AeroElectric-List Digest Archive

Wed 11/22/06


Total Messages Posted: 31



Today's Message Index:
----------------------
 
     0. 01:02 AM - Please Make a Contribution to Support Your Lists... (Matt Dralle)
     1. 04:22 AM - Re: Wig-Wag Makes Strange Buzz (Robert L. Nuckolls, III)
     2. 04:51 AM - Re: B&C  (Robert L. Nuckolls, III)
     3. 04:52 AM - Re: Wig-Wag Makes Strange Buzz (Robert L. Nuckolls, III)
     4. 05:16 AM - Re: Wig-Wag Makes Strange Buzz (Ken)
     5. 05:29 AM - Re: Wig-Wag Makes Strange Buzz (the rest of the story) (Robert L. Nuckolls, III)
     6. 06:18 AM - Re: B&C  (Bob Lee)
     7. 07:16 AM - Re: Duel LSI ignitions (No mags) (Mike)
     8. 07:16 AM - Re: Duel LSI ignitions (No mags) (Roger Bentlage)
     9. 07:25 AM - Re: Wig-Wag Makes Strange Buzz (Robert L. Nuckolls, III)
    10. 07:40 AM - Re: B&C  (Robert L. Nuckolls, III)
    11. 08:05 AM - Re: Homebrew AHRS? (6440 Auto Parts)
    12. 08:58 AM - Re: Flaked Regulator? (Bob Verwey)
    13. 09:08 AM - Fw: Homebrew AHRS? (Ed Anderson)
    14. 09:55 AM - Re: Flaked Regulator? (Ken)
    15. 10:34 AM - Re: D10-a check lists and POH (Ken Harrill)
    16. 11:00 AM - Z-19 questions (Bill Bradburry)
    17. 11:16 AM - Re: Homebrew AHRS? (Robert L. Nuckolls, III)
    18. 11:29 AM - Re: Fw: Homebrew AHRS? (Bill Boyd)
    19. 11:33 AM - Re: B&C  (Bob Lee)
    20. 12:20 PM - Re: Fw: Homebrew AHRS? (Charlie England)
    21. 12:35 PM - Fw: Fw: Homebrew AHRS? (Ed Anderson)
    22. 01:01 PM - Re: Homebrew AHRS? (Sean Stephens)
    23. 01:48 PM - Re: Homebrew AHRS? (Terry Watson)
    24. 01:58 PM - Re: Flaked Regulator? (Jim Baker)
    25. 02:34 PM - Re: Fw: Homebrew AHRS? (David M.)
    26. 02:52 PM - Re: Fw: Homebrew AHRS? (Ed Anderson)
    27. 03:06 PM - Re: 24V 12V grounds (flyadive@aol.com)
    28. 03:49 PM - Re: 24V 12V grounds (Matt Prather)
    29. 04:04 PM - Re: 24V 12V grounds (Ernest Christley)
    30. 04:11 PM - Re: 24V 12V grounds (Robert L. Nuckolls, III)
 
 
 


Message 0


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    Time: 01:02:14 AM PST US
    From: Matt Dralle <dralle@matronics.com>
    Subject: Please Make a Contribution to Support Your Lists...
    Dear Listers, Just a reminder that November is the Annual List Fund Raiser. Please make a Contribution today to support the continued operation and upgrade of these great List services!! Pick up a really nice free gift with your qualifying Contribution too! The Contribution Site is fast and easy: http://www.matronics.com/contribution Thank you! Matt Dralle Matronics Email List Administrator


    Message 1


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    Time: 04:22:53 AM PST US
    From: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
    Subject: Re: Wig-Wag Makes Strange Buzz
    At 10:54 PM 11/21/2006 -0500, you wrote: >Bob; > >When the notes say "won't operate" they don't necessarily mean sit there >dormant doing nothing. They mean won't give the desired or expected >result. This is exactly what is happening in your case. I don't know >positively for sure, but expect that this flasher's output is through a >double throw relay with both the normally open and normally closed >contacts also wired to a time delay on and time delay off circuit >operating the coil. The results you are getting are possibly explained by >the one light being connected to the NC contact therefore turning the lamp >"on". Connecting the other lamp to the NO output which is the "turn on >timer" circuit, also momentarily closes the relay turning on the lamp, but >instantaneously it turns off again because there is no load on the other >output, thus putting the timer into a "buzzer" mode where the action of >turning on the relay turns it off. With both loads connected the on-off >action of the timer operates correctly causing the relay contacts to >rhythmically transfer, making the two outputs alternately turn on for >roughly equal amounts of time. (poor explanation, I know, but hopefully >you get the idea) The "buzzer" action is so fast that the lamp only >appears to glow, or flicker, because the "on" time is so short. Your perceptions and analysis are correct. Well done. If I had designed the flasher, it would have been a 4-wire device and its operation would have been independent of which or how many load lamps were attached. This is an automotive flasher intended to replace the classic 3-wire, thermal devices used on vehicles for a very long time. When you don't have the 4th lead for a solid ground, the circuit depends on seeing a ground in through the OFF side lamp. Bob . . .


    Message 2


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    Time: 04:51:19 AM PST US
    From: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
    Subject: Re: B&C
    At 01:21 PM 11/21/2006 -0500, you wrote: > >I just tried to order an LRC3-14 linear voltage regulator from B&C. I >figured that I would go for the battery temperature option to give my >battery the best attention that I could. The guys at B&C said that you only >need the battery temperature option if you are somewhere like the north >pole. I don't get it, doesn't the battery need a different level of charge >from summer to winter? I don't understand why B&C is reluctant to sell the >battery temperature option on their LRC3-14 voltage regulater. Anybody >understand the physics of that recomendation? It's a matter of return on investment for the $time$ required to incorporate any particular feature. If you study the manuals for batteries, you'll find prescriptions for optimal battery performance based on their laboratory tests and the considered opinions of their staff. Not all manufacturer's have the same recommendations. This has sparked discussions here on the List about whether or not any particular brand or technology of battery is best served by setting a regulator at 14.1 or 14.3 volts, etc. However, the manner in which we use batteries is a far cry from the manner in which they are tested for "optimal" performance. Further, I've never seen a study by manufacturers or others that quantify the penalties of operating a battery in less-than optimal conditions. Would a 14.5 volt setting cause me to replace a battery one month too soon? I suspect that the data we'd like to see will never be forthcoming mostly because departures from optimized operating conditions in service are (1) of so little influence as to be practical considerations and/or (2) so much trouble to accomplish that return on investment is poor. I designed the temperature compensator probe for the LR series regulators to address a profound performance issue. One of our customers frequently traveled long distances at high cruising altitudes that cold-soaked his battery. After the third or forth fuel stop, his battery would not vigorously crank the engine. It was so cold that the nominal 14.2 volt set-point was not recharging the battery. The thrust of B&C's recommendations take this experience into consideration such that they do not recommend the temperature compensator unless you EXPECT or have EXPERIENCED battery failure-to- perform based on temperature effects. A very rare condition in the OBAM aircraft community. Further, any fussing one might choose to do over seasonally adjusting their bus voltage is problematic as to whether any increased battery performance or longevity will be perceived. Bob . . .


    Message 3


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    Time: 04:52:25 AM PST US
    From: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
    Subject: Wig-Wag Makes Strange Buzz
    At 11:23 AM 11/21/2006 -0600, you wrote: >The benefit of wig-wags, as well as alternating strobes, is that they >produce a sense of movement which is more readily detected by the eye than >a fixed position light, whether steady or flashing. > >Regards, >Greg Young Right on! Bob . . . --------------------------------------------------------- < What is so wonderful about scientific truth...is that > < the authority which determines whether there can be > < debate or not does not reside in some fraternity of > < scientists; nor is it divine. The authority rests > < with experiment. > < --Lawrence M. Krauss > ---------------------------------------------------------


    Message 4


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    Time: 05:16:47 AM PST US
    From: Ken <klehman@albedo.net>
    Subject: Re: Wig-Wag Makes Strange Buzz
    The 3 lead device provides immediate audio notification of a burned out light bulb when installed in a reasonably quiet vehicle. Some days I notice an amazing percentage of vehicles with one (or often several) dead bulbs and that is a definate contributor to accidents! Ken Robert L. Nuckolls, III wrote: > <nuckollsr@cox.net> > > At 10:54 PM 11/21/2006 -0500, you wrote: > >> Bob; >> >> When the notes say "won't operate" they don't necessarily mean sit >> there dormant doing nothing. They mean won't give the desired or >> expected result. This is exactly what is happening in your case. I >> don't know positively for sure, but expect that this flasher's output >> is through a double throw relay with both the normally open and >> normally closed contacts also wired to a time delay on and time delay >> off circuit operating the coil. The results you are getting are >> possibly explained by the one light being connected to the NC contact >> therefore turning the lamp "on". Connecting the other lamp to the NO >> output which is the "turn on timer" circuit, also momentarily closes >> the relay turning on the lamp, but instantaneously it turns off again >> because there is no load on the other output, thus putting the timer >> into a "buzzer" mode where the action of turning on the relay turns >> it off. With both loads connected the on-off action of the timer >> operates correctly causing the relay contacts to rhythmically >> transfer, making the two outputs alternately turn on for roughly >> equal amounts of time. (poor explanation, I know, but hopefully you >> get the idea) The "buzzer" action is so fast that the lamp only >> appears to glow, or flicker, because the "on" time is so short. > > > Your perceptions and analysis are correct. Well done. > If I had designed the flasher, it would have been a 4-wire > device and its operation would have been independent of > which or how many load lamps were attached. This is an > automotive flasher intended to replace the classic 3-wire, > thermal devices used on vehicles for a very long time. > When you don't have the 4th lead for a solid ground, the > circuit depends on seeing a ground in through the OFF > side lamp. > > Bob . . .


