---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Mon 04/06/09: 24 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 02:00 AM - Yahoo! Auto Response (bczygan@yahoo.com) 2. 02:14 AM - incandescent light question (Gilles Thesee) 3. 06:25 AM - Re: incandescent light question (rampil) 4. 06:30 AM - Re: Odyssey Battery Alternative (Speedy11@aol.com) 5. 06:31 AM - Re: Odyssey Battery Alternative (Robert L. Nuckolls, III) 6. 06:42 AM - Re: incandescent light question (Robert L. Nuckolls, III) 7. 07:50 AM - Re: Odyssey Battery Alternative () 8. 08:24 AM - Re: Impossible problem (Ed Mueller) 9. 08:54 AM - Re: Impossible problem (jaybannist@cs.com) 10. 10:38 AM - Re: Odyssey Battery Alternative (Charlie England) 11. 11:03 AM - Re: Impossible problem (Robert L. Nuckolls, III) 12. 11:03 AM - Re: Odyssey Battery Alternative (Robert L. Nuckolls, III) 13. 12:15 PM - Re: incandescent light question (Gilles Thesee) 14. 01:51 PM - Basic wiring questions (Ralph Finch) 15. 02:56 PM - Noise in headset when pressing to talk (Neil France) 16. 03:04 PM - Re: Odyssey Battery Alternative (The Kuffels) 17. 03:58 PM - Re: Noise in headset when pressing to talk (Allan Aaron) 18. 06:16 PM - VDC Electronics battery charger offer (Sheldon Olesen) 19. 06:36 PM - Re: Odyssey Battery Alternative (Robert L. Nuckolls, III) 20. 08:01 PM - Twisted Pairs, Coils, and EM Fields (Gregory Clawson) 21. 08:04 PM - [Fw: Huuuuuhhhh?] (RScott) 22. 08:09 PM - Re: Odyssey Battery Alternative (Mike Creek) 23. 09:11 PM - Re: [Fw: Huuuuuhhhh?] (Dale Rogers) 24. 09:40 PM - Re: Twisted Pairs, Coils, and EM Fields (Robert L. Nuckolls, III) ________________________________ Message 1 _____________________________________ Time: 02:00:22 AM PST US From: bczygan@yahoo.com Subject: AeroElectric-List: Yahoo! Auto Response Hi Friend, How are you doing recently? I would like to introduce you a very good company which I know. Their website is *www.myehomebuy*They can offer you all kinds of Electronic products like laptops, gps,TV LCD,cell phones,ps3,MP3/4, etc........Please take some time to have a check, There must have something you'd like to buy. Their contact email: myehomebuy_service@188.com MSN: myehomebuy-easylife@hotmail.com Hope you have a good mood in shopping from their company! Best Regards Julie! ________________________________ Message 2 _____________________________________ Time: 02:14:56 AM PST US From: Gilles Thesee Subject: AeroElectric-List: incandescent light question Hi Bob and all, The topic has already been adressed, but I was not able to retrieve the messages or Bob's recommendations on preheating. The question recently arose on a French pilot list : when and why is a landing light filament most fragile ? - When hot ? - When cold ? - When heating up ? - When cooling down ? -Why ? Etc... Thanks in advance for any input, Best regards, -- Gilles http://contrails.free.fr ________________________________ Message 3 _____________________________________ Time: 06:25:24 AM PST US Subject: AeroElectric-List: Re: incandescent light question From: "rampil" Gilles, The common wisdom is that most lamp failures occur on start due to three factors: cold filament stiffness heat shock/expansion and 3) flexion of the stiff filament due induction of the magnetic field in the helical filament Ira -------- Ira N224XS Read this topic online here: http://forums.matronics.com/viewtopic.php?p=237963#237963 ________________________________ Message 4 _____________________________________ Time: 06:30:30 AM PST US From: Speedy11@aol.com Subject: AeroElectric-List: Re: Odyssey Battery Alternative Well said, Dale. The rest of us knew what you meant. Stan Sutterfield Do not archive Charlie England wrote: > Dale Rogers wrote: >> Made in mainland (PDRC) China? > > If this is intended to be a political question, it begs another. Have > you bought any gas for your plane or car lately (terrorism)? Or > virtually any other consumer product (China again)? > > I think that it's instructional that around 50 years of economic > isolation of Cuba has left it virtually unchanged in it's government, > economy or human rights. While after 30 years of trade with China it > isn't 'free', but it's a lot closer than it was 30 years ago, and its > people are certainly a bit better off economically. > > I have an 'alternative' view of this stuff. I think that change must > come from within, & if you want to have external influence, the best > way to drive it is to let the citizens see how good it *could* be, > with better government. Charlie, It wasn't ~intended~ to be "political" - more of a QA issue. There's been a lot of contaminated product coming from the PRC. I've seen a lot of poor quality hardware (tools, shop equipment, electronics) coming from there. Dunno if I want my electric-dependent airplane to rely on a battery coming from such an environment. Best regards, Dale R. **************Worried about job security? Check out the 5 safest jobs in a recession. (http://jobs.aol.com/gallery/growing-job-industries?ncid=emlcntuscare00000003) ________________________________ Message 5 _____________________________________ Time: 06:31:15 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Odyssey Battery Alternative At 10:28 PM 4/5/2009, you wrote: > >Charlie England wrote: >>Dale Rogers wrote: >>>Made in mainland (PDRC) China? >> >>If this is intended to be a political question, it begs another. >>Have you bought any gas for your plane or car lately (terrorism)? >>Or virtually any other consumer product (China again)? >> >>I think that it's instructional that around 50 years of economic >>isolation of Cuba has left it virtually unchanged in it's >>government, economy or human rights. While after 30 years of trade >>with China it isn't 'free', but it's a lot closer than it was 30 >>years ago, and its people are