---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Tue 08/06/13: 22 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 03:53 AM - Re: Re: MIL SPEC spoof (Robert L. Nuckolls, III) 2. 04:04 AM - Re: Battery question (Robert L. Nuckolls, III) 3. 04:26 AM - Re: MIL SPEC spoof (racerjerry) 4. 04:34 AM - Re: Re: roll my own transponder antenna? (Robert L. Nuckolls, III) 5. 04:44 AM - Re: Re: roll my own transponder antenna? (JOHN TIPTON) 6. 05:01 AM - Re: Re: roll my own transponder antenna? (Robert L. Nuckolls, III) 7. 06:54 AM - Invitation to connect on LinkedIn (Thomas Belvin) 8. 07:15 AM - Re: MIL SPEC spoof (Eric M. Jones) 9. 07:38 AM - Re: Battery question (Richard Girard) 10. 08:22 AM - Re: Battery question (Dave Saylor) 11. 11:03 AM - Re: Re: roll my own transponder antenna? (DeWitt Whittington) 12. 12:36 PM - Re: roll my own transponder antenna? (Robert L. Nuckolls, III) 13. 01:39 PM - Re: Re: MIL SPEC spoof (Robert L. Nuckolls, III) 14. 01:50 PM - Re: Navman Fuel Flow Meter (Holger Selover-Stephan) 15. 01:58 PM - Re: Battery question (Robert L. Nuckolls, III) 16. 02:32 PM - Re: Navman Fuel Flow Meter (Charlie England) 17. 03:15 PM - Re: roll my own transponder antenna? (messydeer) 18. 03:44 PM - Re: Re: roll my own transponder antenna? (Tim Andres) 19. 05:43 PM - Re: Navman Fuel Flow Meter (Kelly McMullen) 20. 06:07 PM - Re: Navman Fuel Flow Meter (Ron Walker) 21. 06:53 PM - Re: Navman Fuel Flow Meter (Tim Andres) 22. 08:35 PM - Re: roll my own transponder antenna? (messydeer) ________________________________ Message 1 _____________________________________ Time: 03:53:25 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Re: MIL SPEC spoof >I'm curious though as to how one would begin to write a spec which >took into account "economics and the free market". If you want >companies to bid, you need spec which is factual, you couldn't just >say "brownies such as those commonly available in US supermarkets". Not far wrong I think. In fact, a great many purchases of repackaged commercial off the shelf products have been made over the years by government. The purchase document would call for a quantity of your commercial product repackaged for needs unique to the military. Then ask for samples along with certification that these are the same brownies you can buy on isle 6 at Piggly Wiggly. There is no justification for the creation of a cadre' of micro-czars to craft a specification for a successfully marketed commodity whether it's a box of bolts or a bag of brownies. New development programs have a rich history in entrepreneurial exercise of off-the-shelf talents. Lockheed's Skunk Works is only one of many operations who's successes were achieved not because but in spite of micro-management in by bureaucratic specification. The freedom to operate in a state of "spontaneous order" which allowed talented folks to make day-by-day analysis of progress toward a design goal . . . and turn on a dime if necessary. http://tinyurl.com/l8yyg3m http://tinyurl.com/m3zn7wv I worked in a similar atmosphere at Beech where we designed and built supersonic and subsonic targets. Engineering was right above the factory floor. The division VP was a few steps from my desk. We had "the book" . . . a set of design goals from the customer . . . but how were got there was largely up to the closely cooperative broadly based collection of talents that made up our manufacturing, engineering and management staff. If somebody on the factory floor discovered a problem or had a idea for making a thing better. Consideration, decision and implementation of a useful change was not months or years away but mere days or weeks based on cooperation and agreement of the cognizant talents. I think our engineering meetings were modeled after Kelly Johnson's frequent "how goes it" meetings with his engineers and craftsmen. The point is that an honorable free-market exchange of value conducted in an atmosphere of spontaneous order existed all the way from the day the customer handed us 'the book' to the day the product was launched with goals that it prove/disprove/improve the value weapons systems used against them. The things discussed here on the List are similarly motivated and organized. We exploit the experience and talents of many individuals striving for the elegant solution to design goals. Each of you operates your own skunk works. The success of your efforts is bounded by how well you can sift through ideas and make changes, not by marching in lock-step to artificially generated and mandated specification by individuals who couldn't begin to do what it is