    Message 5


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    Time: 05:29:07 AM PST US
    From: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
    Subject: RE: Wig-Wag Makes Strange Buzz (the rest of the story)
    I didn't finish the thought in the paragraphs below - so here's the rest of the story: The principal of a pair alternately illuminated lights is the same . . . generate a perception of motion. Years ago when we started installing the incandescent Aeroflash beacons on Cessnas, there was a lot of objection to the flashing of panel lights when the SINGLE 12A bulb was cycled on and off. Since our flasher modules would handle two lamps, we tried on lamp on top of vertical fin and the other on the bottom of the fuselage. THE IDEA WAS THAT HAVING AT LEAST ONE LAMP LIT ALL THE TIME WOULD REDUCE THE BUS VOLTAGE PERTURBATIONS AND STOP THE IRRITATING 'BEAT' IN PANEL LIGHTING. THE FIX "WORKED". HOWEVER . . . Vertical separation was on the order of 10' so you had to be less than a mile away before the alternately flashing lights would be perceived to have vertical motion as opposed to looking like a single, always lit lamp. SO, INSTEAD OF TWO LAMPS TO PRESENT A CONSTANT LOAD TO THE BUS, WE WENT TO ONE LAMP AND A FAT RESISTOR IN PLACE OF THE SECOND LAMP. THE APPEARANCE OF 'FLASHING' AT DISTANCE WAS RESTORED AND FLICKERING IN THE PANEL LIGHTS WAS SURPRESSED. So it isn't just the flash but a combination of things most important of which is appearance of motion that makes the wig-wag system work well. Got to study these issues in detail back in my accident investigation and courtroom presentations days. Bob . . . -- -- incoming mail is certified Virus Free. Checked by AVG Anti-Virus. Bob . . . --------------------------------------------------------- < What is so wonderful about scientific truth...is that > < the authority which determines whether there can be > < debate or not does not reside in some fraternity of > < scientists; nor is it divine. The authority rests > < with experiment. > < --Lawrence M. Krauss > ---------------------------------------------------------


    Message 6


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    Time: 06:18:10 AM PST US
    From: "Bob Lee" <bob@flyboybob.com>
    Subject: B&C
    BobK wrote: << The thrust of B&C's recommendations take this experience into consideration such that they do not recommend the temperature compensator unless you EXPECT or have EXPERIENCED battery failure-to- perform based on temperature effects. A very rare condition in the OBAM aircraft community. Further, any fussing one might choose to do over seasonally adjusting their bus voltage is problematic as to whether any increased battery performance or longevity will be perceived. Bob . . . >> There are conditions other than "battery failure" that make the use of the temperature sensor a good idea. During winter time flying the battery will be cold-soaked at the time that it needs to do it's heaviest job, crank the engine. This puts the battery at an even lower state of charge. The most important use of the battery is to power the flight essential loads under alternator failure conditions. Since I have a composite aircraft I have decided to use a linear regulator. The B&C LRC3-14 already has the temperature sence capability built into it. So for the price of a couple of batteries I can add the sensor and use this included feature. Would it work ok without the sensor, sure, but I think it will give me an advantage when the battery is cold to get to full charge quicker. The proof will be in monitoring bus voltage vs temperature to see if anything changes. Thanks for the information Bob, even if I do go the opposite way you indicated! Regards, Bob Lee N52BL KR2 Suwanee, GA 91% done only 65% to go!


    Message 7


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    Time: 07:16:53 AM PST US
    From: "Mike" <mlas@cox.net>
    Subject: Duel LSI ignitions (No mags)
    Don, I have been running dual LSI on my IO-550 powered Lancair Legacy since Feb. 2006 and have 160 hours on it so far. I also wanted full night and IFR capabilities. I went with the Z-14, 12 volt system, 80amp primary alternator, and the 20 amp B&C alternator. The 80 amp main bus runs most everything and the 20 amp bus runs one ignition, backup EFIS, autopilot, landing gear indicators, and backup power for dual bus avionics such as the air data computer, primary EFIS gyro, Nav/Com and transponder. With everything running on the 20 amp bus I draw about 11 amps and can continue running the airplane in an IFR environment. I read many post about running lighting on the secondary bus. When you lose more then half of your power, the last thing you need are lights. My airplane is setup with 8 busses: Two Ignition Busses 1 left & right, (wired before the master contactor, so when the ignition switches are on the ignition system is powered regardless of master switch position.) Two direct battery busses 1 left & right(for courtesy items such as cargo light and plug-ins for a GPS or other devices not used in flight, main busses 1 left & right (all non-avionics systems), Two avionics busses 1 left and right (all avionics systems). The main busses have a tie contactor (normally always open/off) to provide additional starting power and power in the event of an alternator failure on one side. The avionics busses have a tie (normally always open/off) in the event of a main bus fault or avionics contactor failure. If I had to say what the most important aspect of my system is, I would say having the Ignition system on its own bus allowing it to get power when all other systems are shut down of fail. In my system you would have to loose both batteries (less than 5vdc nominal) to loose both ignition systems. To date the system has worked flawlessly. Mike Larkin Lancair Legacy TS-11 Iskra Kitfox IV A-319/320 -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com]On Behalf Of Don Owens Sent: Tuesday, November 21, 2006 12:21 PM Subject: AeroElectric-List: Duel LSI ignitions (No mags) <springcanyon@methow.com> Hi all, I would like some input on what would make others feel comfortable when powering duel electronic ignitions. I plan to have night and IFR capability in an RV-7. I have looked at Bob's schematics: Z-12 and Z-14. The Z-14 certainly covers all the bases, but I hate to hang an extra battery up front if it is not absolutely necessary. I am thinking that the Z-12 with the B&C 40 amp alternator up front and a B&C 20 amp alternator on the vacuum pump pad and a 17 amp/hr battery that would be redundancy enough. Am I living on the edge? Thanks for the input Don Owens Read this topic online here: http://forums.matronics.com/viewtopic.php?p=76132#76132 -- 10/16/2006 -- 10/16/2006


    Message 8


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    Time: 07:16:53 AM PST US
    Subject: Re: Duel LSI ignitions (No mags)
    From: "Roger Bentlage" <bentlage@sbcglobal.net>
    Don, I have a similar situation. Dual LSI, Garmin stack, dual BMA EFIS, AFS engine monitor, IO 360, all electric aircraft. I opted for two totally independent electrical systems but with the ability to tie them together. B&C 60 as primary, B&C20 on the vacuum pad. LSIs directly to the batteries through guarded toggle switches. Radios, EFIS, lights, etc split between the two systems. I have a CAD (.dxf or .fcw) drawing I would be glad to share if anyone is interested. Roger RV-7 nearing completion Read this topic online here: http://forums.matronics.com/viewtopic.php?p=76373#76373


    Message 9


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    Time: 07:25:33 AM PST US
    From: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
    Subject: Re: Wig-Wag Makes Strange Buzz
    At 08:18 AM 11/22/2006 -0500, you wrote: > >The 3 lead device provides immediate audio notification of a burned out >light bulb when installed in a reasonably quiet vehicle. Some days I >notice an amazing percentage of vehicles with one (or often several) dead >bulbs and that is a definate contributor to accidents! >Ken Very good! Only a dedicated OBAMer could truly make a silk purse from a sows ear! I hadn't thought of that. I'll add a note to that effect in the Wig-Wag wiring diagrams. Thanks! Bob . . .