certainly a bit better off economically. >> >>I have an 'alternative' view of this stuff. I think that change >>must come from within, & if you want to have external influence, >>the best way to drive it is to let the citizens see how good it >>*could* be, with better government. >Charlie, > >It wasn't ~intended~ to be "political" - more of a QA issue. >There's been a lot of contaminated product coming from the >PRC. I've seen a lot of poor quality hardware (tools, shop >equipment, electronics) coming from there. Dunno if I want >my electric-dependent airplane to rely on a battery coming >from such an environment. Point taken. However, recall there was a time when "Made in Japan" labels gave one pause. We had some discussions here on the List about Harbor Fright's quality. Bottom line is that for any emerging technology, process or manufacturing culture, there will ALWAYS be those who's ambitions exceed their capabilities or willingness to accomplish the best-we- know-how-to-do. Shucks we see this today with "Made in USA" products. Why should we be having startup brownout discussions on otherwise perfectly wonderful appliances? Folks who rely on ANY words on any label to do a trade study are at risk for being disappointed. At the same time, those who automatically reject any product based on perceptions of a class of manufacturers are at risk of expending $time$ with poor return on investment. Folks who promulgate product avoidance based on culture are doing a disservice to those within that culture who are honestly striving to be competitive. Competition: the free market principal that brought us monster ram for pennies, gigaflop processors for dollars and $100 hand-helds that will find your driveway in zero-zero fog. I've seen stuff at H.F. that I wouldn't buy. I have a number of H.F. machine tools in my shop that service my needs nicely. A $350 lathe paid for itself in the first job! That was 7 years ago and it's still doing what I need done within limits of its design. Discussions here on the List can add the most value for its members by evaluating specific products from ANY source based on demonstrated price/performance benchmarks. Advice that paints a product with a brush dipped into cultural perceptions is demonstrably lacking in foundation and places top performers in that culture at a capriciously invented disadvantage. Further, while we may have disagreements with and even have reason to be fearful of governments (our own not withstanding!) recall that there are folks who design, build and sell products from all parts of the world who would probably like to be building an airplane in THEIR garage too. Finally, if it's a part with failure implications for an uncomfortable arrival with the earth . . . isn't that why failure tolerance is among our design goals? Bob . . . ----------------------------------------) ( . . . a long habit of not thinking ) ( a thing wrong, gives it a superficial ) ( appearance of being right . . . ) ( ) ( -Thomas Paine 1776- ) ---------------------------------------- ________________________________ Message 6 _____________________________________ Time: 06:42:41 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: incandescent light question At 04:12 AM 4/6/2009, you wrote: > > >Hi Bob and all, > >The topic has already been adressed, but I was not able to retrieve >the messages or Bob's recommendations on preheating. > >The question recently arose on a French pilot list : when and why is >a landing light filament most fragile ? >- When hot ? >- When cold ? Tungsten passed from a brittle to ductile state as it rises in temperature. The legacy automotive lamp filaments were most vulnerable to vibration stresses while cold. >- When heating up ? Thermal stresses are highest during heat-up transition. >- When cooling down ? >-Why ? Modern halogen lamps are MUCH more robust than their ancestors. So much so that concerns about inrush limiting are almost insignificant in terms of adding to the service life of a lamp. Even when the halogen lamps are used in a wig-wag system, they do not cool enough between flashes to suffer a deleterious inrush current with each flash. See: http://www.aeroelectric.com/Pictures/Curves/Exemplar_Incandescent_Lamp_Inrush.gif http://www.aeroelectric.com/Pictures/Curves/Wig_Wag_Currents.jpg For new design, I'm certain that the builder will experience very good service life using modern automotive halogen lamps operating without benefit of inrush limiting. Bob . . . ----------------------------------------) ( . . . a long habit of not thinking ) ( a thing wrong, gives it a superficial ) ( appearance of being right . . . ) ( ) ( -Thomas Paine 1776- ) ---------------------------------------- ________________________________ Message 7 _____________________________________ Time: 07:50:59 AM PST US Subject: RE: AeroElectric-List: Odyssey Battery Alternative From: Bob, Thanks for the dissertation on batteries J Actually this is very helpful. If dry cell or sealed batteries are indeed using the same old technology as the slosh type, then the extra $$ are indeed a complete waste of money, yes? I suppose they do a bit of marketing with the carbon fibre casings etc., but is there no better mouse trap hiding in there somewhere? I do not have the Braille factory specs, but that would be an interesting read. My main interest is their lower weight and smaller size. That takes more than marketing. There is nothing to say the BB battery at < $50 would not provide the same performance albeit without the lower internal resistance. I may be confused, but isn't cranking power what we want in batteries? When it's 10 degrees outside and I've had my ship plugged in for 30 minutes, I don't want to hear ra-ra-ra after just one try. If they can boost cranking power by 30 percent, why wouldn't you want