Return-Path: Received: from mtain-dg08.r1000.mx.aol.com (mtain-dg08.r1000.mx.aol.com [172.29.65.16]) by air-dd02.mail.aol.com (v129.4) with ESMTP id MAILINDD021-86084c1df6b8141; Sun, 20 Jun 2010 07:08:40 -0400 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by mtain-dg08.r1000.mx.aol.com (Internet Inbound) with ESMTP id 78653380000B5; Sun, 20 Jun 2010 07:08:38 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1OQINF-0007D1-7g for rs_out_1@blacksheep.org; Sun, 20 Jun 2010 12:07:37 +0100 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1OQINE-0007Cs-O5 for rsgb_lf_group@blacksheep.org; Sun, 20 Jun 2010 12:07:36 +0100 Received: from mail-wy0-f171.google.com ([74.125.82.171]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1OQINB-0001wn-SY for rsgb_lf_group@blacksheep.org; Sun, 20 Jun 2010 12:07:36 +0100 Received: by wyb32 with SMTP id 32so2065228wyb.16 for ; Sun, 20 Jun 2010 04:07:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:sender:received:date :x-google-sender-auth:message-id:subject:from:to:content-type; bh=TReqXpB3oQ/05h8ROsVA/13324b0cqIX2PzVSNOPVsE=; b=p5ZiS/d9710A6oQ/wqsKpPV4JCrFcVI+gFx8W2MxsNYIwaPZmkscALrrTzcoFWPUGf OPq3JzPSf+xi+YPbzKLy1zE57FbA4DmtCPtIp6MnYc21feMf1PN9WPcCFJU+A/XrXCuo er8oV8joZchmkak2VvuJleyjO1w8L7+e6XEjY= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:date:x-google-sender-auth:message-id:subject :from:to:content-type; b=E0rO1UqphG7nEilNeyzGdvU90MksRoaBnqzSsvIDfdo57Yva+jPRE7LoHEL2oS9Jl3 0Jfx6HIakjshOoT+O6LHZA35yf9fSUr73/YNpzAYw0+Vdxad6eNh/JSTti5w06DfDndm NqDUPag1vBUo9/MBNQ1P5VDt1Re2Anc/EQMMs= MIME-Version: 1.0 Received: by 10.216.186.5 with SMTP id v5mr1717648wem.51.1277032047855; Sun, 20 Jun 2010 04:07:27 -0700 (PDT) Received: by 10.216.175.12 with HTTP; Sun, 20 Jun 2010 04:07:27 -0700 (PDT) Date: Sun, 20 Jun 2010 12:07:27 +0100 X-Google-Sender-Auth: x8WC0fv2ghijFVAiHQy9uftYOW4 Message-ID: From: Gary - G4WGT To: "LF Group (RSGB)" DomainKey-Status: good (testing) X-Spam-Score: 0.9 (/) X-Spam-Report: autolearn=disabled,HTML_10_20=0.945,HTML_MESSAGE=0.001 Subject: LF: 137.500 kHz ROS beacon Content-Type: multipart/alternative; boundary=001636416d9b9446f8048974318a X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.0 required=5.0 tests=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-SCOLL-AUTHENTICATION: mail_rly_antispam_dkim-d296.2 ; domain : gmail.com DKIM : fail x-aol-sid: 3039ac1d41104c1df6b652b7 X-AOL-IP: 193.82.116.20 X-Mailer: Unknown (No Version) --001636416d9b9446f8048974318a Content-Type: text/plain; charset=ISO-8859-1 Hi LF, Having successfully bench & on-air tested a x2 harmonic amplifier method of driving my G0MRF Class D LF transmitter, I ran a beacon last night (Saturday 19th) on 137.500 kHz. An extract from my previous e-mail description is shown at the end. Using the equipment & method described below, the ERP from my 12 metre vertical antenna was around 150mW. The mode was ROS MF-1, 100 Hz bandwidth. I received the following report from Michel, F5WK in JN18HP, a distance of 410 miles (661 kilometres) in daylight. >> Not even a faint trace on a QRSS3 spectrum but: >> RX1: 19:23 @ 5.9 Hz: 9 -37 dB >> RX1: 19:28 @ 5.4 Hz: O4WGT -34 dB >> RX1: 19:33 @ 5.4 Hz: G4WGT -31 dB The x2 harmonic low level amplifier is a simple way of driving a Class D type of transmitter which employs a divide by 2 drive chain. My limitation with multi tone drive is that my DDS VFO will only produce 2 frequencies ie. the main frequency & a CW/Rx offset which has previously limited me to 2 tones as with RTTY & DFCW modes. Please bear in mind that it will not be suitable for modes like PSK were tones are transmitted simultaneously. At the moment the 2 small PCB's are precariously lying on the desk, when I have cased them I will publish the circuit & pictures. 73 Gary - G4WGT. *********************************************** After a few days experimenting & bench testing a method of driving my G0MRF Class D Tx on the 137.000 kHz band from my linear transverter I finally constructed a harmonic amplifier producing a 274.000 kHz signal from 137.000 kHz input. An "on-air" trial was conducted resulting in a QSO with Graham G0NBD on 137.000 kHz using ROS data mode software. My thanks to Graham for his ideas & tests. The mode used was ROS MF-7. The equipment used for the QSO was as follows. Kenwood TS-440 to my LF-MF linear transverter producing the 137.000 kHz signal, followed by a tuned harmonic circuit & buffer amplifier whose output was 274.000 kHz therefore at x2 drive for the Class D Tx. The x2 signal is then divided by the Tx driver chain in the normal way to provide 137.000 kHz to the PA. This method should also work well using WSPR & other similar modes. ********************************************* --001636416d9b9446f8048974318a Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable
    Hi LF,
Having successfully bench & on-air tes= ted a x2 harmonic amplifier method of driving my G0MRF Class D LF transmit= ter, I ran a beacon last night (Saturday 19th) on 137.500 kHz.