    Message 10


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    Time: 07:40:01 AM PST US
    From: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
    Subject: B&C
    At 09:16 AM 11/22/2006 -0500, you wrote: > >BobK wrote: > ><< > > The thrust of B&C's recommendations take this > experience into consideration such that they do not > recommend the temperature compensator unless you > EXPECT or have EXPERIENCED battery failure-to- > perform based on temperature effects. A very rare > condition in the OBAM aircraft community. > > Further, any fussing one might choose to do over > seasonally adjusting their bus voltage is problematic > as to whether any increased battery performance or > longevity will be perceived. > > Bob . . . > >> > > >There are conditions other than "battery failure" that make the use of the >temperature sensor a good idea. During winter time flying the battery will >be cold-soaked at the time that it needs to do it's heaviest job, crank the >engine. This puts the battery at an even lower state of charge. The most >important use of the battery is to power the flight essential loads under >alternator failure conditions. Since I have a composite aircraft I have >decided to use a linear regulator. The B&C LRC3-14 already has the >temperature sence capability built into it. So for the price of a couple of >batteries I can add the sensor and use this included feature. > >Would it work ok without the sensor, sure, but I think it will give me an >advantage when the battery is cold to get to full charge quicker. The proof >will be in monitoring bus voltage vs temperature to see if anything changes. > >Thanks for the information Bob, even if I do go the opposite way you >indicated! How is it opposite? You have stated a perceived value in temperature compensating your alternator output based on battery temperature. You've correctly cited the mechanisms by which some advantages may be gained when temperature compensation is added. What's missing is quantification of your assertions. "Get to full charge quicker" is un-quantified. I would suggest it's useful to know the return on investment for "the price of a couple of batteries". Keep in mind that aviation has stumbled along with lead-acid batteries for nearly 100 years. I've flown in the winter and had to wrestle with battery limitations for getting engines started like tens of thousands of pilots before me. Recall further that if you've just beat the crap out of a battery getting the engine started that internal losses in the battery are high and it will warm up considerably by the time you got the engine started and it's ready to accept a charge . . . I'm not trying to discourage you from making the jump to temperature compensated charging. I'll suggest that having a second alternator on the vacuum pump pad is a 100% sure bet for quantifying your ability to operate the airplane with a main alternator crapped while adding temperature compensation only begs more questions than it answers. Questions that can only be answered by extensive experimentation and study of results. Bob . . .


    Message 11


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    Time: 08:05:34 AM PST US
    From: "6440 Auto Parts" <sales@6440autoparts.com>
    Subject: Re: Homebrew AHRS?
    I personally don't see the sense in spending $2000-$5000 building your own AHRS according to that website when a Dynon or GRT etc. can be bought ready to go. And they are tried and true. Unless of course one wanted to market one or just does'nt have anything better to do. But of course time permitting one could be built cheap well........ Randy ----- Original Message ----- From: "Ed Anderson" <eanderson@carolina.rr.com> Sent: Tuesday, November 21, 2006 7:39 PM Subject: Re: AeroElectric-List: Homebrew AHRS? > <eanderson@carolina.rr.com> > > Hi Sean, > > Try out this URL http://www.aerospectra.com/efis/svis.htm > > Dr Jim Hauser has a book worth getting on the basics as well as the > components to get started. > > Ed > > Ed Anderson > Rv-6A N494BW Rotary Powered > Matthews, NC > eanderson@carolina.rr.com > http://members.cox.net/rogersda/rotary/configs.htm#N494BW > http://www.dmack.net/mazda/index.html > ----- Original Message ----- > From: "Sean Stephens" <sean@stephensville.com> > To: <aeroelectric-list@matronics.com> > Sent: Tuesday, November 21, 2006 1:04 PM > Subject: AeroElectric-List: Homebrew AHRS? > > >> <sean@stephensville.com> >> >> I've been scouring Google trying to find literature, schematics, etc. on >> building an AHRS/ADAHRS. I've been unable to find anything that would >> get me jump-started on a homebrew project. >> >> If anyone has links that would help I'd appreciate it. >> >> -Sean >> >> >> >> > > >


    Message 12


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    Time: 08:58:55 AM PST US
    From: "Bob Verwey" <bonanza@vodamail.co.za>
    Subject: Flaked Regulator?
    Micheal, I have the same problem in my Bonanza, even with no load. At startup and low revs, needle is steady at charge 20-30 amps. Within 30 seconds the "retriever syndrome" starts. O/h the alternator and changed the regulator. No difference. Also can hear the wig/wag in the headsets. Quite irritating. I notice the voltage fluctuation on my "gear up" light. Bob Verwey A35 Bonanza _____ From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Deems Herring Sent: 21 Nov 2006 06:33 PM Subject: RE: AeroElectric-List: Flaked Regulator? Does the needle go in time with the flashing beacon? The beacon will draw about 10 - 11 amps and will cause the needle to fluctuate. The power supply is usually 2 sided so it can run a top and bottom beacon. Some planes with 1 beacon put a resistor on the other side of the power supply as a load to stop the fluctuation. Deems _____ From: cfi@conwaycorp.net Subject: AeroElectric-List: Flaked Regulator? Hello Bob and All. I noticed in a friend's Cessna 152 that the ammeter needle wags back and forth like a golden retriever's tail at a steak dinner, except at half and not full deflection. He said it has always done that. I turned the dome light on and noticed it dims and brightens at the same frequency as the needle wag. I'm assuming the voltage regulator has flaked out, but we all know what assumptions do. How would you suggest troubleshooting this? Is this a real problem or a just a nuisance? The limited avionics are all FAA TSO'd, so I'm assuming they have adequate spike/surge protection built in, but I'm not so sure a constant barrage of surge/spikes was considered in the design. Please share your thoughts. Michael H. _____ Express yourself with gadgets on Windows Live Spaces Try <http://discoverspaces.live.com?source=hmtag1&loc=us> it!


    Message 13


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    Time: 09:08:52 AM PST US
    From: "Ed Anderson" <eanderson@carolina.rr.com>
    Subject: Homebrew AHRS?
    > Your correct, Randy, assuming that the only objective/goal is to have an > AHRS in your panel. > > But, some simply want to continue the "educational" goal of Amateur build > aircraft by expanding into other associated areas. I designed and built > my own EFI Fuel Monitoring System which uses no fuel flow transducer - > yes, the parts were certainly cheaper than a purchased one - but, if I > included even a modest value for my time - then the commercial one would > have been cheaper {:>). But, the goal was not just to build my own, but > to learn to design,build and program using microchips. > > I've just completed a design and prototype for an AOA indicator - again, > not because one could not be purchased at a reasonable price - but simply > because I enjoy learning new things and building. > > Different strokes for different folks. > > Ed > Ed Anderson > Rv-6A N494BW Rotary Powered > Matthews, NC > eanderson@carolina.rr.com > http://members.cox.net/rogersda/rotary/configs.htm#N494BW > http://www.dmack.net/mazda/index.html > > ----- Original Message ----- > From: "6440 Auto Parts" <sales@6440autoparts.com> > To: <aeroelectric-list@matronics.com> > Sent: Wednesday, November 22, 2006 11:03 AM > Subject: Re: AeroElectric-List: Homebrew AHRS? > > >> <sales@6440autoparts.com> >> >> I personally don't see the sense in spending $2000-$5000 >> building your own AHRS according to that website when a Dynon or GRT etc. >> can be bought ready to go. And they are tried and true. >> Unless of course one wanted to market one or just does'nt have >> anything better to do. >> But of course time permitting one could be built cheap >> well........ >> >> Randy >> >> >> >> ----- Original Message ----- >> From: "Ed Anderson" <eanderson@carolina.rr.com> >> To: <aeroelectric-list@matronics.com> >> Sent: Tuesday, November 21, 2006 7:39 PM >> Subject: Re: AeroElectric-List: Homebrew AHRS? >> >> >>> <eanderson@carolina.rr.com> >>> >>> Hi Sean, >>> >>> Try out this URL http://www.aerospectra.com/efis/svis.htm >>> >>> Dr Jim Hauser has a book worth getting on the basics as well as the >>> components to get started. >>> >>> Ed >>> >>> Ed Anderson >>> Rv-6A N494BW Rotary Powered >>> Matthews, NC >>> eanderson@carolina.rr.com >>> http://members.cox.net/rogersda/rotary/configs.htm#N494BW >>> http://www.dmack.net/mazda/index.html >>> ----- Original Message ----- >>> From: "Sean Stephens" <sean@stephensville.com> >>> To: <aeroelectric-list@matronics.com> >>> Sent: Tuesday, November 21, 2006 1:04 PM >>> Subject: AeroElectric-List: Homebrew AHRS? >>> >>> >>>> <sean@stephensville.com> >>>> >>>> I've been scouring Google trying to find literature, schematics, etc. >>>> on building an AHRS/ADAHRS. I've been unable to find anything that >>>> would get me jump-started on a homebrew project. >>>> >>>> If anyone has links that would help I'd appreciate it. >>>> >>>> -Sean >>>> >>>> >>>> >>>> >>> >>> >>> >>> >>> >>> >>> >> >> >> >> >> >> >


