---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Mon 11/06/06: 22 ---------------------------------------------------------- Today's Message Index: ---------------------- 0. 12:12 AM - Wow, Cool! New List Feature... [Please Read] (Matt Dralle) 2. 01:03 AM - Questions (phtoxo) 3. 03:13 AM - Re: Looking for a switch (Robert L. Nuckolls, III) 4. 06:30 AM - Re: Sheild pigtails. (Eric M. Jones) 5. 06:30 AM - Re: Questions (Robert L. Nuckolls, III) 6. 06:53 AM - Re: Sheild pigtails. (Robert L. Nuckolls, III) 7. 07:11 AM - Re: Transorb voltage for 14V system (Robert L. Nuckolls, III) 8. 07:21 AM - Re: Questions (phtoxo) 9. 07:21 AM - Re: RF ground (Robert L. Nuckolls, III) 10. 07:30 AM - Re: comic book (Robert L. Nuckolls, III) 11. 08:19 AM - Re: Transorb voltage for 14V system (Peter Mather) 12. 10:46 AM - Slick mag P-lead ground wire (aaa@pacifier.com) 13. 10:59 AM - Load Analysis (Walter Tondu) 14. 02:05 PM - Van's copper foil NAV antenna (Hinde, Frank George (Corvallis)) 15. 02:35 PM - Re: RF ground (Rodney Dunham) 16. 04:01 PM - Re: PROBABLE SPAM> Re: Transorb voltage for 14V system (Paul McAllister) 17. 06:06 PM - Re: LED extension (Rob Wright) 18. 07:16 PM - Re: Re: RF ground (Fiveonepw@aol.com) 19. 08:30 PM - Re: Slick mag P-lead ground wire (Robert L. Nuckolls, III) 20. 08:32 PM - Re: Transorb voltage for 14V system (Robert L. Nuckolls, III) 21. 08:41 PM - Re: Re: Questions (Robert L. Nuckolls, III) 22. 08:42 PM - Re: Load Analysis (Robert L. Nuckolls, III) ________________________________ Message 0 _____________________________________ Time: 12:12:58 AM PST US From: Matt Dralle Subject: AeroElectric-List: Wow, Cool! New List Feature... [Please Read] Dear Listers, By popular suggestion, I've written a substantial new code module for the Matronics Email Lists system. Here's how it works... During each November, I send out quite a few PBS-like "Please make a Contribution to support your List" emails. Wouldn't it be cool if, once a member made a Contribution, they didn't have to receive my support pleas anymore for the rest of that year? Well, that's exactly what I've written! Following this posting, anyone that makes a List Contribution in 2006 will no longer receive my Contribution Pleas for the rest of the year! The best part is this not only applies to the Realtime distribution, but also the Digest distribution! For those that have made a Contribution, the Daily Digest email-version will be invisibly stripped of my requests as well! (Note that my requests will still be present in the online versions of the Digests, List Browse, and on the Forum site.) For those submitting their Contribution by personal Check, please be sure to include your email address along with your Check as this is what is used to determine eligibility. So, in a nutshell, here's how it works: Make a Contribution = No more "Please Make a Contribution" messages! How sweet is that? If that's not a great reason to jump on the Matronics Email List Contribution site and make your donation today, I don't know what is! Don't forget that there are some totally awesome free gifts to be had along with your List Contribution this year!! Don't wait a minute longer to support your Lists! http://www.matronics.com/contribution Thank you for your Support!! Matt Dralle Matronics Email List Administrator ________________________________ Message 1 _____________________________________ Time: 01:03:29 AM PST US Subject: AeroElectric-List: Questions From: "phtoxo" My homebuilt Pioneer 300 equipped with Rotax 912 ULS features a wooden structure for the fuselage, completely covered with a carbon-fibre shell. Wings and tailplane is made of a wooden structure with dacron covering. The fuselage features carbon fibre belly panels for inspection purposes. Questions: which type of antenna's should I use and how do I deal witth the grounding for these? (2x Comm, 1x Nav, 1x Xpond, 1x GPS) How do I deal with the electric grounds - do I bring all the individual grounds to a ground block on the inside of the firewall? Is it advisable to make a separate ground block for the avionics and connect this to the ground block on the inside of the firewall? For starting, which is better - 2 single switches for the ignition and one starter button, or the interlinked 2 switches whereby the lft ignition switch is used for starting as well through off-on-(on) as shown on some Z-diagrams. Is a back-up battery recommended and why? Thanks for any input I may receive from this board. Cees Smit, Germany Read this topic online here: http://forums.matronics.com/viewtopic.php?p=72595#72595 ________________________________ Message 2 _____________________________________ Time: 03:13:52 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Looking for a switch Alan, The functionality you're asking for is provided by a Microswitch 2TL1-10N or 2TL-10L (either locking option will work, you just need to re-wire). These translate to