Return-Path: Received: from [65.33.166.167] (account ) by logan.com (CommuniGate Pro WebUser 4.0b7) with HTTP id 1734876 for ; Mon, 16 Sep 2002 20:50:14 -0400 From: "Marvin Kaye" Subject: Re: [FlyRotary]Tach sensor To: flyrotary X-Mailer: CommuniGate Pro Web Mailer v.4.0b7 Date: Mon, 16 Sep 2002 20:50:14 -0400 Message-ID: In-Reply-To: <009201c25ddc$746ec540$1702a8c0@WorkGroup> MIME-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1"; format="flowed" Content-Transfer-Encoding: 8bit Posted for "Ed Anderson" : John I am using engine tach rpm and just dividing by "2" in my head for prop rpm. There are Hall effect and other "Magnetic field" sensing sensors that are frequently used to drive ignition systems off of crank shafts (or distributor shafts). However, in any case you would need a circuit that would take the eccentric shaft rpm and "divide" by 2.17 or 2.85 as the case may be for prop rpm. A divided by 2 circuit would be easy using a Flip Flop. chip but then easy to divide by 2 in your head. Ed Anderson > Are you 13B flyers using engine tach, or is there some way to get a tach to > read prop rpm? I've heard there's an electronic sensor which reads a passing > magnet, but I havent found one yet.