    Message 14


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    Time: 09:55:32 AM PST US
    From: Ken <klehman@albedo.net>
    Subject: Re: Flaked Regulator?
    With the Mechanical flasher, two identical lights, and ground wires running from the lights to the forest of tabs (instead of using the airframe ground), I have no discernable noise in the headset. FWIW I believe that grounding method is also the way to get rid of the slight headset whine from my aeroflash strobes although it is a bit of work to isolate the power supply from my metal wingspars. I can only hear the whine on the ground so it is low priority. Ken Bob Verwey wrote: > Micheal, > I have the same problem in my Bonanza, even with no load. At startup > and low revs, needle is steady at charge 20-30 amps. Within 30 seconds > the "retriever syndrome" starts. O/h the alternator and changed the > regulator. No difference. Also can hear the wig/wag in the headsets. > Quite irritating. I notice the voltage fluctuation on my "gear up" light. > Bob Verwey > A35 Bonanza > > ------------------------------------------------------------------------ > From: owner-aeroelectric-list-server@matronics.com > [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of > Deems Herring > Sent: 21 Nov 2006 06:33 PM > To: aeroelectric-list@matronics.com > Subject: RE: AeroElectric-List: Flaked Regulator? > > > Does the needle go in time with the flashing beacon? The beacon will > draw about 10 - 11 amps and will cause the needle to fluctuate. The > power supply is usually 2 sided so it can run a top and bottom beacon. > Some planes with 1 beacon put a resistor on the other side of the > power supply as a load to stop the fluctuation. > > Deems > > > ------------------------------------------------------------------------ > From: cfi@conwaycorp.net > To: aeroelectric-list@matronics.com > Subject: AeroElectric-List: Flaked Regulator? > Date: Tue, 21 Nov 2006 08:17:19 -0600 > > Hello Bob and All. I noticed in a friends Cessna 152 that the > ammeter needle wags back and forth like a golden retrievers tail > at a steak dinner, except at half and not full deflection. He said > it has always done that. I turned the dome light on and noticed it > dims and brightens at the same frequency as the needle wag. Im > assuming the voltage regulator has flaked out, but we all know > what assumptions do. How would you suggest troubleshooting this? > Is this a real problem or a just a nuisance? The limited avionics > are all FAA TSOd, so Im assuming they have adequate spike/surge > protection built in, but Im not so sure a constant barrage of > surge/spikes was considered in the design. Please share your thoughts. >


    Message 15


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    Time: 10:34:58 AM PST US
    Subject: Re: D10-a check lists and POH
    From: "Ken Harrill" <kharrill@osa.state.sc.us>
    Jim, I have one for my RV-6, 180 hp, C/S that I will be glad to send you. I can't attach it to this message because it does not have an acceptable file extension. Ken Harrill ken.harrill@columbia.sc -------- Ken Harrill RV-6 Columiba, SC Read this topic online here: http://forums.matronics.com/viewtopic.php?p=76415#76415


    Message 16


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    Time: 11:00:57 AM PST US
    From: Bill Bradburry <bbradburry@allvantage.com>
    Subject: Z-19 questions
    Bob, et al, I am installing a fuel injected Mazda rotary engine and trying to follow the Z-19 guidelines for dual battery, single alternator. Looking at the engine primary and secondary circuit, I need to install a primary and secondary fuel pump, plus I want to power the coils and the injectors off of the battery buss. How should I do this? I suppose I could take the fuel pump diode output and switch it to either of the two fuel pumps??? What about the coils and injectors? Should I set up similar circuits for them, or is there a better way to reduce parts??? I would appreciate any guidance you guys could give me. Thanks and Happy Thanksgiving! Bill B


    Message 17


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    Time: 11:16:35 AM PST US
    From: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
    Subject: Re: Homebrew AHRS?
    At 10:03 AM 11/22/2006 -0600, you wrote: ><sales@6440autoparts.com> > > I personally don't see the sense in spending $2000-$5000 > building your own AHRS according to that website when a Dynon or GRT etc. > can be bought ready to go. And they are tried and true. > Unless of course one wanted to market one or just does'nt have > anything better to do. > But of course time permitting one could be built cheap well........ Depends on the goal. I'm presently trying to sell some MBA types on the value of IR&D with an emphasis on the "I". Should you wish to understand and make utility of the ingredients needed to accomplish a task, you need to start with the simple-ideas. The task is to explore how they perform and the elegant ways they may be assembled into useful products. If someone expresses a desire to "build" something, it's not uncommon for folk to counsel against the activity for a variety of reasons not the least of which is a perceived re-invention of some wheel. Randy has suggested that he might build one "cheap". I CAN advise that for the majority of cases, tasks of this nature may be emulated but unless your time has zero value, it's never cheap. While the hardware IS readily available and inexpensive, an AHRS system designed around rate sensors is exceedingly software intensive. Launching a new project of this type without the support of a cadre' of smart people (knowledgeable and experienced) is risky . . . especially if you plan to poke your airplane into clouds. The task is much more than buying some parts and wiring them together. You need a working knowledge of crafting flight stabilization software. You also need a means for testing it without risking life, limb or airplane. We used to do a lot of this work at RAC Missiles and had hardware-in-the-loop simulation for testing. So before we can advise Randy well, we need to know what his plan is. The starting point is today and the end point is (????). What is it you wish to achieve Randy? Be aware too that the successful ventures of this type are never "cheap." Bob . . .


    Message 18


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    Time: 11:29:28 AM PST US
    From: "Bill Boyd" <sportav8r@gmail.com>
    Subject: Re: Homebrew AHRS?
    Okay, Ed. Want to tell us how you did it without a transducer? Minds that need examining want to know... -Stormy On 11/22/06, Ed Anderson <eanderson@carolina.rr.com> wrote: > > > > Your correct, Randy, assuming that the only objective/goal is to have an > > AHRS in your panel. > > > > But, some simply want to continue the "educational" goal of Amateur build > > aircraft by expanding into other associated areas. I designed and built > > my own EFI Fuel Monitoring System which uses no fuel flow transducer - > > yes, the parts were certainly cheaper than a purchased one - but, if I > > included even a modest value for my time - then the commercial one would > > have been cheaper {:>). But, the goal was not just to build my own, but > > to learn to design,build and program using microchips. > > > > I've just completed a design and prototype for an AOA indicator - again, > > not because one could not be purchased at a reasonable price - but simply > > because I enjoy learning new things and building. > > > > Different strokes for different folks. > > > > Ed > > Ed Anderson > > Rv-6A N494BW Rotary Powered > > Matthews, NC > > eanderson@carolina.rr.com > > http://members.cox.net/rogersda/rotary/configs.htm#N494BW > > http://www.dmack.net/mazda/index.html > > > > ----- Original Message ----- > > From: "6440 Auto Parts" <sales@6440autoparts.com> > > To: <aeroelectric-list@matronics.com> > > Sent: Wednesday, November 22, 2006 11:03 AM > > Subject: Re: AeroElectric-List: Homebrew AHRS? > > > > > >> <sales@6440autoparts.com> > >> > >> I personally don't see the sense in spending $2000-$5000 > >> building your own AHRS according to that website when a Dynon or GRT etc. > >> can be bought ready to go. And they are tried and true. > >> Unless of course one wanted to market one or just does'nt have > >> anything better to do. > >> But of course time permitting one could be built cheap > >> well........ > >> > >> Randy > >> > >> > >> > >> ----- Original Message ----- > >> From: "Ed Anderson" <eanderson@carolina.rr.com> > >> To: <aeroelectric-list@matronics.com> > >> Sent: Tuesday, November 21, 2006 7:39 PM > >> Subject: Re: AeroElectric-List: Homebrew AHRS? > >> > >> > >>> <eanderson@carolina.rr.com> > >>> > >>> Hi Sean, > >>> > >>> Try out this URL http://www.aerospectra.com/efis/svis.htm > >>> > >>> Dr Jim Hauser has a book worth getting on the basics as well as the > >>> components to get started. > >>> > >>> Ed > >>> > >>> Ed Anderson > >>> Rv-6A N494BW Rotary Powered > >>> Matthews, NC > >>> eanderson@carolina.rr.com > >>> http://members.cox.net/rogersda/rotary/configs.htm#N494BW > >>> http://www.dmack.net/mazda/index.html > >>> ----- Original Message ----- > >>> From: "Sean Stephens" <sean@stephensville.com> > >>> To: <aeroelectric-list@matronics.com> > >>> Sent: Tuesday, November 21, 2006 1:04 PM > >>> Subject: AeroElectric-List: Homebrew AHRS? > >>> > >>> > >>>> <sean@stephensville.com> > >>>> > >>>> I've been scouring Google trying to find literature, schematics, etc. > >>>> on building an AHRS/ADAHRS. I've been unable to find anything that > >>>> would get me jump-started on a homebrew project. > >>>> > >>>> If anyone has links that would help I'd appreciate it. > >>>> > >>>> -Sean > >>>> > >>>> > >>>> > >>>> > >>> > >>> > >>> > >>> > >>> > >>> > >>> > >> > >> > >> > >> > >> > >> > > > >