that? If I lived in Southern CA, perhaps I wouldn't care. A mission specific thing. The experience of one of our builders has shown that turning on the avionics 5 minutes before starting has disabled the Odyssey's ability to the point where it will not provide enough cranking power to turn over the engine. He flies a Jabaru 230 with the Jabaru 6-cylinder engine. I have not put a meter on the draw (I will), but I did learn that he has two GRT displays installed which require a heartbeat be maintained from the battery at all times. As you may know the GRT does not support internal battery backup directly. I already own an Odyssey and I'm not going to toss it in the trash but I will meter it and report on its performance later. Nevertheless, I will add a second battery to feed the Aux bus and the dual Lightspeed ignition in the event the rest of Z-13/8 fails to co-operate while flying over the airplane eating PA woods at night. Glenn From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Robert L. Nuckolls, III Sent: Saturday, April 04, 2009 10:07 AM Subject: Re: AeroElectric-List: Odyssey Battery Alternative At 07:28 AM 4/4/2009, you wrote: Thanks, Definitely something to think about when it becomes replacement time. My 680 is brand new - I replaced a four year old one that I had beaten up pretty hard during the construction process. The new one seems to do fine at the present - but I keep a Battery Hawk on it between flights so it's always topped off. Why did you replace it? Was it sent to recycle because it's capacity had fallen below your e-bus run-time benchmark or because it didn't crank the engine any more? This thread started with the following statements: "Several of our hangar members have been experiencing trouble with reserve power using the popular Odyssey 680 battery. If running avionics and the like prior to starting (even briefly), the reserve power on these things really take a hit." "I am not a huge fan of jump starting an aircraft or starting on reduced voltage when my craft is already electrically dependent and the taking off into a emergency situation with less than full reserve." "Recently I found an option which has more cranking amps, (better A.H. value and about the same weight (or less). Albeit slightly more expensive, they may offer a good alternative for 680 users who find their batteries run down a bit too fast for their liking." "Reserve power" speaks to watt-seconds of energy contained when fully charged. This is closely related to the battery's rated capacity in Ampere- Hours although apparent capacity can vary widely depending on loads due to the battery's internal losses (conduction = 1/resistance). Double the load on a battery and internal losses go up by a factor of 4. The terms "briefly" and "really takes a hit" are not quantified. Nor were the pre-cranking loads for operation of "running avionics and the like". So we're not privy to the numbers that define expected/desired battery performance. We also don't know the numbers that drove perceptions of "experiencing trouble". My words are not intended to cause anyone discomfort but it is helpful to understand the numbers behind a proposed exchange of product. Then each of you needs to decide how the exchange will improve on your personal expectations for system performance and the amount of $time$ you're willing to expend as a cost of ownership. The Braille batteries appear to have been fine tuned for lower internal resistance. This is suggested by the greater "cranking" or "pulse" current ratings. But in terms of capacity, watt-seconds of energy stored is pretty much set by how many pounds of reactants (lead) is in the battery. Indeed, their a.h. ratings/pound of product weight are right in line with everybody else's products. They speak to the "conductance" test and something new . . . which it is not. The test is easily performed with modern "battery analyzers". An example of this instrument can be seen at: http://www.midtronics.com/default.asp where we find no less than 15 different models of device selling for hundreds of dollars. What your buying with these capable instruments is convenience of light weight, compact size, digital readout, and perhaps some predictions of service-life. However, the data gathered is the same as that which you would get from this piece of arcane technology from Harbor Freight for about $60. http://aeroelectric.com/Pictures/Battery_Testers/HF91129_4.jpg The later device requires some understanding and skill but ultimately is a BETTER measure of cranking performance because the test loads are REAL and not extrapolated from short, pulsed values in the digital instrument. What does internal resistance (reciprocal of conductance) have to do with capacity? Nothing. Capacity is related to pounds of chemistry available to store energy. The efficiency with which that energy can be extracted for useful purposes IS affected by internal resistance. This is discussed in some detail in the battery chapter update published at: http://aeroelectric.com/R12A/02_Battery_12A2.pdf Without knowing the nature and magnitude of "experiencing trouble" which drives the decision to seek a more robust battery, we're not able to advance this deliberation based on physics and comparative measurements. I can only hypothesize as follows: The perceptions of poor battery performance are probably based on a pre-cranking battery load that is unnecessarily large. Without an e-bus and the ability to get your ATIS data and a departure clearance, then flipping on the battery master burdens the battery with loads that far exceed present requirements. Keep in mind too that the energy required to get a well tuned engine started is but a few percent of a battery's capacity. This battery voltage/current curve . . . http://www.aeroelectric.com/Pictures/Curves/turbine_start_a.jpg