
Sent: Wednesday, January 13, 2010 10:24 PM
Subject: Re: LF: 500khz WSPR= drift=20



over the past 12= hours I had 51 spots of LA3EQ, frequency ranging from 503848 to 503885
73, Rik





--

http://g3xbm-qrp.blogspot.com/
http://www.g3xbm.co.= uk
= http://www.youtube.com/user/G3XBM
G3XBM =A0 =A0GQRP 1678 =A0 =A0 = =A0ISWL G11088

--0016e64c2d36803b6d047d1f1513--