that you do best. Bob . . . ________________________________ Message 2 _____________________________________ Time: 04:04:19 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Battery question At 10:10 PM 8/5/2013, you wrote: My understanding is that it takes at least 13.8 volts to charge a 12 volt battery. Last Sunday I was using a Schumacher SC 8010A to charge a 12 volt 20 a.h. AGM battery. The charger started out at 12.5 volts and gradually climbed until after an hour the display was reading 15.5 volts. I disconnected the charger even though when I selected percent of charge it indicated 71 % charged. I used a Fluke VOM to check the battery and it indicated 15.4 volts. The battery was not even warm to the touch so I put the charger back on and continued charging until the battery was at 95% charge at which time the charger was still at 15.5 volts. The battery was barely warm to the touch. Again, with battery disconnected from the charger it tested at 15.4 volts. The battery seemed to work normally when we attempted to start the engine. An idealized automated battery charging profile looks like this: http://tinyurl.com/k6xr9mk As a practical matter, there are variations on the theme that will produce a family of recharge profiles http://tinyurl.com/m3o6mtu Why would the charger charge at such a rate? Probably because it was conforming to design goals Why would a 12V battery test at 15.4 volts? Because you measured the voltage too soon. The REAL voltage representing state of charge can be measured only after the battery has been disconnected the charger for several hours. If the battery is healthy, something on the order of 12.8 to 13.0 volts for a fully charged open circuit value. Bob . . . ________________________________ Message 3 _____________________________________ Time: 04:26:04 AM PST US Subject: AeroElectric-List: Re: MIL SPEC spoof From: "racerjerry" > There is no > justification for the creation of a cadre' of > micro-czars to craft a specification for a successfully > marketed commodity whether it's a box of bolts or > a bag of brownies. Agreed Unless, of course, you are a bureaucrat trying to build your empire at hideous taxpayer expense. We dont have any of those, do we? -------- Jerry King Read this topic online here: http://forums.matronics.com/viewtopic.php?p=406033#406033 ________________________________ Message 4 _____________________________________ Time: 04:34:33 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Re: roll my own transponder antenna? At 09:23 AM 8/5/2013, you wrote: > >Well, that cheap TED xpdr antenna is backordered. I came up with a >few different lengths, googling. The diagram below shows it's ~2.5" >from the ground plane (aluminum skin). Also read on the sequair site >it would be 3.1", but that could be for a non-aluminum plane. > >http://www.seqair.com/skunkworks/Antennas/TpxAntProbs/TpxAntProbs.html There's a host of observed effects not all of which are significant. When you see an SWR plot like this . . . Emacs! all those peaks and valleys are artifacts of effects OTHER than the antenna itself. The plots achieved later Emacs! were MUCH smoother and had a a deep 'dip' toward 1:1 SWR at the frequency of interest. The article properly identifies the need for TIGHT electrical connection between the various components, preferably soldered. The 2.9" figure for overall length above the ground plane is fine. The article fails to mention that the 'resonant ground plane' has a radius equal to the height of the antenna or a diameter of 5.8". Alternatively you go with the non-resonant ground plane (like a belly skin) were exact dimensions are LARGE compared to 2.9" but operationally insignificant. The thing about every antenna needing to be tailored to an installation is bogus. Early transponders used a one-tube transmitter consisting of an pencil triode as an oscillator operating at a frequency controlled by a resonant cavity. Emacs! These transponders could be 'pulled' off-frequency by the effects of antennas. Modern, solid state transponders are not so afflicted. If you're building for a non-metalic airplane, 2.9" is the magic number for antenna length and radius of a ground plane. For a metal airplane, go for 2.9" antenna on an 'infinite' ground plane. In any case, metallic joints should be electrically 'tight' . . . solder is good. You can pick up one of these for about $20 shipping included. Emacs! http://tinyurl.com/lulfq5z You would mount this on a 2.9" radius disk for use in wood or plastic airplane. Bob . . . ________________________________ Message 5 _____________________________________ Time: 04:44:20 AM PST US From: "JOHN TIPTON" Subject: Re: AeroElectric-List: Re: roll my own transponder antenna? Would two units be a good idea, as a 'dipole' - one to ground (sleeve) lead ----- Original Message ----- From: Robert L. Nuckolls, III To: aeroelectric-list@matronics.com Sent: Tuesday, August 06, 2013 12:33 PM Subject: Re: AeroElectric-List: Re: roll my own transponder antenna? At 09:23 AM 8/5/2013, you wrote: Well, that cheap TED xpdr antenna is backordered. I came up with a few different lengths, googling. The diagram below shows it's ~2.5" from the ground plane (aluminum skin). Also read on the sequair site it would be 3.1", but that could be for a non-aluminum plane. http://www.seqair.com/skunkworks/Antennas/TpxAntProbs/TpxAntProbs.html There's a host of observed effects not all of which are significant. When you see an SWR plot like this . . . all those peaks and valleys are artifacts of effects OTHER than the antenna itself. The plots achieved later were MUCH smoother and had a a deep 'dip' toward 1:1 SWR at the frequency of interest. The article properly identifies the need for TIGHT electrical connection between the various components, preferably soldered. The 2.9" figure for overall length above the ground plane is fine. The article fails to mention that the 'resonant ground plane' has a radius equal to the height of the antenna or a diameter of 5.8". Alternatively you go with the non-resonant ground plane (like a belly skin) were exact dimensions are LARGE compared to 2.9" but operationally insignificant. The thing about every antenna needing to be tailored to an installation is bogus. Early transponders used a one-tube transmitter consisting of an pencil triode as an oscillator operating at a frequency controlled by a resonant cavity. These transponders could be 'pulled' off-frequency by the effects of antennas. Modern, solid state transponders are not so afflicted. If you're building for a non-metalic airplane, 2.9" is the magic number for antenna length and radius of a ground plane. For a metal airplane, go for 2.9" antenna on an 'infinite' ground plane. In any case, metallic joints should be electrically 'tight' . . . solder is good. You can pick up one of these for about $20 shipping included. http://tinyurl.com/lulfq5z You would mount this on a 2.9" radius disk for use in wood or plastic airplane. Bob . . . ________________________________ Message 6 _____________________________________ Time: 05:01:57 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Re: roll my own transponder antenna? At 06:43 AM 8/6/2013, you wrote: >Would two units be a good idea, as a 'dipole' - one to ground (sleeve) lead Sure, it's been done. http://tinyurl.com/n5ac7zt this antenna has limited applicability in wood/plastic airplanes only and mounted on the side of the fuselage. Check out the SWR plot. Transponder (TPX)/DME Antenna, for Composite Aircraft The large area, small aspect ratio antenna elements account for the broad-band performance. Bob . . . ________________________________ Message 7 _____________________________________ Time: 06:54:42 AM PST US From: Thomas Belvin Subject: AeroElectric-List: Invitation to connect on LinkedIn LinkedIn ------------ I'd like to add you to my professional network on LinkedIn. - Thomas Thomas Belvin Independent Machinery Professional Raleigh-Durham, North Carolina Area Confirm that you know Thomas Belvin: https://www.linkedin.com/e/-7hsi75-hk164s91-15/isd/15572319604/rubPRldA/?hs=false&tok=18ffedlkgxUBQ1 -- You are receiving Invitation to Connect emails. Click to unsubscribe: http://www.linkedin.com/e/-7hsi75-hk164s91-15/5JpN31bMiEhgKj2P554BMKMjiE_sJhkc5ikNWCs302Q4E2BJJJbUapQc/goo/aeroelectric-list-digest%40matronics%2Ecom/20061/I5182482300_1/?hs=false&tok=0ozMKQDBMxUBQ1 (c) 2012 LinkedIn Corporation. 2029 Stierlin Ct, Mountain View, CA 94043, USA. ________________________________ Message 8 _____________________________________ Time: 07:15:04 AM PST US Subject: AeroElectric-List: Re: MIL SPEC spoof From: "Eric M. Jones" > This is true, but on the other hand, who needs a 100 page Brownie > spec generously sprinkled with references to other regulations on every > page, to the point that a "Philadelphia Lawyer" has a problem with > interpretation. > > The proliferation of rules and regulations only speeds the growth of government and encourages the decline of personal honesty and integrity. Roger do not archive The entire document is only 23 pages, not 100, which includes the specification for the packaging and a page which you can submit to improve the specification. A jewel of brevity