---------------------------------------------------------- Yak-List Digest Archive --- Total Messages Posted Wed 04/03/13: 4 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 06:47 AM - MGL digital tach on an M-14 (Walt Murphy) 2. 08:38 AM - Re: MGL digital tach on an M-14 (Robin Hou) 3. 10:18 AM - Re: MGL digital tach on an M-14 (Gill Gutierrez) 4. 08:05 PM - Re: MGL digital tach on an M-14 (Walter Lannon) ________________________________ Message 1 _____________________________________ Time: 06:47:20 AM PST US From: Walt Murphy Subject: Yak-List: MGL digital tach on an M-14 Does anyone have any experience in installing an MGL digital tach/manifold press gauge in an aircraft with an M-14? The installer added resistors and trimmed the instrument but it's still not correct...close but maybe 150 RPM off compared to a strobe tach on the prop. Any info on the correct resistor or ?? Would be most helpful thanks, Walt Murphy Reno ________________________________ Message 2 _____________________________________ Time: 08:38:12 AM PST US From: Robin Hou Subject: Re: Yak-List: MGL digital tach on an M-14 No experience with MGL, but my GRT EIS connected to mag switch on a Huosai works great. Strobe each on your prop measures prop rpm. Digital tach connected to mags measures engine rpm. You need to account for gear reduction to verify both measurements. ________________________________ Message 3 _____________________________________ Time: 10:18:35 AM PST US From: "Gill Gutierrez" Subject: RE: Yak-List: MGL digital tach on an M-14 I use their tach and it is accurate. It could be that it needs to be programmed for the correct pulse count. The guys at MGL are always very helpful. Gill -----Original Message----- From: owner-yak-list-server@matronics.com [mailto:owner-yak-list-server@matronics.com] On Behalf Of Walt Murphy Sent: Wednesday, April 03, 2013 6:45 AM Subject: Yak-List: MGL digital tach on an M-14 Does anyone have any experience in installing an MGL digital tach/manifold press gauge in an aircraft with an M-14? The installer added resistors and trimmed the instrument but it's still not correct...close but maybe 150 RPM off compared to a strobe tach on the prop. Any info on the correct resistor or ?? Would be most helpful thanks, Walt Murphy Reno ________________________________ Message 4 _____________________________________ Time: 08:05:13 PM PST US From: "Walter Lannon" Subject: Re: Yak-List: MGL digital tach on an M-14 Walt; As Robin has noted you need to take the gear ratio into account when comparing engine to prop RPM. For the M14P the gear ratio is 0.658. For the Huosai it is 0.787. At 2900 engine RPM the M14 prop is turning at 1908 RPM. At 2350 engine RPM the Huosai prop is turning at 1850 RPM. Hope that helps. Walt -----Original Message----- From: Walt Murphy Sent: Wednesday, April 03, 2013 6:44 AM Subject: Yak-List: MGL digital tach on an M-14 Does anyone have any experience in installing an MGL digital tach/manifold press gauge in an aircraft with an M-14? The installer added resistors and trimmed the instrument but it's still not correct...close but maybe 150 RPM off compared to a strobe tach on the prop. Any info on the correct resistor or ?? Would be most helpful thanks, Walt Murphy Reno ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message yak-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Yak-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/yak-list Browse Digests http://www.matronics.com/digest/yak-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.