MS27408-4N and MS27408-4L. http://www.aeroelectric.com/Mfgr_Data/Switches/tl_series.pdf Having said that, I agree with Bob's suggestion that you investigate the real risks for inadvertent positioning of the boost pump switch. I've flown a number of aircraft with OFF-LO-HI boost switches . . . none of them offered any sort of "lockout" provisions. These switches will not be easy to find . . . they're not a common catalog item. Bob . . . > > >Good Morning Alan, > >Once again, I am probably venturing where my knowledge >is insufficient, but here goes any way! > >What engine are you running? > >We often have high and low boost pump positions on our >fuel injected Continental engines. It is true that >high boost will kill an engine being operated at low >power, but if the throttle is wide open and the RPM >good and high, high boost may not even be noticed! > >The fuel pressures are not additive. The boost pump >only puts out a bit more pressure than the engine pump >does at high power. In some cases, it is even a bit >less, though still adequate to operate the engine at >full power in the case of an engine driven pump >failure. If you are operating at normal cruise powers >and the high boost is selected, the engine may get a >bit rough, but the power loss will be minimal and the >roughness will get your attention in plenty of time to >take corrective action. Personally, on the Continental >fuel injection system, I see no problem with >nonlocking switches for the boost pump. > >Happy Skies, > >Old Bob >AKA >Bob Siegfried >Stearman N3977A >Downers Grove, IL >LL22 > >--- "Alan K. Adamson" wrote: > > > Adamson" > > > > I'm looking for a locking type switch to be used to > > control 2 positions on a > > fuel pump (low boost and high boost). I need the > > configuration to support > > the down position to be off, the middle to be low > > boost on, and the top > > position to be high boost on, with a lockout between > > low and high boost. > > > > I've done a bit of searching, but so far, haven't > > been able to find what I > > need. Hoping someone here might have seen what I've > > described. I had > > originally thot of using an S700-2-50 as I thought I > > only needed high boost > > for prime. However, in talking with other pilots, > > it now has come to my > > attention that High boost needs to be switchable in > > the event of engine > > driven fuel pump failure and can't simply be > > momentary. The reason I can't > > use a 3 position without lockout, is that low boost > > is normally switched on > > at or above 10K and if you accidentally switched to > > high boost, you'd drown > > the engine. > > > > Any help would be appreciated.... In the morass of > > switches that exist, even > > a good source of a manufacturer and I'll do the leg > > work would be helpful. > > > > Thanks in advance, > > Alan > > > > > > > > > > > > browse > > Subscriptions page, > > FAQ, > > http://www.matronics.com/Navigator?AeroElectric-List > > > > Web Forums! > > > > > > Admin. > > > > > > > > > > > > >-- > > >-- 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 3 _____________________________________ Time: 06:30:38 AM PST US Subject: AeroElectric-List: Re: Sheild pigtails. From: "Eric M. Jones" See: http://www.emcesd.com/semdemos.htm Here is a demonstration of a 5V square wave where the pigtail develops 1.5V across it. At pretty low frequencies too. At high frequencies...your signal has vanished into the ether. The problem is that the reduction of the shield to a pigtail wrecks all the nice electrical characteristics that you paid for by using coaxial cable, by introducing an inductance. Proper termination of coaxial shields involves much more than twisting the shield into a "pigtail"--it involves coupling the shield to the ground or other other conductor with an inductance that is equal to- or lower than- the coax shield. So "pigtails" are for pigs. Let's keep it that way and learn how to do it right. "Every act of conscious learning requires the willingness to suffer an injury to one's self-esteem...." -Thomas Szasz -------- Eric M. Jones www.PerihelionDesign.com 113 Brentwood Drive Southbridge, MA 01550 (508) 764-2072 emjones@charter.net Read this topic online here: http://forums.matronics.com/viewtopic.php?p=72621#72621 ________________________________ Message 4 _____________________________________ Time: 06:30:38 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Questions At 01:01 AM 11/6/2006 -0800, you wrote: > >My homebuilt Pioneer 300 equipped with Rotax 912 ULS features a wooden >structure for the fuselage, completely covered with a carbon-fibre shell. >Wings and tailplane is made of a wooden structure with dacron covering. >The fuselage features carbon fibre belly panels for inspection purposes. >Questions: which type of antenna's should I use and how do I deal witth >the grounding for these? (2x Comm, 1x Nav, 1x Xpond, 1x GPS) >How do I deal with the electric grounds - do I bring all the individual >grounds to a ground block on the inside of the firewall? >Is it advisable to make a separate ground block for the avionics and >connect this to the ground block on the inside of the firewall? >For starting, which is better - 2 single switches for the ignition and one >starter button, or the interlinked 2 switches whereby the lft ignition >switch is used for starting as well through off-on-(on) as shown on some >Z-diagrams. >Is a back-up battery recommended and why? > >Thanks for any input I may receive from this board. May I suggest you acquire a copy of the AeroElectric Connection . . . a publication with whole chapters that discuss topics you've cited. If you have the Z-diagrams, then you already have a sample of the document's usefulness. The Builder's Bookstore offers an e-book version of the 'Connection at http://buildersbooks.com/ You can print the e-book off as needed and on paper/ binder formats of choice. If you have questions or having trouble selecting from multiple philosophies then there's a bunch of folks here on the List who can help you. It's a good idea to ground your questions in some level of pre-understanding before we here on the List begin to expound on our various preferences levels of understanding. 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 5 _____________________________________ Time: 06:53:19 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Sheild pigtails. At 12:18 AM 11/6/2006 -0500, you wrote: > > >How does one use the little pigtails that are designed to bring the shield >of a coax cable out to a wire? The ones I have are from Steinair and have a >special clear heatshrink with a metal ring in the center and a small wire >under the heatshrink and ring that can be attached to a terminal or pin. I >slid the whole works over a stripped coax shield and put a heatgun on it. >The sleeve shrank around the coax just fine but the ring was a bit larger >than the shield and didn't melt like I expected (someone told me it was >solder ring that would melt around the shield and the pigtail wire). Is this >true? Or am I supposed to crimp the metal ring before shrinking the >shrinkwrap. Or what......?????????????? Thanks. These are "Soldersleves" by Tyco/Raychem. They come in a variety of formats. Their use is illustrated in the last frame of an article at: http://aeroelectric.com/articles/pigtail/pigtail.html The devices are described in part in documents at: http://www.aeroelectric.com/Mfgr_Data/Misc/Raychem-Tyco The problem you're having suggests that your heatgun output is too cold and/or insufficiently concentrated on the length of the sleeve. My personal favorite gun right now is by Milwaukee and is similar to the one shown at: http://www.toolfetch.com/Category/Power_Tools/Heat_Guns/8975-6.htm There are over 200 listings for heat guns on ebay right now. Avoid the Milwaukee 1400 . . . looks cool, but only 300 watts. Dual heat guns are handy, variable heat guns are better. 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 _____________________________________ Time: 07:11:56 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Transorb voltage for 14V system At 06:35 PM 11/5/2006 +0000, you wrote: > >What is the optimum voltage of transorb for a 14V system. 15V seems a bit >marginal. 18 seems OK? > >Thanks in anticipation > >Peter I am curious as to why you think you need one. The topic of spikes and other evils on the bus has been discussed here on the list since day-one, but to date, nobody has offered data from a repeatable experiment that illuminates sources, intensities and energy content of any perturbations of interest on an airplane or any other vehicular DC power system. Thus far, proponents of prophylactic measures such as Transorbs, MOVs, etc. have only cited the sales literature for such products that strongly suggest that you buy a lot of their product and sprinkle liberally about your system . . . at least having done so might make you feel good. See: http://www.aeroelectric.com/Mfgr_Data/Semiconductors/AN9312.pdf Keep in mind too that a Transorb rated at 18v goes into a hard limit at over 25 volts when it's "working hard" at it's intended task. See: http://www.aeroelectric.com/Mfgr_Data/Semiconductors/15ke.pdf Just be aware that to date, nobody has come forward with an engineering justification for sprinkling Transorbs around any part of the airplane's electrical system and then explained the simple-ideas that support their proposition. Those who have championed the Transorb most vigorously have overlooked and/or ignored the wide range of clamping voltage when the device is stressed over the full range of its ratings. An 18v Transorb does NOT guarantee that the device being "protected" will not suffer a spiking event that exceeds 18v by a considerable margin. Don't mis-interpret my suggestions here. Transorbs are marvelous devices and I've designed dozens of circuits that utilize these nifty gizmos to stand off the effects of lightning strokes! But the notion that they're useful for much of what folks tend to worry about in little airplanes is not supported in physics or practice. 