X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from EXHUB003-2.exch003intermedia.net ([207.5.74.29] verified) by logan.com (CommuniGate Pro SMTP 5.2.14) with ESMTPS id 3742810 for flyrotary@lancaironline.net; Thu, 02 Jul 2009 13:08:22 -0400 Received-SPF: none receiver=logan.com; client-ip=207.5.74.29; envelope-from=jwhaley@datacast.com Received: from EXVMBX003-5.exch003intermedia.net ([207.5.74.45]) by EXHUB003-2.exch003intermedia.net ([207.5.74.29]) with mapi; Thu, 2 Jul 2009 10:07:44 -0700 From: Jeff Whaley To: Rotary motors in aircraft Date: Thu, 2 Jul 2009 10:07:43 -0700 Subject: RE: [FlyRotary] Re: frustrating couple of days Thread-Topic: [FlyRotary] Re: frustrating couple of days Thread-Index: Acn7NeOJtLJB2j/8SU2KOePDHQyKtwAALF+A Message-ID: References: In-Reply-To: Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: acceptlanguage: en-US Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 I believe the ground for the controller unit is made through the DB15 wire = harness to the EC2; by moving the A/B switch you will have lengthened this = ground loop ... maybe try a wire from Controller PCB common to ground of re= mote A/B switch. Is it possible for you to put the A/B switch back to original position? Jeff -----Original Message----- From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Beh= alf Of Ed Anderson Sent: Thursday, July 02, 2009 12:53 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: frustrating couple of days Mike, per discussion about possible de-bouncing problem. Might try stickin= g a 0.01 ufd capacitor from your Controller Switch to Ground - just to eliminate debouncing as the potential problem. Ed Ed Anderson Rv-6A N494BW Rotary Powered Matthews, NC eanderson@carolina.rr.com http://www.andersonee.com http://www.dmack.net/mazda/index.html http://www.flyrotary.com/ http://members.cox.net/rogersda/rotary/configs.htm#N494BW http://www.rotaryaviation.com/Rotorhead%20Truth.htm -----Original Message----- From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Mike Wills Sent: Thursday, July 02, 2009 12:09 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: frustrating couple of days Minor correction. Its not that I'm only seeing a problem with the B=20 controller. Its that it appears that the problem occurs when I switch to B,= =20 but in the 2 cases where the staging point was corrupted, the corrupt data= =20 was on the A controller. I've been all through the power and ground system. Multiple times. When I=20 first noted the problem and emailed Tracy about it he suspected ground=20 noise. After describing my electrical system to him he made two suggestions= : 1) I implemented a single point ground even though I have a metal airframe= . I wanted to avoid ground currents getting into the radio and intercom. Due= =20 to CG issues my batteries ended up in the baggage compartment so the ground= =20 connection from the batteries to the single point ground ended up being=20 about 8' of #0 cable. Tracy recommended eliminating this cable and tying th= e battery ground terminals to chassis ground as close as possible to the=20 batteries. I've done this. 2) My ignition coils were also connected to the single point ground through= =20 about 3' of #14 wire. Tracy indicated that the coils are the greatest=20 potential noise makers on the airplane and recommended grounding this to th= e airframe or engine block as close as possible to the coils. I've done this. I've reviewed all of my wiring to make sure that things that should be=20 shielded are and to be sure that noisy wires are seperated from sensitive=20 ones. There were no obvious problems found in my original install in this=20 regard, but I did move a couple of wires to gain even more seperation. So as I said, I believe the power and ground system in the airplane are=20 sound. I doubt that remoting the A/B switch, or something wrong with the=20 switch itself, is what is causing this, but I do believe that something is= =20 going on in the act of switching from A to B that is causing the problem.=20 I'll try to force it in my testing today. Mike Wills RV-4 N144MW ----- Original Message -----=20 From: "thomas walter" To: "Rotary motors in aircraft" Sent: Thursday, July 02, 2009 7:26 AM Subject: [FlyRotary] Re: frustrating couple of days Ed, Odd electrical trivia. Older eeproms were rated at 3.3V, so below 2.7V=20 they ignored any read or write information. We had a uC that would start "jabbering" on the data and clock lines when=20 power was caming up. Since reset occurred once power was good, it was=20 never an issue. Problem is the eeprom manufactures started shipping parts= =20 that were functional from 1.8V to 3.3V. So once power was at 1.7V, it=20 accepted writes, corrupting the eeprom. Just to drive the engineers crazy=20 only some lots and some devices 'jibbered' away. Yes, amazing I still hav= e any hair left. :) That is pretty rare, but has happened. Yes, Mike -- Interesting you're only seeing an issue with the "B"=20 controller. Still triple check the power, grounds, and rest of the=20 connections. > Since the fuel map is stored in non-volute memory, it's hard to figure ou= t > how it is being re-written or destroyed. Normally (as you know) access to= =20 > EEPROM on a chip is a rather non-trivial process. Since the A and B=20 > controller are two different chips, I suppose there could be a problem=20 > with the B chip - but, while that does happen, it's pretty rare. Have not= =20 > had one myself (yet). -- Homepage: http://www.flyrotary.com/ Archive and UnSub:=20 http://mail.lancaironline.net:81/lists/flyrotary/List.html -- Homepage: http://www.flyrotary.com/ Archive and UnSub: http://mail.lancaironline.net:81/lists/flyrotary/List.html __________ Information from ESET NOD32 Antivirus, version of virus signatur= e database 3267 (20080714) __________ The message was checked by ESET NOD32 Antivirus. http://www.eset.com =20 __________ Information from ESET NOD32 Antivirus, version of virus signatur= e database 3267 (20080714) __________ The message was checked by ESET NOD32 Antivirus. http://www.eset.com =20 -- Homepage: http://www.flyrotary.com/ Archive and UnSub: http://mail.lancaironline.net:81/lists/flyrotary/List.= html