was taken from a Beechjet engine start. It begins with over 800A and tapers to 300A over a period of 27 seconds. After all that abuse, the battery is tapped for perhaps 6% of contained energy. I agree that we're comparing apples and oranges with respect to types of engines and design goals for two vastly different airplanes. But I'll suggest that if somebody is having trouble getting and engine started -OR- has seriously depleted a battery during pre-flight operations because of loads imposed before the alternator comes on line . . . a serious reevaluation of design goals and operating procedures is called for. Back to the Braille battery product. They probably do conform to marketing hype concerning a lower internal resistance. This is easily demonstrated with and instrument not unlike the Harbor Freight device cited above. Now the question: What does the more expensive battery buy you in terms of cost of ownership? Now that you've installed the Lexus of batteries, how are you going to modify your rules of ownership and operation for the purpose of meeting design goals for your airplane? Are you going to do periodic capacity checks to make well considered decisions as to when the battery needs replacing? Is it a reasonable expectation that $time$ to maintain plust $time$ to buy the higher price battery will be SMALLER than $time$ to buy an el-cheepo battery and replace it every year? Finally, rushing off to buy this premium battery product may not get you the same return on investment expected by those who are "experiencing trouble" with their current battery choices. Without an analysis of how their disappointment arises, there's no guarantee that YOUR purchase of the more robust battery will produce a good return on your investment. Bob . . . ________________________________ Message 8 _____________________________________ Time: 08:24:41 AM PST US From: Ed Mueller Subject: Re: AeroElectric-List: Impossible problem Jay, Any luck with the problem? You might consider that maybe the original wiring isn't correct, only appeared to be. Years ago, I wired a project (not airplane related) and it worked fine. Couple years later made a minor alteration and all sorts of strange things started happening. Turned out the original wiring was incorrect. Ed On Apr 1, 2009, at 4:08 PM, jaybannist@cs.com wrote: > Bob, > > Thanks. I had about decided that the laws of physics HAD been > repealed, or that I was losing my ever-lovin' mind ! Now that you > have confirmed that those laws are still intact; I know that my next > step is to take all the wiring off those two switches. Then I will > positively identify each wire before I reinstall it on the switch. > I'll let you know if that fixes the problem. > > Thanks again - Jay > > > -----Original Message----- > From: Robert L. Nuckolls, III > To: aeroelectric-list@matronics.com > Sent: Wed, 1 Apr 2009 1:53 pm > Subject: Re: AeroElectric-List: Impossible problem > > At 12:37 PM 4/1/2009, you wrote: > > >> My MAIN source of concern is that EVERYTHING >> worked properly before I made this change; and the >> ONLY thing I changed was the source of power to >> the coil and fuel pump switches. >> >> Jay > Understand. Without being able to put my > hands on the problem, the most I (or anyone > else) can do is hypothesize about a lot > of things . . . the majority of which will > be irrelevant/wrong. > > The laws of physics do not shift their > effects to confound us. There is a specific > reason why you are experiencing the problem > you cited. If you've ever played the board game > Clue, you'll understand that arriving at root > cause is a distillation of facts first to > eliminate those that do not fit into an > explanation of effects and finally identify the > order in which remaining facts explain the > cause for symptoms you've identified. > > Snip off the tie wraps, check the wires, follow > the path from bus to appliance with a voltmeter > probe . . . nobody sez it's easy . . . but it > works every time. > > Bob . . . > > > Email message sent from CompuServe - visit us today at > http://www.cs.com > > ________________________________ Message 9 _____________________________________ Time: 08:54:41 AM PST US Subject: Re: AeroElectric-List: Impossible problem From: jaybannist@cs.com Ed, I think you are right. It did work before the change, but that might have just been dumb luck. My airplane is hangered 40 miles and an hour's drive from my home, right through the middle of Dallas. The upshot is that I don't work on it as often as I want to, or should.? My next trip (this week) will be to do a BUNCH of re-wiring.? Stay tuned. Jay? ?? -----Original Message----- From: Ed Mueller Sent: Mon, 6 Apr 2009 10:22 am Subject: Re: AeroElectric-List: Impossible problem ? Jay,? ? ? Any luck with the problem? You might consider that maybe the original wiring isn't correct, only appeared to be. Years ago, I wired a project (not airplane related) and it worked fine. Couple years later made a minor alteration and all sorts of strange things started happening. Turned out the original wiring was incorrect.? ? Ed? ? On Apr 1, 2009, at 4:08 PM, jaybannist@cs.com wrote:? ? > Bob,? >? > Thanks. I had about decided that the laws of physics HAD been > repealed, or that I was losing my ever-lovin' mind !? Now that you > have confirmed that those laws are still intact;? I know that my next > step is to take all the wiring off those two switches.? Then I will > positively identify each wire before I reinstall it on the switch.? > I'll let you know if that fixes the problem.? >? > Thanks again - Jay? >? ________________________________________________________________________ Email message sent from CompuServe - visit us today at http://www.cs.com ________________________________ Message 10 ____________________________________ Time: 10:38:36 AM PST US From: Charlie England Subject: Re: AeroElectric-List: Odyssey Battery Alternative ________________________________ From: Dale Rogers Sent: Sunday, April 5, 2009 10:28:08 PM Subject: Re: AeroElectric-List: Odyssey Battery Alternative Charlie England wrote: > Dale Rogers wrote: >> Made in mainland (PDRC) China? > > If this is intended to be a political question, it begs another. Have you bought any gas for your plane or car lately (terrorism)? Or virtually any other consumer product (China again)? > > I think that it's instructional that around 50 years of economic isolation of Cuba has left it virtually unchanged in it's government, economy or human rights. While after 30 years of trade with China it isn't 'free', but it's a lot closer than it was 30 years ago, and its people are certainly a bit better off economically. > > I have an 'alternative' view of this stuff. I think that change must come from within, & if you want to have external influence, the best way to drive it is to let the citizens see how good it *could* be, with better government. Charlie, It wasn't ~intended~ to be "political" - more of a QA issue. There's been a lot of contaminated product coming from the PRC. I've seen a lot of poor quality hardware (tools, shop equipment, electronics) coming from there. Dunno if I want my electric-dependent airplane to rely on a battery coming from such an environment. Best regards, Dale R. Ahh, yes, that makes sense; sorry for the misunderstanding. I wonder where the higher priced ones are made. One thing I did notice is that the internal resistance is rather high; from something like 11 to 16 mOhms. IIRC, the Odessey is closer to 6 mOhms. I'm using a similarly rated battery in my RV-4 (Lyc O-320) & it cranks 'ok' but I doubt it would be up to the task on a hi compression IO360. Charlie ________________________________ Message 11 ____________________________________ Time: 11:03:45 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Impossible problem At 10:52 AM 4/6/2009, you wrote: >Ed, > >I think you are right. It did work before the change, but that might >have just been dumb luck. > >My airplane is hangered 40 miles and an hour's drive from my home, >right through the middle of Dallas. The upshot is that I don't work >on it as often as I want to, or should. My next trip (this week) >will be to do a BUNCH of re-wiring. Stay tuned. Ed beat me to it. I was about to ask too. We're all interested in what you find out! Bob . . . ----------------------------------------) ( . . . a long habit of not thinking ) ( a thing wrong, gives it a superficial ) ( appearance of being right . . . ) ( ) ( -Thomas Paine 1776- ) ---------------------------------------- ________________________________ Message 12 ____________________________________ Time: 11:03:45 AM PST US From: "Robert L. Nuckolls, III" Subject: RE: AeroElectric-List: Odyssey Battery Alternative At 09:48 AM 4/6/2009, you wrote: >Bob, > >Thanks for the dissertation on batteries J Actually this is very >helpful. If dry cell or sealed batteries are indeed using the same >old technology as the slosh type, then the extra $$ are indeed a >complete waste of money, yes? No. All lead-acid batteries use lead, lead dioxide, lead sulfate, sulfuric acid and water to craft a reversible electrical energy storage system. http://en.wikipedia.org/wiki/Lead-acid_battery Fabrication methods that exploit this reaction have seen huge evolutionary steps since the time that Plante' first described the phenomenon in 1859 (before the civil war!) Even during my short experience with lead-acid technology (my first car was a 6v, '41 Pontiac acquired in 1961) we've see amazing improvements in robusness, volumetric efficiency, electrical efficiency, ease of integration and cost of ownership for this venerable process. >I suppose they do a bit of marketing with the carbon fibre casings >etc., but is there no better mouse trap hiding in there somewhere? I >do not have the Braille factory specs, but that would be an >interesting read. My main interest is their lower weight and smaller >size. That takes more than marketing. There is nothing to say the BB >battery at < $50 would not provide the same performance albeit >without the lower internal resistance. I may be confused, but isn't >cranking power what we want in batteries? When it's 10 degrees >outside and I've had my ship plugged in for 30 minutes, I don't want >to hear ra-ra-ra after just one try. If they can boost cranking >power by 30 percent, why wouldn't you want that? If I lived in >Southern CA, perhaps I wouldn't care. A mission specific thing. You're speaking in non-quantified concerns, conditions and design goals. Yes, it's probably a given that a $200 battery has features justifying its increases in cost over a $50 battery of the same capacity. Do you need and/or can you exploit a 30% increase in cranking power? If you arbitrarily say "yes" . . . then perhaps an upgrade to Braille products is selling your design goals short. How about a ni-cad? Those are super cranking batteries . . . but they have trade-offs. > >The experience of one of our builders has shown that turning on the >avionics 5 minutes before starting has disabled the Odyssey's >ability to the point where it will not provide enough cranking power >to turn over the engine. He flies a Jabaru 230 with the Jabaru >6-cylinder engine. I have not put a meter on the draw (I will), but >I did learn that he has two GRT displays installed which require a >heartbeat be maintained from the battery at all times. As you may >know the GRT does not support internal battery backup directly. Okay. What is the capacity of the battery he's using? How large are his avionics loads? Is he just running the necessary electro-whizzies for pre-flight . . . or is