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 7 _____________________________________ Time: 07:21:39 AM PST US Subject: AeroElectric-List: Re: Questions From: "phtoxo" Sorry Bob, didn't mean to offend any. It is just that most of my questions are somewhat covered, I was looking for more precise answers and why, especially the antennae questions. E.g. is it better to use a bent whip on the belly and try to get a ground plane on the carbon fiber or is it better to use a antennae for composite and built it in the rudder. Why is it better and how do I get the ground for this composite antennae? I'll try to be more precise with my questioning in the future. Regards, Cees Smit. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=72643#72643 ________________________________ Message 8 _____________________________________ Time: 07:21:39 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: RF ground At 07:24 AM 11/4/2006 -0500, you wrote: > > >Fellow Nuckollheads, > >I've been doing a lot of reading on-line concerning eliminating RFI in the >HF band in my mobile 10/11 meter installation. The current wisdom seems to >be to "ground everything" which I am in the process of doing. BUT... All >the ham gurus recommend using tinned braided wire for RF grounding in >preference to the usual copper w/ insulation "hook-up" wire. I can't >figure out why this would matter. And then, of course, the real meat of >the matter... If I do this to my SkyRanger, will it decrease RFI through >my VHF Comm??? > >Rodney in TN Most of my experiences dealing with RFI problems in aircraft have root causes founded in poorly designed hardware or inattention to installation requirements. These often create situations where the owner/operator is struggling to 'band-aid' the system to accommodate the deficiencies over which the fellow has no control. Adding bond straps, shields, moving bundles, etc are all part and parcel of the RFI alchemists ingredients that are OCCASIONALLY components of a recipe for success. A well considered approach to solving a RFI problem requires that you identify the antagonist and deduce the exact propagation mode from antagonist to victim. More often than not, the real success comes from fixing some deficiency in the antagonist or its installation as opposed to "helping" victims live in the unhealthy environment. We need more details about your system: Power levels, antenna and feed line installation, etc. What systems are victimized by the transmitter? Bob . . . ________________________________ Message 9 _____________________________________ Time: 07:30:58 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: comic book At 06:40 PM 11/3/2006 +0000, you wrote: > > >> BNC connectors. I featured this adapter in the comic >> book > >Just to enrich my English language knowledge, what exactly do you mean by >"Comic Book" ? Comic books is a generic term that describes highly illustrated story books with captions on each illustration. Where I work, a "comic book" is a series of illustrations with captions, usually step by step instructions . . . and little (if any) formatted text. For example: http://aeroelectric.com/articles/shldwire/shldwire.html is a "comic book" in the purest sense. This piece could stand alone with its captioned illustrations but I elected to add supporting text . . . http://aeroelectric.com/articles/multiplewires/multiplewires.html and of course, this piece at . . . http://aeroelectric.com/articles/multiplewires/multiplewires.html is simply an article with the occasional supporting illustration. The "comic book" is a powerful teaching tool for guiding the reader through a series of orchestrated steps leading to some goal in fabrication or understanding. 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 10 ____________________________________ Time: 08:19:55 AM PST US From: "Peter Mather" Subject: Re: AeroElectric-List: Transorb voltage for 14V system Bob I'm building a RV9A and using a variant of Z-11 as the electrical system. Basically the endurance bus is provided by a composite design mini-power panel http://www.compositedesigninc.com/Mini_Power.htm except that this has all the electrics connected to it except the alternator field, Critically, the non-switchable load is only a measured 0.8amp for a Dynon D10A and engine instruments. I'm using a IR 125NQ015 diode mounted directly onto the power panel positive bus (this is a great device with 1/4" screw terminal for the incoming feed and its case as the output. This has a VF of only 0.33V so at my full load is only dissipating about 8 Watts. I'm intending to use a 5000W axial transorb across the terminals of the power panel to provide both a level of spike protection but