Return-Path: Received: from mtain-db04.r1000.mx.aol.com (mtain-db04.r1000.mx.aol.com [172.29.64.88]) by air-me01.mail.aol.com (v129.4) with ESMTP id MAILINME014-8ba34c8a2c3a133; Fri, 10 Sep 2010 09:01:46 -0400 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-db04.r1000.mx.aol.com (Internet Inbound) with ESMTP id C86BC38000082; Fri, 10 Sep 2010 09:01:44 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1Ou0V9-0008KW-8b for rs_out_1@blacksheep.org; Fri, 10 Sep 2010 11:06:35 +0100 Received: from [83.244.159.144] (helo=relay3.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1Ou0Uy-0008JX-De for rsgb_lf_group@blacksheep.org; Fri, 10 Sep 2010 11:06:24 +0100 Received: from cavuit01.kulnet.kuleuven.be ([134.58.240.43]) by relay3.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1Otyjy-0007ei-Ly for rsgb_lf_group@blacksheep.org; Fri, 10 Sep 2010 09:13:48 +0100 Received: from smtps02.kuleuven.be (smtpshost02.kulnet.kuleuven.be [134.58.240.75]) by cavuit01.kulnet.kuleuven.be (Postfix) with ESMTP id 1FFEC7B8053 for ; Fri, 10 Sep 2010 10:13:07 +0200 (CEST) Received: from ICTS-S-HUB-N2.luna.kuleuven.be (icts-s-hub-n2.luna.kuleuven.be [10.112.9.12]) by smtps02.kuleuven.be (Postfix) with ESMTP id 082ADF3862 for ; Fri, 10 Sep 2010 10:13:07 +0200 (CEST) Received: from ICTS-S-EXC2-CA.luna.kuleuven.be ([10.112.11.13]) by ICTS-S-HUB-N2.luna.kuleuven.be ([10.112.9.12]) with mapi; Fri, 10 Sep 2010 10:13:07 +0200 X-Kuleuven: This mail passed the K.U.Leuven mailcluster From: Rik Strobbe To: "rsgb_lf_group@blacksheep.org" Date: Fri, 10 Sep 2010 10:13:06 +0200 Thread-Topic: QRS600 Thread-Index: ActQvaFot8mRsnx7SfussC1C2UhaKQAAHFXT Message-ID: References: <000a01cb50bc$73df5140$0301a8c0@your91hoehfy9g> In-Reply-To: <000a01cb50bc$73df5140$0301a8c0@your91hoehfy9g> Accept-Language: nl-NL, nl-BE Content-Language: nl-BE X-MS-Has-Attach: X-MS-TNEF-Correlator: acceptlanguage: nl-NL, nl-BE MIME-Version: 1.0 X-KULeuven-Information: Katholieke Universiteit Leuven X-KULeuven-Scanned: Found to be clean X-KULeuven-Envelope-From: rik.strobbe@fys.kuleuven.be X-Spam-Score: 1.2 (+) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001,SUBJ_ALL_CAPS=1.166 Subject: LF: RE: QRS600 Content-Type: multipart/alternative; boundary="_000_BF4A524700075746A6467658DFC7102C63821D3CFDICTSSEXC2CAlu_" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: * X-Spam-Status: No, hits=1.4 required=5.0 tests=HTML_30_40,HTML_MESSAGE, SUBJ_ALL_CAPS,TO_ADDRESS_EQ_REAL 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: 3039ac1d40584c8a2c387230 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none X-Mailer: Unknown (No Version) --_000_BF4A524700075746A6467658DFC7102C63821D3CFDICTSSEXC2CAlu_ Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable QRSS600 (=3D 10 min dot rate) requires a TX, RX and propagation stability= of 1mHz (milli Herz) so for that reason it will probably be used only on= VLF (ie. 9kHz or less) Class D transmistters on 9kHz can have an efficiency of 90% and there are= plenty of cheap power FET's or IGBT's rated >300W dissipation and > 700V= (what means you could run them right of mains voltage). A 2kW amplifier should dissipate no more than 200W, in an H-bridge amp thi= s power is spread over 4 transistors, so 50W each. 73, Rik ON7YD - OR7T ________________________________ Van: owner-rsgb_lf_group@blacksheep.org [owner-rsgb_lf_group@blacksheep.or= g] namens mal hamilton [g3kevmal@talktalk.net] Verzonden: vrijdag 10 september 2010 9:47 Aan: rsgb Onderwerp: LF: QRS600 How many transmitters could stand this duty cycle, especially the QRO vers= ions. The time needed to send a full callsign for ID could well burn the= TX out. Those using QRS 120 in the past for prolonged periods reported problems. g3kev --_000_BF4A524700075746A6467658DFC7102C63821D3CFDICTSSEXC2CAlu_ Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
QRSS600 (=3D 10 min dot rate) requir= es a TX, RX and propagation stability of 1mHz (milli Herz) so for tha= t reason it will probably be used only on VLF (ie. 9kHz or less) Class D transmistters on 9kHz can have an efficiency of 90% and there = ;are plenty of cheap power FET's or IGBT's rated >300W  dissipatio= n and > 700V (what means you could run them right of mains voltage).
A 2kW amplifier should dissipate no= more than 200W, in an H-bridge amp this power is spread over 4 transistor= s, so 50W each.
 
73, Rik  ON7YD - OR7T
 
Van: owner-rsgb_= lf_group@blacksheep.org [owner-rsgb_lf_group@blacksheep.org] namens mal ha= milton [g3kevmal@talktalk.net]
Verzonden: vrijdag 10 september 2010 9:47
Aan: rsgb
Onderwerp: LF: QRS600

How many transmitters could stand thi= s duty cycle, especially the QRO versions. The time needed to send a full= callsign for ID could well burn the TX out.
Those using QRS 120 in the past for= prolonged periods reported problems.
g3kev
 
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