    Message 19


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    Time: 11:33:56 AM PST US
    From: "Bob Lee" <bob@flyboybob.com>
    Subject: B&C
    BobK wrote: I'm not trying to discourage you from making the jump to temperature compensated charging. Good, it sounded to me you were making a case supporting B&C against this option I'll suggest that having a second alternator on the vacuum pump pad is a 100% sure bet for quantifying your ability to operate the airplane with a main alternator crapped Agreed, I've got an aux alternator installed while adding temperature compensation only begs more questions than it answers. Questions that can only be answered by extensive experimentation and study of results. Now there's the catch-22, if I don't install the temp sensor we will never have the data to know if I should. As it turns out it's a gut decision because you can't have data ahead to know what is the best thing to do. I'm looking at this as a chance to improve the recovery time of the battery to full charge. I really don't care about long term battery effects. Battery only operation is the last resort for my electrically dependant engine if some failure or failures prevent alternator operation for both the primary and aux alternators. In addition there is the time between the detection of low voltage and implementation of the low voltage check list. The better shape the battery is in the less stress there is during this phase of emergency flight operation. I don't ever want to get to step 6 of the low voltage check list: (Step 6: If low voltage still exists after turning on the aux alternator LAND NOW)! If I do get there I want every advantage stacked in my favor to streatch the battery operation for that flight. According to BobK's law #1, Things WILL break. My adaptation of that law is that: Things WILL break in ways you haven't anticipated. That's why I want to have a better battery even though I have two alternators. I figure battery state with temp sense will be at worst the same and at best better than with out temp sense. So I'll do without one $100 hamburger and add the temp sensor. Data to follow! Bob . . . Me too!


    Message 20


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    Time: 12:20:06 PM PST US
    From: Charlie England <ceengland@bellsouth.net>
    Subject: Re: Homebrew AHRS?
    You're out of luck, Bill. It takes a fuel delivery system designed post stone age. Charlie (reluctantly contemplating a stone age engine to save build time) Bill Boyd wrote: > <sportav8r@gmail.com> > > Okay, Ed. Want to tell us how you did it without a transducer? > > Minds that need examining want to know... > > -Stormy > > On 11/22/06, Ed Anderson <eanderson@carolina.rr.com> wrote: > >> <eanderson@carolina.rr.com> >> >> >> >> >> > Your correct, Randy, assuming that the only objective/goal is to >> have an >> > AHRS in your panel. >> > >> > But, some simply want to continue the "educational" goal of Amateur >> build >> > aircraft by expanding into other associated areas. I designed and >> built >> > my own EFI Fuel Monitoring System which uses no fuel flow transducer - >> > yes, the parts were certainly cheaper than a purchased one - but, if I >> > included even a modest value for my time - then the commercial one >> would >> > have been cheaper {:>). But, the goal was not just to build my >> own, but >> > to learn to design,build and program using microchips. >> > >> > I've just completed a design and prototype for an AOA indicator - >> again, >> > not because one could not be purchased at a reasonable price - but >> simply >> > because I enjoy learning new things and building. >> > >> > Different strokes for different folks. >> > >> > Ed >> > Ed Anderson >> > Rv-6A N494BW Rotary Powered >> > Matthews, NC >> > eanderson@carolina.rr.com >> > http://members.cox.net/rogersda/rotary/configs.htm#N494BW >> > http://www.dmack.net/mazda/index.html >


    Message 21


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    Time: 12:35:23 PM PST US
    From: "Ed Anderson" <eanderson@carolina.rr.com>
    Subject: Homebrew AHRS?
    > Ok Stormy, you asked for it {:>). > > The "secret" is that my fuel system is Electronic Fuel Injection - The > short of it is - I measure the pulse width of the signal sent to the fuel > injectors. Skip the rest of the explanation which follows if that is > sufficient enough answer {:>). > > Knowing the flow rate of the injectors and the duration of each revolution > of the engine in which they are "turned on". This is used to form a ratio > of Injector-On_time/Period-of-revolution which is multiplied by the total > fuel flow capacity of the 4 injectors which gives the instantaneous flow > rate. Then I (rather the chip) calculates the instantaneous rate of flow > (adjusts the value for a 1 hour period) and displays it as "Gallons/Hour" > fuel burn. > > To totalize the amount of fuel use, I set a variable with a value of time > (microseconds) that equals 1/100 of a gallon (you could set it any > quantity). When the "on-time" of the injectors has equaled that amount of > time the Fuel totalizer increments by .01 gallon. and the "on-time" resets > to zero waiting for the injector-on duration to again build up to that > amount of time that equals 0.01 gallon again which then ticks over the > display to 0.02 gallons, etc. > > These values are stored in memory so when you shut down, when you restart > the engine, it picks up where it left off. Pilot set "Switch tank" and > "low fuel" alarms are incorporated as well as an Air/Fuel indictor for > mixture control. Fuel used, fuel remaining, time remaining at current burn > rate, RPM and calculated HP (just because the info was there to do it) are > also calculated and displayed on user selectable screens. It all fits in > a 2 1/4" instrument hole. > > So the only thing the unit needs is a single wire to one of the Fuel > injectors to get the pulse data (also needs one wire to the O2 sensor, if > using the Air/Fuel indication function) , this saves the $200 or so for a > fuel flow transducer. But, of course, it only works for electronic fuel > injectors. Another nice feature is you don't need to even consider the > unused fuel returned to the tank (some systems require two transducers to > handle this ) because this unit only measure fuel actually injected and > consumed and therefore doesn't worry about the fuel flowing in the lines > or being diverted back to the tank. > > The parts cost considerably less than the fuel transducer- but, the amount > of time it took me to learn to design with and program these microchips - > would have amounted to thousands of dollars even at the minimum wage rate > {:>) > > Now, aren't you sorry you asked {:>)? > > Ed > Ed Anderson > Rv-6A N494BW Rotary Powered > Matthews, NC > eanderson@carolina.rr.com > http://members.cox.net/rogersda/rotary/configs.htm#N494BW > http://www.dmack.net/mazda/index.html > > > ----- Original Message ----- > From: "Bill Boyd" <sportav8r@gmail.com> > To: <aeroelectric-list@matronics.com> > Sent: Wednesday, November 22, 2006 2:28 PM > Subject: Re: Fw: AeroElectric-List: Homebrew AHRS? > > >> <sportav8r@gmail.com> >> >> Okay, Ed. Want to tell us how you did it without a transducer? >> >> Minds that need examining want to know... >> >> -Stormy >> >> On 11/22/06, Ed Anderson <eanderson@carolina.rr.com> wrote: >>> <eanderson@carolina.rr.com> >>> >>> >>> >>> >>> > Your correct, Randy, assuming that the only objective/goal is to have >>> > an >>> > AHRS in your panel. >>> > >>> > But, some simply want to continue the "educational" goal of Amateur >>> > build >>> > aircraft by expanding into other associated areas. I designed and >>> > built >>> > my own EFI Fuel Monitoring System which uses no fuel flow transducer - >>> > yes, the parts were certainly cheaper than a purchased one - but, if I >>> > included even a modest value for my time - then the commercial one >>> > would >>> > have been cheaper {:>). But, the goal was not just to build my own, >>> > but >>> > to learn to design,build and program using microchips. >>> > >>> > I've just completed a design and prototype for an AOA indicator - >>> > again, >>> > not because one could not be purchased at a reasonable price - but >>> > simply >>> > because I enjoy learning new things and building. >>> > >>> > Different strokes for different folks. >>> > >>> > Ed >>> > Ed Anderson >>> > Rv-6A N494BW Rotary Powered >>> > Matthews, NC >>> > eanderson@carolina.rr.com >>> > http://members.cox.net/rogersda/rotary/configs.htm#N494BW >>> > http://www.dmack.net/mazda/index.html >>> > >>> > ----- Original Message ----- >>> > From: "6440 Auto Parts" <sales@6440autoparts.com> >>> > To: <aeroelectric-list@matronics.com> >>> > Sent: Wednesday, November 22, 2006 11:03 AM >>> > Subject: Re: AeroElectric-List: Homebrew AHRS? >>> > >>> > >>> >> <sales@6440autoparts.com> >>> >> >>> >> I personally don't see the sense in spending $2000-$5000 >>> >> building your own AHRS according to that website when a Dynon or GRT >>> >> etc. >>> >> can be bought ready to go. And they are tried and true. >>> >> Unless of course one wanted to market one or just does'nt >>> >> have >>> >> anything better to do. >>> >> But of course time permitting one could be built cheap >>> >> well........ >>> >> >>> >> Randy >>> >> >>> >> >>> >> >>> >> ----- Original Message ----- >>> >> From: "Ed Anderson" <eanderson@carolina.rr.com> >>> >> To: <aeroelectric-list@matronics.com> >>> >> Sent: Tuesday, November 21, 2006 7:39 PM >>> >> Subject: Re: AeroElectric-List: Homebrew AHRS? >>> >> >>> >> >>> >>> <eanderson@carolina.rr.com> >>> >>> >>> >>> Hi Sean, >>> >>> >>> >>> Try out this URL http://www.aerospectra.com/efis/svis.htm >>> >>> >>> >>> Dr Jim Hauser has a book worth getting on the basics as well as the >>> >>> components to get started. >>> >>> >>> >>> Ed >>> >>> >>> >>> Ed Anderson >>> >>> Rv-6A N494BW Rotary Powered >>> >>> Matthews, NC >>> >>> eanderson@carolina.rr.com >>> >>> http://members.cox.net/rogersda/rotary/configs.htm#N494BW >>> >>> http://www.dmack.net/mazda/index.html >>> >>> ----- Original Message ----- >>> >>> From: "Sean Stephens" <sean@stephensville.com> >>> >>> To: <aeroelectric-list@matronics.com> >>> >>> Sent: Tuesday, November 21, 2006 1:04 PM >>> >>> Subject: AeroElectric-List: Homebrew AHRS? >>> >>> >>> >>> >>> >>>> <sean@stephensville.com> >>> >>>> >>> >>>> I've been scouring Google trying to find literature, schematics, >>> >>>> etc. >>> >>>> on building an AHRS/ADAHRS. I've been unable to find anything that >>> >>>> would get me jump-started on a homebrew project. >>> >>>> >>> >>>> If anyone has links that would help I'd appreciate it. >>> >>>> >>> >>>> -Sean >>> >>>> >>> >>>> >>> >>>> >>> >>>> >>> >>> >>> >>> >>> >>> >>> >>> >>> >>> >>> >>> >>> >>> >>> >> >>> >> >>> >> >>> >> >>> >> >>> >> >>> > >>> >>> >>> >>> >>> >>> >>> >> >> >> >> >