also overvoltage protection. I've conducted experiments with a 9V version of the transorb and demonstrated that I can blow either my endurance bus fuse or my alternator current limiter without damage to the transorb. In other words an overvoltage on the alternator should blow its own fuse and if any transients exist they would also be mopped up. The transorb voltage is obviously critical in this. I don't want it conducting in any normal situation, but do want it to let go as soon as any significant overvoltage condition exists. Without wishing to start any further spike protection or alternator overvoltage wars, I'm very interested in your views on this approach. Best regards Peter ----- Original Message ----- From: "Robert L. Nuckolls, III" Sent: Monday, November 06, 2006 3:11 PM Subject: Re: AeroElectric-List: Transorb voltage for 14V system > > > At 06:35 PM 11/5/2006 +0000, you wrote: > >> >>What is the optimum voltage of transorb for a 14V system. 15V seems a bit >>marginal. 18 seems OK? >> >>Thanks in anticipation >> >>Peter > > I am curious as to why you think you need one. > The topic of spikes and other evils on the bus > has been discussed here on the list since day-one, > but to date, nobody has offered data from a repeatable > experiment that illuminates sources, intensities and > energy content of any perturbations of interest on > an airplane or any other vehicular DC power system. > > Thus far, proponents of prophylactic measures such as > > Transorbs, MOVs, etc. have only cited the sales > literature for such products that strongly suggest > that you buy a lot of their product and sprinkle > liberally about your system . . . at least having done > so might make you feel good. See: > > http://www.aeroelectric.com/Mfgr_Data/Semiconductors/AN9312.pdf > > Keep in mind too that a Transorb rated at 18v goes into > a hard limit at over 25 volts when it's "working hard" > at it's intended task. See: > > http://www.aeroelectric.com/Mfgr_Data/Semiconductors/15ke.pdf > > > Just be aware that to date, nobody has come forward > with an engineering justification for sprinkling Transorbs > around any part of the airplane's electrical system and > then explained the simple-ideas that support their > proposition. Those who have championed the Transorb > most vigorously have overlooked and/or ignored the wide > range of clamping voltage when the device is stressed > over the full range of its ratings. An 18v Transorb > does NOT guarantee that the device being "protected" > will not suffer a spiking event that exceeds 18v by > a considerable margin. > > Don't mis-interpret my suggestions here. Transorbs > are marvelous devices and I've designed dozens of > circuits that utilize these nifty gizmos to stand off > the effects of lightning strokes! But the notion that > they're useful for much of what folks tend to worry about > in little airplanes is not supported in physics or practice. > > > 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 11 ____________________________________ Time: 10:46:47 AM PST US Subject: AeroElectric-List: Slick mag P-lead ground wire From: aaa@pacifier.com I see the P-lead and the ground lug on the back of the Slik mag. I know I need to use a coaxial wire with the center conductor on the P-lead and the braided outer conductor on the ground lug. Two questions: 1) What gage wire do I use. I have some 22 gage coax already run, but is ths big enough. 2) Do I ground the center conducto to a local ground point at the switch on the panel or do I ground it to the coax outer conductor? Thanks Duane Wilson RV9A ________________________________ Message 12 ____________________________________ Time: 10:59:29 AM PST US From: Walter Tondu Subject: AeroElectric-List: Load Analysis I've been receiving requests for a Load Analysis spreadsheet that I created during the build of my RV-7A. I thought I would make it's location public in this forum since most of the requests came from attendees of the 'lectric class. This chart is not guaranteed to be accurate and you should do your own analysis, but his may be a quick start for some of you. http://www.rv7-a.com/LoadAnalysis.xls -- Walter Tondu http://www.rv7-a.com - Flying! http://www.evorocket.com - Building ________________________________ Message 13 ____________________________________ Time: 02:05:32 PM PST US Subject: AeroElectric-List: Van's copper foil NAV antenna From: "Hinde, Frank George (Corvallis)" I also posted in the Vanairforce. I installed the Van's NAV antenna which is a 24" *0.5 strip of copper foil glued to the bottom surface of the right wingtip. I installed my GNS 430 but could not hear the NAV on the ground with the VOR beacon about a mile away. Apparently the beacon should have been easy to pick up. I have a splitter to generate the G/S from the same antenna. Do these antenna's actually work???? I should have checked continuity from the radio to antenna but of course I