the whole panel lit up? 5 minutes is a long time to set there with the panel all lit up. This battery is supposed to carry e-bus loads for how long? Minutes, an hour? THREE hours? Your narrative doesn't inform us sufficiently to offer considered advice. If a 5-minute panel load is degrading cranking performance, the FIRST question can be answered only by capacity and load testing the battery. There's a high probability that his battery is trashed. But if his panel loads are say, 50 amps . . . AND assuming that the 5-minute pre-flight ops are part of his design goals, then let's see . . . The PC680 is rated for 7 milliohms internal resistance and a 20 hour capacity of 17 a.h. We don't have performance curves for the PC680 but the ratings are similar to this battery . . . http://www.aeroelectric.com/Pictures/Curves/17AH_12V_Capacity_vs_Load.gif Gee, 50A of panel load is going whack the battery pretty hard in 5 minutes. Okay how about a 17A panel load. Hmmm . . . 5 minutes of operation should leave plenty of snort to crank the engine. Lighter loads are still more attractive. > >I already own an Odyssey and I'm not going to toss it in the trash >but I will meter it and report on its performance later. >Nevertheless, I will add a second battery to feed the Aux bus and >the dual Lightspeed ignition in the event the rest of Z-13/8 fails >to co-operate while flying over the airplane eating PA woods at night. If that design philosophy assuages your concerns, by all means. My point is that these systems operate based on easily deduced and interpreted numbers. Just for grins, if you do have a capacity meter, fully charge your battery, do a standard preflight, crank the engine . . . say twice without turning the alternator on. Shut everything down and THEN do a capacity test at the discharge level appropriate to your endurance loads. If you find that the system falls short on design goals, perhaps you DO need a different battery . . . but the upgrade may have more to do with CAPACITY than it does with getting the engine started. Given that were comparing TWO 17 a.h. batteries, perhaps the upgrade you're anticipating would have an exceedingly poor return on investment. It concerns me that with two engine-driven power sources, a battery with an exemplar reputation, and some form of metering for battery condition that you're still not comfortable with the as-installed system. This suggests that you've not created, tested and are maintaining a plan-a, plan-b, plan-c approach to failures. This leaves you in the unhappy position of (1) constantly worrying; a lack of confidence based on lack of knowledge and (2) being ready to buy some new electro-whizzy because of some perceived incremental increase in performance described in their 4-color marketing brochures. Bob . . . ________________________________ Message 13 ____________________________________ Time: 12:15:27 PM PST US From: Gilles Thesee Subject: Re: AeroElectric-List: incandescent light question Robert L. Nuckolls, III a crit : > > Tungsten passed from a brittle to ductile state > as it rises in temperature. The legacy automotive > lamp filaments were most vulnerable to vibration > stresses while cold. Bob, Ira and all, Thanks for your response. Best regards, -- Gilles http://contrails.free.fr ________________________________ Message 14 ____________________________________ Time: 01:51:06 PM PST US From: "Ralph Finch" Subject: AeroElectric-List: Basic wiring questions I have landing/taxi lights, LED nav lights, a Bob Archer VOR antenna, and an APRS tx/rx antenna in the ends of the wings of an RV-9A (one antenna in each tip). 1. For the powered items, can I run a single positive wire of adequate size to a terminal block, then feed the devices from the block? 2. For the antennas, yes they will be using coax, but should I nevertheless try to run the coax physically separate from the power wires? In addition to the above power wire I have a 3-wire bundle run from the strobe power supply in the fuselage to the wing-tip strobe lights. I installed a conduit about 18 inches away from the Vans wire holes for this purpose. Thanks, Ralph Finch Davis, CA RV-9A QB-SA ________________________________ Message 15 ____________________________________ Time: 02:56:49 PM PST US From: "Neil France" Subject: AeroElectric-List: Noise in headset when pressing to talk Hello listers, I hope you can help me figure out a small problem I have please. I have a mk IV Kitfox fitted with a Bendix King KY97A radio coupled to a Flightcom 403mc intercom, which has been in service without trouble for a number of years. The aircraft has not flown for around seven months, and I am putting it back into service. When the pilots side ptt is pressed, there is a loud constant noise through both headsets, when the copilots ptt is pressed, there is no noise. I replaced the wiring and earths to the pilots stick, but it made no difference I then removed the wire from pin no. 7( pilots ptt switch), on the rear of the unit to eliminate the ptt switch and wiring, and substituted a long length of wire which I touched directly to the battery negative, and the noise was still there. I checked the pins and sockets which all look in perfect condition, but cleaned them anyway. If I use the long length of wire from the battery to pin no. 6 (copilot ptt switch ) it works perfectly with no noise. The noise I hear in my headset, is not transmitted , I have checked the radio reception from a hand held radio using different headsets plugged into the pilot and copilot sockets, and reception is perfect with no background noise. Has anyone any ideas what it could be please? Any help would be greatly appreciated, thanks in advance, Neil. ________________________________ Message 16 ____________________________________ Time: 03:04:07 PM PST US From: "The