Return-Path: Received: from smtp01.infoave.net ([165.166.0.26]) by ns1.olsusa.com (Post.Office MTA v3.5.3 release 223 ID# 0-64832U3500L350S0V35) with ESMTP id com for ; Tue, 2 Jan 2001 19:11:13 -0500 Received: from john ([207.144.234.138]) by SMTP00.InfoAve.Net (PMDF V5.2-33 #45322) with SMTP id <01JYFYC2VK029C11CB@SMTP00.InfoAve.Net> for lancair.list@olsusa.com; Tue, 2 Jan 2001 19:19:21 EDT Date: Tue, 02 Jan 2001 08:23:21 -0500 From: John Cooper Subject: Electrical Noise debugging To: lancair.list@olsusa.com Message-id: <3.0.5.32.20010102082321.009acd60@mail.citcom.net> X-Mailing-List: lancair.list@olsusa.com Reply-To: lancair.list@olsusa.com Mime-Version: 1.0 <<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>> << Lancair Builders' Mail List >> <<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>> >> Electric motors - such as the flap and autopilot - can send high-frequency noise back up their power supply lines and onto your avionics buss. I fixed a similar problem once where the MT prop servos were introducing noise into a StormScope. You can determine whether the problem is power-buss related by connecting your autopilot system (or flap motor) to a separate battery, not on the avionics buss. If the problem goes away, then you know where the noise is coming from and how it is getting to your avionics. If the power wiring turns out to be the problem, take the positive lead to your S-Tec (or flap motor) and wind it about ten or twenty times around a ferrite "donut". This will stop most of the noise - at least it did for me. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> LML website: http://www.olsusa.com/Users/Mkaye/maillist.html LML Builders' Bookstore: http://www.buildersbooks.com/lancair Please send your photos and drawings to marvkaye@olsusa.com. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>