did'nt! Thanks Frank ________________________________ Message 14 ____________________________________ Time: 02:35:14 PM PST US From: "Rodney Dunham" Subject: AeroElectric-List: Re: RF ground Sorry for the confusion. I'm not trying to solve an RFI problem. I'm setting up the radios and want maxiumum transmit and receive abilities and clear audio on both ends. I was thinking that RF grounds might make the "system" (XCOM/Sonex or CB/F150) more effecient. I was wondering if braided wire bonding straps were really better than stranded wire... and if so, why??? And what's the difference in bonding between VHF (air) versus HF (truck) as far as technic is concerned. I'm just one of those wierdos that thinks it's cool to hear a guy in the pattern in Fort Payne, Alabama when I'm in the pattern in Sweetwater, Tennessee :O) Rodney in TN What's so really cool about flying is all the hobbies within the hobby! DO NOT ARCHIVE _________________________________________________________________ ________________________________ Message 15 ____________________________________ Time: 04:01:03 PM PST US From: "Paul McAllister" Subject: RE: PROBABLE SPAM> Re: AeroElectric-List: Transorb voltage for 14V system Bob et al. Some time ago my aircraft took a lightning hit which damaged many electronic devices, with the exception of the Apollo GX60 and SL70. Now I don't know if this was because these are well designed products or they were just having a lucky day, but my question, would a heavy duty transorb help in a catastrophic even like this ? Paul -----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, November 06, 2006 9:11 AM Subject: PROBABLE SPAM> Re: AeroElectric-List: Transorb voltage for 14V system > >Peter I am curious as to why you think you need one. The topic of spikes and other evils on the bus has been discussed here on the list since day-one, but to date, nobody has offered data from a repeatable experiment that illuminates sources, intensities and energy content of any perturbations of interest on an airplane or any other vehicular DC power system. Thus far, proponents of prophylactic measures such as Transorbs, MOVs, etc. have only cited the sales literature for such products that strongly suggest that you buy a lot of their product and sprinkle liberally about your system . . . ________________________________ Message 16 ____________________________________ Time: 06:06:35 PM PST US From: "Rob Wright" Subject: RE: AeroElectric-List: LED extension Run fiber optic cable; no extra wiring to do. Rob Wright -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Carlos Trigo Sent: Sunday, November 05, 2006 6:07 PM Subject: AeroElectric-List: LED extension I am installing an electronic circuit (Flap Positionong System) which has a 3 colour LED on it. I am puting this box inside the flap enclosure of my RV, thus hiden in a place out of sight. Since I need, for some operations, to see the LED, I am thinking in puting another 3 colour LED somewhere in the panel. How should I connect the pannel LED to the circuit LED? Is it just a 3 wire connection? And both LED's would show the same? TIA Carlos ________________________________ Message 17 ____________________________________ Time: 07:16:41 PM PST US From: Fiveonepw@aol.com Subject: Re: AeroElectric-List: Re: RF ground In a message dated 11/06/2006 4:37:39 PM Central Standard Time, rdunhamtn@hotmail.com writes: I'm just one of those wierdos that thinks it's cool to hear a guy in the pattern in Fort Payne, Alabama when I'm in the pattern in Sweetwater, Tennessee :O) >>> You ain't got no monopoly on weirdness, specially 'round these parts- wierd thing is that I can communicate with planes in the pattern at airports 100+ miles away on my Microair 760 and still can't hear the damn Cherokee with the ancient radio 1/4 mile away in the pattern at my home base- the really cool thing is that the staff at my home base (SYI) is so cool that they hear me coming in and offer alerts as necessary if they know the offending Cherokee is airborne and nearby- anybody else base at an airport that cool? Totally shameless plug: Did I mention what a really COOL airport Shelbyville, TN is? Best gas prices anywhere and if ya stop in, grab aholt of the manager and challenge him to his claim that he is the first dude to loop an F-111... RVs are GREAT & SYI is too! Mark do not archive ________________________________ Message 18 ____________________________________ Time: 08:30:48 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Slick mag P-lead ground wire At 10:42 AM 11/6/2006 -0800, you wrote: > >I see the P-lead and the ground lug on the back of the Slik mag. > >I know I need to use a coaxial wire with the center conductor on the >P-lead and the braided outer conductor on the ground lug. > >Two questions: > >1) What gage wire do I use. I have some 22 gage coax already run, but is >ths big enough. 