Kuffels" Subject: Re: AeroElectric-List: Odyssey Battery Alternative Don't understand the problem with PC-680 batteries. This is the type supplied by Glasair for their Sportsman kits. No-one has reported any similar experience. Glenn said his friend has two GRTs with the need for a keep alive clock current. Can't find a specification on the GRT web site for this current but most circuits of this type use about 1 ma. But suppose the current is 10 ma. In this case if he hasn't flown in a while this load could significantly deplete the battery (over 10 amp-hours) in only 3 weeks. At least it is worth measuring to determine if this is part of the problem. Tom Kuffel ________________________________ Message 17 ____________________________________ Time: 03:58:20 PM PST US Subject: RE: AeroElectric-List: Noise in headset when pressing to talk From: "Allan Aaron" I had a similar problem and it turned out to be a problem with my lightspeed headset. I send them back to lightspeed and they fixed them at no charge. Allan ________________________________ From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Neil France Sent: Tuesday, 7 April 2009 7:55 AM Subject: AeroElectric-List: Noise in headset when pressing to talk Hello listers, I hope you can help me figure out a small problem I have please. I have a mk IV Kitfox fitted with a Bendix King KY97A radio coupled to a Flightcom 403mc intercom, which has been in service without trouble for a number of years. The aircraft has not flown for around seven months, and I am putting it back into service. When the pilots side ptt is pressed, there is a loud constant noise through both headsets, when the copilots ptt is pressed, there is no noise. I replaced the wiring and earths to the pilots stick, but it made no difference I then removed the wire from pin no. 7( pilots ptt switch), on the rear of the unit to eliminate the ptt switch and wiring, and substituted a long length of wire which I touched directly to the battery negative, and the noise was still there. I checked the pins and sockets which all look in perfect condition, but cleaned them anyway. If I use the long length of wire from the battery to pin no. 6 (copilot ptt switch ) it works perfectly with no noise. The noise I hear in my headset, is not transmitted , I have checked the radio reception from a hand held radio using different headsets plugged into the pilot and copilot sockets, and reception is perfect with no background noise. Has anyone any ideas what it could be please? Any help would be greatly appreciated, thanks in advance, Neil. ________________________________ Message 18 ____________________________________ Time: 06:16:06 PM PST US From: Sheldon Olesen Subject: AeroElectric-List: VDC Electronics battery charger offer Bob, VDC Electronics is offering aviation specific battery chargers at a reduced price if you trade in an a non-aviation charger. Their aviation chargers are temperature compensated so there is no over or undercharging. They claim that the new chargers will increase the battery life. Are regular battery chargers inadequate for the task, especially if the batteries are being replace every year or so? Is this a marketing gimmick or something worthwhile? Sheldon Olesen http://www.batteryminders.com/batterycharger/home.php ________________________________ Message 19 ____________________________________ Time: 06:36:23 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Odyssey Battery Alternative At 04:29 PM 4/6/2009, you wrote: > >Don't understand the problem with PC-680 batteries. This is the >type supplied by Glasair for their Sportsman kits. No-one has >reported any similar experience. Glenn said his friend has two GRTs >with the need for a keep alive clock current. Can't find a >specification on the GRT web site for this current but most circuits >of this type use about 1 ma. But suppose the current is 10 ma. In >this case if he hasn't flown in a while this load could >significantly deplete the battery (over 10 amp-hours) in only 3 >weeks. At least it is worth measuring to determine if this is part >of the problem. > >Tom Kuffel The thread started with an observation that one or more folks where having trouble getting their engine started after a 5 minute pre-starting load of unknown magnitude. An idea was proposed that a particular brand of battery might be a good replacement. It was advertised to have greater cranking capability. This isn't about the goodness of one battery or the badness of another. It's about KNOWING what the design goals are and then deducing why they're not being met. The original problem may be no more profound than the fact that PC680 was shot. Without getting the numbers, all the rest is conversation. Bob . . . ----------------------------------------) ( . . . a long habit of not thinking ) ( a thing wrong, gives it a superficial ) ( appearance of being right . . . ) ( ) ( -Thomas Paine 1776- ) ---------------------------------------- ________________________________ Message 20 ____________________________________ Time: 08:01:31 PM PST US From: Gregory Clawson Subject: AeroElectric-List: Twisted Pairs, Coils, and EM Fields Bob- I recently bought an IVOPROP magnum inflight adjustable propeller; the adjustment is done with an electric motor. The power and ground leads are both approximately 12 feet long, as are the two leads that go from the switch to the carbon brushes. The installation directions explicitly state "Do not cut the wires"; I called IVOPROP and asked if that applied to all four wires, or only the ones going out to the prop. They stated that all the wires should be left alone, as the resistance of the wires was part of the calculation for circuit breaker selection, and shorter wires would result in the breaker tripping more easily. So, I have two pair of 12 fort wires