    Message 22


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    Time: 01:01:27 PM PST US
    From: Sean Stephens <sean@stephensville.com>
    Subject: Re: Homebrew AHRS?
    Sorry to stir up a debate. This is purely for an educational experience on my part. I am in the middle of down time from building the airframe due to a relocation, so merely wanted to do some "experimenting" just to feed my brain. I was just looking for some literature and maybe a less $$ option than buying a commercial grade ADAHRS such as the xbow NAV420. Thanks all, -Sean (RV-10 40303 buildus interuptus) Bill Boyd wrote: > <sportav8r@gmail.com> > > Okay, Ed. Want to tell us how you did it without a transducer? > > Minds that need examining want to know... > > -Stormy > > On 11/22/06, Ed Anderson <eanderson@carolina.rr.com> wrote: >> <eanderson@carolina.rr.com> >> >> >> >> >> > Your correct, Randy, assuming that the only objective/goal is to >> have an >> > AHRS in your panel. >> > >> > But, some simply want to continue the "educational" goal of Amateur >> build >> > aircraft by expanding into other associated areas. I designed and >> built >> > my own EFI Fuel Monitoring System which uses no fuel flow transducer - >> > yes, the parts were certainly cheaper than a purchased one - but, if I >> > included even a modest value for my time - then the commercial one >> would >> > have been cheaper {:>). But, the goal was not just to build my >> own, but >> > to learn to design,build and program using microchips. >> > >> > I've just completed a design and prototype for an AOA indicator - >> again, >> > not because one could not be purchased at a reasonable price - but >> simply >> > because I enjoy learning new things and building. >> > >> > Different strokes for different folks. >> > >> > Ed >> > Ed Anderson >> > Rv-6A N494BW Rotary Powered >> > Matthews, NC >> > eanderson@carolina.rr.com >> > http://members.cox.net/rogersda/rotary/configs.htm#N494BW >> > http://www.dmack.net/mazda/index.html >> > >> > ----- Original Message ----- >> > From: "6440 Auto Parts" <sales@6440autoparts.com> >> > To: <aeroelectric-list@matronics.com> >> > Sent: Wednesday, November 22, 2006 11:03 AM >> > Subject: Re: AeroElectric-List: Homebrew AHRS? >> > >> > >> >> <sales@6440autoparts.com> >> >> >> >> I personally don't see the sense in spending $2000-$5000 >> >> building your own AHRS according to that website when a Dynon or >> GRT etc. >> >> can be bought ready to go. And they are tried and true. >> >> Unless of course one wanted to market one or just >> does'nt have >> >> anything better to do. >> >> But of course time permitting one could be built cheap >> >> well........ >> >> >> >> Randy >> >> >> >> >> >> >> >> ----- Original Message ----- >> >> From: "Ed Anderson" <eanderson@carolina.rr.com> >> >> To: <aeroelectric-list@matronics.com> >> >> Sent: Tuesday, November 21, 2006 7:39 PM >> >> Subject: Re: AeroElectric-List: Homebrew AHRS? >> >> >> >> >> >>> <eanderson@carolina.rr.com> >> >>> >> >>> Hi Sean, >> >>> >> >>> Try out this URL http://www.aerospectra.com/efis/svis.htm >> >>> >> >>> Dr Jim Hauser has a book worth getting on the basics as well as the >> >>> components to get started. >> >>> >> >>> Ed >> >>> >> >>> Ed Anderson >> >>> Rv-6A N494BW Rotary Powered >> >>> Matthews, NC >> >>> eanderson@carolina.rr.com >> >>> http://members.cox.net/rogersda/rotary/configs.htm#N494BW >> >>> http://www.dmack.net/mazda/index.html >> >>> ----- Original Message ----- >> >>> From: "Sean Stephens" <sean@stephensville.com> >> >>> To: <aeroelectric-list@matronics.com> >> >>> Sent: Tuesday, November 21, 2006 1:04 PM >> >>> Subject: AeroElectric-List: Homebrew AHRS? >> >>> >> >>> >> >>>> <sean@stephensville.com> >> >>>> >> >>>> I've been scouring Google trying to find literature, schematics, >> etc. >> >>>> on building an AHRS/ADAHRS. I've been unable to find anything that >> >>>> would get me jump-started on a homebrew project. >> >>>> >> >>>> If anyone has links that would help I'd appreciate it. >> >>>> >> >>>> -Sean


    Message 23


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    Time: 01:48:50 PM PST US
    From: "Terry Watson" <terry@tcwatson.com>
    Subject: Homebrew AHRS?
    Sean, There used to be an experimental avionics list somewhere. You might check the archives on Matt's Matronics Avionics list and see if there is still any discussion of what you are interested in, or maybe a reference to a list that does have it. Terry This is purely for an educational experience on my part. I am in the middle of down time from building the airframe due to a relocation, so merely wanted to do some "experimenting" just to feed my brain. I was just looking for some literature and maybe a less $$ option than buying a commercial grade ADAHRS such as the xbow NAV420. Thanks all, -Sean (RV-10 40303 buildus interuptus)