22 is electrically fine . . . at many TC aircraft facilities, 20 or 18AWG is used simply for mechanical robustness. >2) Do I ground the center conducto to a local ground point at the switch >on the panel or do I ground it to the coax outer conductor? Grounding to shield is preferred. See exemplar schematics in: http://aeroelectric.com/articles/Rev11/AppZ_R11J.pdf 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 19 ____________________________________ Time: 08:32:52 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Transorb voltage for 14V system At 04:16 PM 11/6/2006 +0000, you wrote: > >Bob > >I'm building a RV9A and using a variant of Z-11 as the electrical system. >Basically the endurance bus is provided by a composite design mini-power >panel http://www.compositedesigninc.com/Mini_Power.htm except that this >has all the electrics connected to it except the alternator field, >Critically, the non-switchable load is only a measured 0.8amp for a Dynon >D10A and engine instruments. >I'm using a IR 125NQ015 diode mounted directly onto the power panel >positive bus (this is a great device with 1/4" screw terminal for the >incoming feed and its case as the output. This has a VF of only 0.33V so >at my full load is only dissipating about 8 Watts. >I'm intending to use a 5000W axial transorb across the terminals of the >power panel to provide both a level of spike protection . . . From what spikes? > . . . but also overvoltage protection. I've conducted experiments with > a 9V version of the transorb and demonstrated that I can blow either my > endurance bus fuse or my alternator current limiter without damage to the > transorb. In other words an overvoltage on the alternator should blow its > own fuse and if any transients exist they would also be mopped up. The > transorb voltage is obviously critical in this. I don't want it > conducting in any normal situation, but do want it to let go as soon as > any significant overvoltage condition exists. > >Without wishing to start any further spike protection or alternator >overvoltage wars, I'm very interested in your views on this approach. What kind of alternator? And did you measure the voltage across the transorb just prior to fuse opening and bringing an ov event to heel? Bob . . . ________________________________ Message 20 ____________________________________ Time: 08:41:04 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Re: Questions At 07:19 AM 11/6/2006 -0800, you wrote: > >Sorry Bob, didn't mean to offend any. It is just that most of my questions >are somewhat covered, I was looking for more precise answers and why, >especially the antennae questions. E.g. is it better to use a bent whip on >the belly and try to get a ground plane on the carbon fiber or is it >better to use a antennae for composite and built it in the rudder. Why is >it better and how do I get the ground for this composite antennae? >I'll try to be more precise with my questioning in the future. No problem . . . and if anyone took offense at your question, that's their problem . . . not yours. Now that I understand your question better, I'll try to be more concise as well. Any antenna mounted in proximity to a conductor that is NOT specifically designed to be part of the antenna (i.e. carbon fin) is going to degrade the performance of that antenna from the "ideal" uniformly circular pattern. Carbon fiber as a less than ideal conductor will turn part of your radiated signal into heat instead of allowing it to propagate un-attenuated to the listener's antenna and receiver. Generally speaking, mounting the antenna into the vertical fin is demonstrably poorer performing that one perched on a good ground plane and relatively clear of parasitic conductors. If it were my airplane, I'd go for a top or bottom mount on the fuselage with ground plane radials added to the inside surface of the carbon fiber. This is going to produce the very best we know how to do on the decidedly limiting situation that is the light aircraft. 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 21 ____________________________________ Time: 08:42:53 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Load Analysis I've added Walter's offering to a collection of load analysis examples at: http://www.aeroelectric.com/PPS/Load_Analysis Bob . . . At 01:57 PM 11/6/2006 -0500, you wrote: > >I've been receiving requests for a Load Analysis >spreadsheet that I created during the build of my RV-7A. > >I thought I would make it's location public in this >forum since most of the requests came from attendees of >the 'lectric class. > >This chart is not guaranteed to be accurate and you should >do your own analysis, but his may be a quick start for >some of you. > >http://www.rv7-a.com/LoadAnalysis.xls > >-- >Walter Tondu >http://www.rv7-a.com - Flying! >http://www.evorocket.com - Building > > >-- > > >-- 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 > ---------------------------------------------------------