to stow in behind the panel of an RV-7. I don't want simply to coil the wires out of concern for the EM field the coil would produce whenever I'm changing the pitch of the prop. Can I take the power/ground pair and twist them, take the two leads out to the prop and twist them, then twist the two twisted pairs together, and finally stow them in a loose but well-secured coil? Memories from college physics lead me to think the electrons flowing in opposite directions should cancel each others' fields, but those memories are a little hazy. Thank you, Gregory Clawson RV-7, E-6/200, N687LC (res) ________________________________ Message 21 ____________________________________ Time: 08:04:05 PM PST US From: RScott Subject: AeroElectric-List: [Fwd: Huuuuuhhhh?] ________________________________ Message 22 ____________________________________ Time: 08:09:11 PM PST US From: "Mike Creek" Subject: RE: AeroElectric-List: Odyssey Battery Alternative Forgive me for adding more "conversation", but 680's have performed well for me. I use a PC-680 on an O-540 installation. I'm on the second 680 and both have performed well. I trashed the first one during the building process by hitting it with 15 or so full discharges after leaving the master on. Then I overcharged it numerous times with a non-maintaining car charger. It still started the 540 but was getting weak after two months of flying. I put in the second one and it just goes and goes even on cold morning starts. I have to say it has plenty of reserve, but I haven't measured how much. Mike -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Robert L. Nuckolls, III Sent: Monday, April 06, 2009 6:34 PM Subject: Re: AeroElectric-List: Odyssey Battery Alternative At 04:29 PM 4/6/2009, you wrote: > >Don't understand the problem with PC-680 batteries. This is the >type supplied by Glasair for their Sportsman kits. No-one has >reported any similar experience. Glenn said his friend has two GRTs >with the need for a keep alive clock current. Can't find a >specification on the GRT web site for this current but most circuits >of this type use about 1 ma. But suppose the current is 10 ma. In >this case if he hasn't flown in a while this load could >significantly deplete the battery (over 10 amp-hours) in only 3 >weeks. At least it is worth measuring to determine if this is part >of the problem. > >Tom Kuffel The thread started with an observation that one or more folks where having trouble getting their engine started after a 5 minute pre-starting load of unknown magnitude. An idea was proposed that a particular brand of battery might be a good replacement. It was advertised to have greater cranking capability. This isn't about the goodness of one battery or the badness of another. It's about KNOWING what the design goals are and then deducing why they're not being met. The original problem may be no more profound than the fact that PC680 was shot. Without getting the numbers, all the rest is conversation. Bob . . . ----------------------------------------) ( . . . a long habit of not thinking ) ( a thing wrong, gives it a superficial ) ( appearance of being right . . . ) ( ) ( -Thomas Paine 1776- ) ---------------------------------------- ________________________________ Message 23 ____________________________________ Time: 09:11:11 PM PST US From: Dale Rogers Subject: Re: AeroElectric-List: [Fwd: Huuuuuhhhh?] Obviously a product of the public school system. Dale R. COZY MkIV #0497 Ch. 13 RScott wrote: > < newspaper clipping > ________________________________ Message 24 ____________________________________ Time: 09:40:30 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Twisted Pairs, Coils, and EM Fields At 09:58 PM 4/6/2009, you wrote: >Bob- >I recently bought an IVOPROP magnum inflight adjustable propeller; >the adjustment is done with an electric motor. The power and ground >leads are both approximately 12 feet long, as are the two leads that >go from the switch to the carbon brushes. The installation >directions explicitly state "Do not cut the wires"; I called IVOPROP >and asked if that applied to all four wires, or only the ones going >out to the prop. They stated that all the wires should be left >alone, as the resistance of the wires was part of the calculation >for circuit breaker selection, and shorter wires would result in the >breaker tripping more easily. So, I have two pair of 12 fort wires >to stow in behind the panel of an RV-7. This borders on bizarre. I cannot imagine anbody figuring wire length into the sizing of a circuit breaker. >I don't want simply to coil the wires out of concern for the EM >field the coil would produce whenever I'm changing the pitch of the >prop. Can I take the power/ground pair and twist them, take the two >leads out to the prop and twist them, then twist the two twisted >pairs together, and finally stow them in a loose but well-secured >coil? Memories from college physics lead me to think the electrons >flowing in opposite directions should cancel each others' fields, >but those memories are a little hazy. I'm pretty sure just running them in parallel bundles is fine. I've written the company to inquire as to the physics behind any determination of criticality for bundle length. Watch this space. Bob . . . ----------------------------------------) ( . . . a long habit of not thinking ) ( a thing wrong, gives it a superficial ) ( appearance of being right . . . ) ( ) ( -Thomas Paine 1776- ) ---------------------------------------- ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message aeroelectric-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/AeroElectric-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/aeroelectric-list Browse Digests http://www.matronics.com/digest/aeroelectric-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.