An extract from my previous e-mail description is show= n at the end.

Using the equipment & method de= scribed below, the ERP from my 12 metre vertical antenna was around 150mW.= The mode was ROS MF-1, 100 Hz bandwidth.

I received the following report from Michel, F5WK in= JN18HP, a distance of 410 miles (661 kilometres) in daylight.
<= br>
>> Not even a faint trace on a QRSS3 spectrum but:
=
>> RX1: 19:23 @ 5.9 Hz: 9 <STOP> -37 dB
>> RX1: 19:28= @ 5.4 Hz: O4WGT <STOP> -34 dB
>> RX1: 19:33 @ 5.4 Hz: G4WG= T <STOP> -31 dB

The x2 harmonic low level= amplifier is a simple way of driving a Class D type of transmitter which= employs a divide by 2 drive chain. My limitation with multi tone drive is= that my DDS VFO will only produce 2 frequencies ie. the main frequency &a= mp; a CW/Rx offset which has previously limited me to 2 tones as with RTTY= & DFCW modes.

Please bear in mind that it will not be suitable for= modes like PSK were tones are transmitted simultaneously.

<= /div>
At the moment the 2 small PCB's are precariously lying on th= e desk, when I have cased them I will publish the circuit & pictures.<= /div>

73

Gary - G4WGT.
    ***= ********************************************
    After a few days experimenting & bench testing a method of driving= my
    G0MRF Class D Tx on the 137.000 kHz band from my linear transverter= I finally
    constructed a harmonic amplifier producing a 274.000 kHz signal from 137.0= 00
    kHz input. An "on-air" trial was conducted resulting in a= QSO with
    Graham G0NBD on 137.000 kHz using ROS data mode software.
    =A0
    My thanks to Graham for his ideas & tests.
    =A0
    The mode= used was ROS MF-7. The equipment used for the QSO was as
    follows. Kenw= ood TS-440 to my LF-MF linear transverter producing the
    137.000 kHz sig= nal, followed by a tuned harmonic circuit & buffer
    amplifier whose output was 274.000 kHz therefore at x2 drive for the Class=
    D Tx. The x2 signal is then divided by the Tx driver chain in the
    n= ormal way to provide 137.000 kHz to the PA.
    =A0
    This method should= also work well using WSPR & other similar modes.
    *********************************************
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