Return-Path: X-Spam-DCC: paranoid 1181; 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=-0.7 required=5.0 tests=BAYES_00,DNS_FROM_AHBL_RHSBL, 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 t9FHMt1A013730 for ; Thu, 15 Oct 2015 19:22:55 +0200 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1Zmm8C-0001II-Fr for rs_out_1@blacksheep.org; Thu, 15 Oct 2015 18:15:56 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1Zmm8B-0001I9-J7 for rsgb_lf_group@blacksheep.org; Thu, 15 Oct 2015 18:15:55 +0100 Received: from mta11.charter.net ([216.33.127.80]) by relay1.thorcom.net with esmtp (Exim 4.86) (envelope-from ) id 1Zmm72-0003Ck-Jo for rsgb_lf_group@blacksheep.org; Thu, 15 Oct 2015 18:15:54 +0100 Received: from imp11 ([10.20.200.11]) by mta11.charter.net (InterMail vM.8.01.05.09 201-2260-151-124-20120717) with ESMTP id <20151015171428.JHRE5815.mta11.charter.net@imp11> for ; Thu, 15 Oct 2015 13:14:28 -0400 Received: from mtaout006.msg.strl.va.charter.net ([68.114.190.31]) by imp11 with smtp.charter.net id VVEU1r0020h5dSU05VEU9p; Thu, 15 Oct 2015 13:14:28 -0400 Received: from impout006 ([68.114.189.21]) by mtaout006.msg.strl.va.charter.net (InterMail vM.9.00.020.01 201-2473-160) with ESMTP id <20151015171428.XBAJ19634.mtaout006.msg.strl.va.charter.net@impout006> for ; Thu, 15 Oct 2015 12:14:28 -0500 Received: from [192.168.1.125] ([68.118.229.27]) by impout006 with charter.net id VVEU1r00A0c6mLs01VEUvJ; Thu, 15 Oct 2015 12:14:28 -0500 X-Authority-Analysis: v=2.1 cv=Z7ZiHRhA c=1 sm=1 tr=0 a=WLV0DKOOKFWiVcf2giHCRw==:117 a=WLV0DKOOKFWiVcf2giHCRw==:17 a=hOpmn2quAAAA:8 a=N659UExz7-8A:10 a=5tzRfwI0L6MUMabQDncA:9 a=pILNOxqGKmIA:10 X-Auth-id: dzF0YWdAY2hhcnRlci5uZXQ= To: rsgb_lf_group@blacksheep.org References: <1821006912.20151014193718@chriswilson.tv> From: John Andrews Message-ID: <561FDEF7.2020503@charter.net> Date: Thu, 15 Oct 2015 13:14:31 -0400 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.3.0 MIME-Version: 1.0 In-Reply-To: X-Scan-Signature: 4d4a9e8f68fb15c54898568240f542c5 Subject: Re: LF: PA0RDT antenna near a TX? Front end OK? Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit 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: 4394 One trick that I have used on several preamps: Put a small PC-mount relay (such as those used on telephone lines) at the front end of the preamp. Connect the relay coil to the preamp power feed. Wire the relay to short the input using the normally-closed connections (i.e., powered off). Then route the preamp power through your T/R switching in the shack. This protects well against RF-swamping and nearby lightning hits. The down-side is that you have to supply the current to run the relay. German ops who hang such electronics in distant tree-tops would probably not be interested. John, W1TAG