Return-Path: X-Spam-DCC: paranoid 1102; 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=-0.6 required=5.0 tests=BAYES_00,DATE_IN_PAST_12_24, DNS_FROM_AHBL_RHSBL,HTML_40_50,HTML_MESSAGE 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 tAT9YRI8030348 for ; Sun, 29 Nov 2015 10:34:27 +0100 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1a2yKL-0006Tv-HR for rs_out_1@blacksheep.org; Sun, 29 Nov 2015 09:31:25 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1a2yKK-0006Tc-UL for rsgb_lf_group@blacksheep.org; Sun, 29 Nov 2015 09:31:24 +0000 Received: from out1.ip07ir2.opaltelecom.net ([62.24.128.243]) by relay1.thorcom.net with esmtp (Exim 4.86) (envelope-from ) id 1a2yJG-0002n2-I8 for rsgb_lf_group@blacksheep.org; Sun, 29 Nov 2015 09:31:23 +0000 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: A2DzCwB2xFpWPKyNH1xdGQEBAgcEAQIBAQECgj5NU2+wIY94IYVoAQMBAQKBGE0BAQEBAQEHAQEBAUABP0EQAYNiAQEBAQMIGzMeEAUFAwMRBAEBKwICOQoMCAYTCAkKh34DFgmpWYsKDYQ/CwEBAR+LUoJTgWuDNy+BFQWWVwGBKIoYg1KTL4Nlg3KCf4FoPjQBAYF9g3IBAQE X-IPAS-Result: A2DzCwB2xFpWPKyNH1xdGQEBAgcEAQIBAQECgj5NU2+wIY94IYVoAQMBAQKBGE0BAQEBAQEHAQEBAUABP0EQAYNiAQEBAQMIGzMeEAUFAwMRBAEBKwICOQoMCAYTCAkKh34DFgmpWYsKDYQ/CwEBAR+LUoJTgWuDNy+BFQWWVwGBKIoYg1KTL4Nlg3KCf4FoPjQBAYF9g3IBAQE X-IronPort-AV: E=Sophos;i="5.20,360,1444690800"; d="scan'208,217";a="323350865" Received: from host-92-31-141-172.as13285.net (HELO malPC) ([92.31.141.172]) by out1.ip07ir2.opaltelecom.net with SMTP; 29 Nov 2015 09:40:23 +0000 Message-ID: From: "mal hamilton" To: References: In-Reply-To: Date: Sat, 28 Nov 2015 18:23:09 -0000 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal Importance: Normal X-Mailer: Microsoft Windows Live Mail 15.4.3555.308 X-MimeOLE: Produced By Microsoft MimeOLE V15.4.3555.308 X-Scan-Signature: e2fb1a5df1e2bc3146a6f486b4640b03 Subject: Re: LF: Class E PA design Content-Type: multipart/alternative; boundary="----=_NextPart_000_03D9_01D12A09.D5B97B30" 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: 5419 This is a multi-part message in MIME format. ------=_NextPart_000_03D9_01D12A09.D5B97B30 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable I have used home brew class E and never had a problem, more critical to = set up than D but more reliable having got it on the nose, g3kev From: Andy Talbot=20 Sent: Saturday, November 28, 2015 2:54 PM To: rsgb_lf_group@blacksheep.org ; rsgb_lf_group@yahoogroups.co.uk=20 Subject: LF: Class E PA design There was a discussion a while ago about ththe PA design used here http://www.gw3uep.ukfsn.org/100W_QTX/100WTX/PA_pa.gif and Alan amde = the comment, I think that teh series capacitor at 1uF looked = suspiciously large to be part of a tank circuit for a Class E = transmitter. Well... I've just been playing around with my spreadsheet for Class E = stages with a built in series-L shunt-C match at the output. = http://www.g4jnt.com/DownLoad/classe_match.xls For a range of transformed impedances there are two configurations that = you can end up with. The reactance of the series L part of the match = can be absorbed into the tank coil, increasing its value, OR, it can = be absorbed into the series C DECREASING its value. Using this latter = solution, there will (usually) come a point with suitable choice of = tank Q where the reactance of the matching L exactly equals that of the = tank capacitor, making this disappear. =20 That is almost certainly what has happened in GW3UEP's design. There = are also a range of values where Xc tank is less than Xl match so it can = never be absorbed, and only the one solution is possible - that of = adding it to the tank inductor. To do this you have to first get a working network with some arbitrary Q = chosen, and a valid output match for your optimum power output etc. Then = adjust the tank Q value while watching the resulting two possible values = shown as C2 on the spreadsheet. As Q is altered, one will move toward = infinity then disappear completely. Andy G4JNT ------=_NextPart_000_03D9_01D12A09.D5B97B30 Content-Type: text/html; charset="utf-8" Content-Transfer-Encoding: quoted-printable
I have used home brew class E and never had a problem, more = critical to set=20 up than D but more reliable having got it on the nose,
g3kev
 
 
Sent: Saturday, November 28, 2015 2:54 PM
To: rsgb_lf_group@blacksheep.org= ; rsgb_lf_group@yahoogroups= .co.uk=20
Subject: LF: Class E PA design
 
There was a discussion a while ago about ththe PA design = used=20 here
http://www.gw3uep.ukfsn.org/100W_QTX/100WTX/PA_pa.gif=    =20 and Alan amde the comment, I think that teh series capacitor at 1uF = looked=20 suspiciously large to be part of a tank circuit for a Class E=20 transmitter.
 
Well...   I've just been playing around with my = spreadsheet for=20 Class E stages with a built in series-L shunt-C match at the output. http://www.g4jnt.com/DownLoad/classe_match.xls
 
For a range of transformed impedances there are two configurations = that you=20 can end up with.    The reactance of the series L part of = the=20 match can be absorbed into the tank coil, increasing its value, = OR,  =20 it can be absorbed into the series C DECREASING its value.  Using = this=20 latter solution, there will (usually)  come a point with suitable = choice of=20 tank Q where the reactance of the matching L exactly equals that of the = tank=20 capacitor, making this disappear.  
 
That is almost certainly  what has happened in GW3UEP's = design. =20 There are also a range of values where Xc tank is less than Xl match so = it can=20 never be absorbed, and only the one solution is possible - that of = adding it to=20 the tank inductor.
 
To do this you have to first get a working network with some = arbitrary Q=20 chosen, and a valid output match for your optimum power output etc. Then = adjust=20 the tank Q value while watching the resulting two possible values shown = as C2 on=20 the spreadsheet.  As Q is altered, one will move toward infinity = then=20 disappear completely.
 
Andy  G4JNT
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