    Message 24


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    Time: 01:58:00 PM PST US
    From: "Jim Baker" <jlbaker@msbit.net>
    Subject: Flaked Regulator?
    X-mailer: Pegasus Mail for Windows (4.41) > I have the same problem in my Bonanza, even with no load. At startup and low revs, needle is > steady at charge 20-30 amps. Within 30 seconds the "retriever syndrome" starts. O/h the > alternator and changed the regulator. No difference. Also can hear the wig/wag in the headsets. > Quite irritating. I notice the voltage fluctuation on my "gear up" light. Go to the Zeftronics site. Read through the literature and troubleshooting tips. Almost guaranteed that high resistance in the field circuit is biting your butt. Throwing an ALT and REG at the problem wasn't the way do fix it..... Jim Baker 580.788.2779 '71 SV, 492TC Elmore City, OK


    Message 25


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    Time: 02:34:56 PM PST US
    From: "David M." <ainut@hiwaay.net>
    Subject: Re: Homebrew AHRS?
    Great things are being done now with MEMS, and at just a few dollars per function. David M. Ed Anderson wrote: > <eanderson@carolina.rr.com> > > >> Your correct, Randy, assuming that the only objective/goal is to >> have an AHRS in your panel. >> >> But, some simply want to continue the "educational" goal of Amateur >> build aircraft by expanding into other associated areas. I designed >> and built my own EFI Fuel Monitoring System which uses no fuel flow >> transducer - yes, the parts were certainly cheaper than a purchased >> one - but, if I included even a modest value for my time - then the >> commercial one would have been cheaper {:>). But, the goal was not >> just to build my own, but to learn to design,build and program using >> microchips. >> >> I've just completed a design and prototype for an AOA indicator - >> again, not because one could not be purchased at a reasonable price - >> but simply because I enjoy learning new things and building. >> >> Different strokes for different folks. >> >> Ed >> Ed Anderson >> Rv-6A N494BW Rotary Powered >> Matthews, NC >> eanderson@carolina.rr.com >> http://members.cox.net/rogersda/rotary/configs.htm#N494BW >> http://www.dmack.net/mazda/index.html >> >> ----- Original Message ----- From: "6440 Auto Parts" >> <sales@6440autoparts.com> >> To: <aeroelectric-list@matronics.com> >> Sent: Wednesday, November 22, 2006 11:03 AM >> Subject: Re: AeroElectric-List: Homebrew AHRS? >> >> >>> <sales@6440autoparts.com> >>> >>> I personally don't see the sense in spending >>> $2000-$5000 building your own AHRS according to that website when a >>> Dynon or GRT etc. can be bought ready to go. And they are tried and >>> true. >>> Unless of course one wanted to market one or just does'nt >>> have anything better to do. >>> But of course time permitting one could be built cheap >>> well........ >>> >>> Randy >>> >>> >>> >>> ----- Original Message ----- From: "Ed Anderson" >>> <eanderson@carolina.rr.com> >>> To: <aeroelectric-list@matronics.com> >>> Sent: Tuesday, November 21, 2006 7:39 PM >>> Subject: Re: AeroElectric-List: Homebrew AHRS? >>> >>> >>>> <eanderson@carolina.rr.com> >>>> >>>> Hi Sean, >>>> >>>> Try out this URL http://www.aerospectra.com/efis/svis.htm >>>> >>>> Dr Jim Hauser has a book worth getting on the basics as well as the >>>> components to get started. >>>> >>>> Ed >>>> >>>> Ed Anderson >>>> Rv-6A N494BW Rotary Powered >>>> Matthews, NC >>>> eanderson@carolina.rr.com >>>> http://members.cox.net/rogersda/rotary/configs.htm#N494BW >>>> http://www.dmack.net/mazda/index.html >>>> ----- Original Message ----- From: "Sean Stephens" >>>> <sean@stephensville.com> >>>> To: <aeroelectric-list@matronics.com> >>>> Sent: Tuesday, November 21, 2006 1:04 PM >>>> Subject: AeroElectric-List: Homebrew AHRS? >>>> >>>> >>>>> <sean@stephensville.com> >>>>> >>>>> I've been scouring Google trying to find literature, schematics, >>>>> etc. on building an AHRS/ADAHRS. I've been unable to find >>>>> anything that would get me jump-started on a homebrew project. >>>>> >>>>> If anyone has links that would help I'd appreciate it. >>>>> >>>>> -Sean >>>>> >>>>> >>>>> >>>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>> >>> >>> >>> >>> >>> >> > >


    Message 26


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    Time: 02:52:29 PM PST US
    From: "Ed Anderson" <eanderson@carolina.rr.com>
    Subject: Re: Homebrew AHRS?
    I agree David, The MEMS accelerometers and gyros certain are making very capable autopilots possible at very reasonable prices. Hummm. Ed ----- Original Message ----- From: "David M." <ainut@hiwaay.net> Sent: Wednesday, November 22, 2006 5:32 PM Subject: Re: Fw: AeroElectric-List: Homebrew AHRS? > > Great things are being done now with MEMS, and at just a few dollars per > function. > > David M. > > > Ed Anderson wrote: > >> <eanderson@carolina.rr.com> >> >> >> >> >>> Your correct, Randy, assuming that the only objective/goal is to have >>> an AHRS in your panel. >>> >>> But, some simply want to continue the "educational" goal of Amateur >>> build aircraft by expanding into other associated areas. I designed and >>> built my own EFI Fuel Monitoring System which uses no fuel flow >>> transducer - yes, the parts were certainly cheaper than a purchased >>> one - but, if I included even a modest value for my time - then the >>> commercial one would have been cheaper {:>). But, the goal was not just >>> to build my own, but to learn to design,build and program using >>> microchips. >>> >>> I've just completed a design and prototype for an AOA indicator - again, >>> not because one could not be purchased at a reasonable price - but >>> simply because I enjoy learning new things and building. >>> >>> Different strokes for different folks. >>> >>> Ed >>> Ed Anderson >>> Rv-6A N494BW Rotary Powered >>> Matthews, NC >>> eanderson@carolina.rr.com >>> http://members.cox.net/rogersda/rotary/configs.htm#N494BW >>> http://www.dmack.net/mazda/index.html >>> >>> ----- Original Message ----- From: "6440 Auto Parts" >>> <sales@6440autoparts.com> >>> To: <aeroelectric-list@matronics.com> >>> Sent: Wednesday, November 22, 2006 11:03 AM >>> Subject: Re: AeroElectric-List: Homebrew AHRS? >>> >>> >>>> <sales@6440autoparts.com> >>>> >>>> I personally don't see the sense in spending $2000-$5000 >>>> building your own AHRS according to that website when a Dynon or GRT >>>> etc. can be bought ready to go. And they are tried and true. >>>> Unless of course one wanted to market one or just does'nt >>>> have anything better to do. >>>> But of course time permitting one could be built cheap >>>> well........ >>>> >>>> Randy >>>> >>>> >>>> >>>> ----- Original Message ----- From: "Ed Anderson" >>>> <eanderson@carolina.rr.com> >>>> To: <aeroelectric-list@matronics.com> >>>> Sent: Tuesday, November 21, 2006 7:39 PM >>>> Subject: Re: AeroElectric-List: Homebrew AHRS? >>>> >>>> >>>>> <eanderson@carolina.rr.com> >>>>> >>>>> Hi Sean, >>>>> >>>>> Try out this URL http://www.aerospectra.com/efis/svis.htm >>>>> >>>>> Dr Jim Hauser has a book worth getting on the basics as well as the >>>>> components to get started. >>>>> >>>>> Ed >>>>> >>>>> Ed Anderson >>>>> Rv-6A N494BW Rotary Powered >>>>> Matthews, NC >>>>> eanderson@carolina.rr.com >>>>> http://members.cox.net/rogersda/rotary/configs.htm#N494BW >>>>> http://www.dmack.net/mazda/index.html >>>>> ----- Original Message ----- From: "Sean Stephens" >>>>> <sean@stephensville.com> >>>>> To: <aeroelectric-list@matronics.com> >>>>> Sent: Tuesday, November 21, 2006 1:04 PM >>>>> Subject: AeroElectric-List: Homebrew AHRS? >>>>> >>>>> >>>>>> <sean@stephensville.com> >>>>>> >>>>>> I've been scouring Google trying to find literature, schematics, etc. >>>>>> on building an AHRS/ADAHRS. I've been unable to find anything that >>>>>> would get me jump-started on a homebrew project. >>>>>> >>>>>> If anyone has links that would help I'd appreciate it. >>>>>> >>>>>> -Sean >>>>>> >>>>>> >>>>>> >>>>>> >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> >>>> >>>> >>>> >>>> >>>> >>>> >>> >> >> >> >> >> >> >> >> >> > > >


