Return-Path: X-Spam-DCC: paranoid 1233; 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=-1.0 required=5.0 tests=BAYES_00,DNS_FROM_AHBL_RHSBL, FORGED_RCVD_HELO,SPF_PASS,SUBJ_RE_NUM 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 u4LH0hGC021458 for ; Sat, 21 May 2016 19:00:43 +0200 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1b4ACC-0007ZC-J3 for rs_out_1@blacksheep.org; Sat, 21 May 2016 17:56:12 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1b4ACC-0007Z3-2c for rsgb_lf_group@blacksheep.org; Sat, 21 May 2016 17:56:12 +0100 Received: from smarthost01c.mail.zen.net.uk ([212.23.1.5]) by relay1.thorcom.net with esmtp (Exim 4.87) (envelope-from ) id 1b4ACA-0001gb-Ap for rsgb_lf_group@blacksheep.org; Sat, 21 May 2016 17:56:10 +0100 Received: from [82.70.254.222] (helo=OfficeWin7.lan) by smarthost01c.mail.zen.net.uk with esmtp (Exim 4.80) (envelope-from ) id 1b4AC9-0000xJ-7J for rsgb_lf_group@blacksheep.org; Sat, 21 May 2016 16:56:09 +0000 Date: Sat, 21 May 2016 17:56:08 +0100 From: Chris Wilson Organization: Gatesgarth Developments X-Priority: 3 (Normal) Message-ID: <12310061840.20160521175608@chriswilson.tv> To: Lawrence Galea In-Reply-To: References: <1934937394.20160518170418@chriswilson.tv> <8D8E6474-E8CF-4C87-B097-6502B8180CE3@talktalk.net> MIME-Version: 1.0 X-Originating-smarthost01c-IP: [82.70.254.222] X-Scan-Signature: a6b6ffaf48fdddf1ed5c25dc4bf03ee1 Subject: Re[2]: LF: Can LF damage a mains input filter? Content-Type: text/plain; charset=us-ascii 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 10.1.3.11 Status: O X-Status: X-Keywords: X-UID: 8139 Hello Lawrence, Thursday, May 19, 2016 Thanks to all for some great ideas and help. Time has precluded me from tearing the original amp / slitter apart, but fitting anew Labgear brand one immediately cured the problem, and i have to say that I suspect my LF activity killed it, either down the mains or down the feeder. I like the idea of a dish and a satellite feed, as does `er indoors as she seems desperate to set up yet another direct debit, this time in favour of Sky TV :( The inductor across the input sounds a good idea, and I may use it. I will perhaps have a play with my (expensively) fixed SA and tracking gen to see how one works on the bench, and learn something, hopefully. Next time I am LF'ing I will add a transformer before the loading coil, even though I get a very good match without one, in the hope it will keep RF off the feedline and out of the shack. For now I am getting no grief off the wife, at least not about the TV going on the blink, so my thanks again to you all. Best regards, Chris 2E0ILY mailto:chris@chriswilson.tv My part time LF grabber is at http://www.chriswilson.tv/grabber.html > Hello Chris. > Apart from the suggestions from others, I would suggest a small 1.5 - > 2 turn link right across the input of the amplifier. You could wind it > on say a 2mm twist drill for size. Such a coil would present a > reasonable impedance to the UHF TV signals but would effectively be a > short circuit for HF and lower VHF signals, shorting them to earth at > the amplifier input. and prevent saturation of the amplifier with your > transmitter signals. > Regards > Lawrence