    Message 27


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    Time: 03:06:40 PM PST US
    Subject: Re: 24V 12V grounds
    From: flyadive@aol.com
    One more time! There is NO SUCH FREEKEN thing as a GROUND LOOP in a DC circuit. If you truly believe there is Design one so I can build it and you can prove me wrong. OR tell the poor questioning soul how to "carefully crafted locations designed to minimize the number of grounds and risks for ground-loop noise." Ya CAN'T because each plane is different the wire runs vary and there is NO SUCH FREEKEN thing as a GROUND LOOP in a DC circuit. Barry Yes - I am still monitoring the list, if for no other purpose than to BUST MYTHS! ==================================================== -----Original Message----- From: nuckollsr@cox.net Sent: Tue, 21 Nov 2006 10:39 PM Subject: Re: AeroElectric-List: 24V 12V grounds At 05:02 PM 11/21/2006 -0800, you wrote: >I have a question and I'm in search of an answer. I have a 24V system with >a 24/12 volt 15A converter . Can the output ground of the converter (12V) >use the same single point ground as the 24V, or is it necessary to supply >a second dedicated ground point for the 12V ? Tie them all together . . . preferably at carefully crafted locations designed to minimize the number of grounds and risks for ground-loop noise. See Figure Z-15 in . . . http://aeroelectric.com/articles/Rev11/AppZ_R11J.pdf Bob . . . ________________________________________________________________________


    Message 28


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    Time: 03:49:58 PM PST US
    Subject: Re: 24V 12V grounds
    From: "Matt Prather" <mprather@spro.net>
    There's NO SUCH thing as a DC CIRCUIT!!! Ahh.. There's the rub. :) Regards, Matt- > One more time! > > There is NO SUCH FREEKEN thing as a GROUND LOOP in a DC circuit. > > If you truly believe there is Design one so I can build it and you can > prove me wrong. > OR tell the poor questioning soul how to "carefully crafted locations > designed to minimize the number of > grounds and risks for ground-loop noise." > Ya CAN'T because each plane is different the wire runs vary and there is > NO SUCH FREEKEN thing as a GROUND LOOP in a DC circuit. > > Barry > > Yes - I am still monitoring the list, if for no other purpose than to BUST > MYTHS! > ==================================================== > > > -----Original Message----- > From: nuckollsr@cox.net > To: aeroelectric-list@matronics.com > Sent: Tue, 21 Nov 2006 10:39 PM > Subject: Re: AeroElectric-List: 24V 12V grounds > > > <nuckollsr@cox.net> > > At 05:02 PM 11/21/2006 -0800, you wrote: > >>I have a question and I'm in search of an answer. I have a 24V system >> with >a 24/12 volt 15A converter . Can the output ground of the converter >> (12V) >use the same single point ground as the 24V, or is it necessary to >> supply >a second dedicated ground point for the 12V ? > > Tie them all together . . . preferably at carefully > crafted locations designed to minimize the number of > grounds and risks for ground-loop noise. See Figure > Z-15 in . . . > > http://aeroelectric.com/articles/Rev11/AppZ_R11J.pdf > > Bob . . . > > > ________________________________________________________________________ >


    Message 29


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    Time: 04:04:06 PM PST US
    From: Ernest Christley <echristley@nc.rr.com>
    Subject: Re: 24V 12V grounds
    flyadive@aol.com wrote: > One more time! > > There is NO SUCH FREEKEN thing as a GROUND LOOP in a DC circuit. > > If you truly believe there is Design one so I can build it and you can prove me wrong. > OR tell the poor questioning soul how to "carefully crafted locations designed to minimize the number of > grounds and risks for ground-loop noise." > Ya CAN'T because each plane is different the wire runs vary and there is NO SUCH FREEKEN thing as a GROUND LOOP in a DC circuit. > > Barry > > Yes - I am still monitoring the list, if for no other purpose than to BUST MYTHS! > ==================================================== > > You say to-may-to, I say to-mah-to. I've always known a ground-loop as a situation where two devices share an unsymmetrical supply or ground path. The arrangement is such that the voltage across one device will fluctuate due to the operation of the other. +12V -------------------------------/----\- / \ / \ Load 1 Load 2 / \ GND-------/\/\/\/----------/------------/\/\/\/\/------\ I hope the ASCII art come through unscathed. Please use a monospaced font for email. If a high powered strobe were used as Load 1, it's operation would present a residual voltage where it's wiring connected back into the ground line when the light is turned on. This is caused by the fact that all conductors have some resistance (represented by the squiggly lines). The voltage goes away when the light is extinquished. This would change the voltage perceived by Load 2 as the strobe flashes, which would be a bad thing if it were an audio line, because then you'd hear every flash. It's called a ground-loop, because power lines tend to be pulled from a central location, while local grounding is the norm. You may have a different term for this, and use ground-loop to refer to a different phenomena. Please share your point of view, but also be aware that I'm an ignorant American who thinks that my English measurement system serves me just fine, so I'm unlikely to change terminology this week. > > -----Original Message----- > From: nuckollsr@cox.net > To: aeroelectric-list@matronics.com > Sent: Tue, 21 Nov 2006 10:39 PM > Subject: Re: AeroElectric-List: 24V 12V grounds > > > > At 05:02 PM 11/21/2006 -0800, you wrote: > > >> I have a question and I'm in search of an answer. I have a 24V system with >a 24/12 volt 15A converter . Can the output ground of the converter (12V) >use the same single point ground as the 24V, or is it necessary to supply >a second dedicated ground point for the 12V ? >> > > Tie them all together . . . preferably at carefully > crafted locations designed to minimize the number of > grounds and risks for ground-loop noise. See Figure > Z-15 in . . . > > http://aeroelectric.com/articles/Rev11/AppZ_R11J.pdf > > Bob . . . > > > > ________________________________________________________________________ > >


    Message 30


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    Time: 04:11:41 PM PST US
    From: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
    Subject: Re: 24V 12V grounds
    At 06:05 PM 11/22/2006 -0500, you wrote: >One more time! > >There is NO SUCH FREEKEN thing as a GROUND LOOP in a DC circuit. > >If you truly believe there is Design one so I can build it and you can >prove me wrong. >OR tell the poor questioning soul how to "carefully crafted locations >designed to minimize the number of > grounds and risks for ground-loop noise." >Ya CAN'T because each plane is different the wire runs vary and there is >NO SUCH FREEKEN thing as a GROUND LOOP in a DC circuit. > >Barry > I don't need to hypothesize about one because there are countless examples of DC ground loops and the techniques developed to avoid them. All of our temperature measurement devices aboard an airplane used dedicated outbound and return wires so that both signal and ground leads can convey good data to the system having and interest in remote temperatures. To ground the sensor locally would inject voltages not related to the measurement task which are related to airframe resistance combined with ground currents of other systems that flow on the airframe. Very early on in my association with the OBAM aircraft community I got a phone call from a Longez pilot who reported that his CHT, OIL TEMP and OIL Pressure gages read just fine with the alternator off . . . but differed wildly from true readings when the alternator was first turned on and then wiggled around as other accessories were turned on and off. This anecdote is described on pages 5-5 and 5-6 of the 'Connection. Seems the senders for these instruments were locally grounded to crankcase while the instruments were grounded to battery(-) at the nose. The airplane didn't have a starter so the 10AWG ground wire the builder ran from battery(-) to crankcase was sufficient for alternator return . . . but offered a substantial voltage difference between crankcase and battery(-) due to alternator output currents flowing in the wire. This small voltage in a DC GROUND LOOP was responsible for upsetting the ship's engine instruments. Adding a dedicated ground wire for instruments that returned all the way to the crankcase broke the loop and eliminated the problem. Starter generator controllers on all our bizjets feature remote sense conductors for both bus and ground signals that are extended from the controller all the way to to generator's terminals under the nacelle. The use of remote as opposed to local sensing for both bus and ground eliminates any errors of measurement that might be introduced by currents flowing on the airframe. We do this to avoid the DC GROUND LOOP that would most certainly exist were the practice not observed. These are but a handful of dozens of examples of DC Ground Loops that we choose to avoid by judicious architecture of vulnerable systems. >Yes - I am still monitoring the list, if for no other purpose than to BUST >MYTHS! I don't know what you would choose to call the system design errors that would introduce the problems cited above. Perhaps we have a misunderstanding of definitions. The venue in which I've made my living all these years calls these phenomenon "ground loops" and because they're DC signals being upset by DC currents flowing on the airframe, we call them DC GROUND LOOPS. Do you have another name for them? Bob . . .




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