and conciseness. You can't include the accessory documents in your condemnation unless you plan to go into those other businesses too. People who think this spells the end of civilization need to get a life! If I were ordering fifty-million brownies for the troops, I would damned sure refer to this document and use it. For those of you who think a promise, a handshake, a smile, and a salute to the flag would get the job done...Let us know how that works out for you. Most engineers and business people understand that a blueprint or an order comprises a legal document; That's why there's a signature on it. Hey! I'd love to live in a world where "personal honesty and integrity" rule and everyone delivers precisely what I want, but even without guile, a description of exactly what I require can be longer than you might like. I don't do so much paperwork now, and a lot of that is in cyberspace, but in my working career I delivered 90-page change orders, and electrical approval documents that had to be wheeled in. We live in a complicated world. Don't get so upset. In WWII when GM took over the production of Wright-Cyclone motors, the GM engineers made over 10,000 changes in one month...all done by hand. -------- Eric M. Jones www.PerihelionDesign.com 113 Brentwood Drive Southbridge, MA 01550 (508) 764-2072 emjones(at)charter.net Read this topic online here: http://forums.matronics.com/viewtopic.php?p=406045#406045 ________________________________ Message 9 _____________________________________ Time: 07:38:30 AM PST US Subject: Re: AeroElectric-List: Battery question From: Richard Girard Thanks All, This was my first go 'round with a smart charger. Always good to learn something. Rick do not archive On Mon, Aug 5, 2013 at 10:10 PM, Richard Girard wrote: > My understanding is that it takes at least 13.8 volts to charge a 12 volt > battery. > Last Sunday I was using a Schumacher SC 8010A to charge a 12 volt 20 a.h. > AGM battery. The charger started out at 12.5 volts and gradually climbed > until after an hour the display was reading 15.5 volts. I disconnected the > charger even though when I selected percent of charge it indicated 71 % > charged. I used a Fluke VOM to check the battery and it indicated 15.4 > volts. The battery was not even warm to the touch so I put the charger back > on and continued charging until the battery was at 95% charge at which time > the charger was still at 15.5 volts. The battery was barely warm to the > touch. Again, with battery disconnected from the charger it tested at 15.4 > volts. The battery seemed to work normally when we attempted to start the > engine. > Why would the charger charge at such a rate? > Why would a 12V battery test at 15.4 volts? > > Rick Girard > > It isn't necessary to have relatives in Kansas City in order to be unhappy. > - Groucho Marx > > * > > * > > -- Zulu Delta Mk IIIC Thanks, Homer GBYM It isn't necessary to have relatives in Kansas City in order to be unhappy. - Groucho Marx ________________________________ Message 10 ____________________________________ Time: 08:22:00 AM PST US From: Dave Saylor Subject: Re: AeroElectric-List: Battery question Bob, can you comment on Odyssey's requirement to keep the charge below 15 volts? See page 6: http://www.odysseybattery.com/documents/US-ODY-OM-011_0213.pdf This requirement has also been given to me by phone on a few occasions. My understanding is that the battery has to see some extended time above 15 volts to cause any ill effects, particularly off-gassing. Does the SC 8010A drop below 15 quickly enough to avoid off-gassing, or would it be considered inappropriate for Odyssey batteries? Dave Saylor 831-750-0284 CL ________________________________ Message 11 ____________________________________ Time: 11:03:07 AM PST US Subject: Re: AeroElectric-List: Re: roll my own transponder antenna? From: DeWitt Whittington Bob, We've mounted the Bob Archer transponder antenna you picture just aft of Bulkhead B on the right side of the fuselage in our Sportsman 2+2. We haven't flown yet (gosh, going on 9 1/2 years of building) but we hope it works well. If we buckle down first flight will be this fall. Dee N18TA reserved DeWitt (Dee) Whittington 804-677-4849 iPhone 804-358-4333 Home www.VirginiaFlyIn.org Building Glasair Sportsman with 3 partners On Tue, Aug 6, 2013 at 8:00 AM, Robert L. Nuckolls, III < nuckolls.bob@aeroelectric.com> wrote: > At 06:43 AM 8/6/2013, you wrote: > > Would two units be a good idea, as a 'dipole' - one to ground (sleeve) lead > > > Sure, it's been done. > > http://tinyurl.com/n5ac7zt > > > this antenna has limited applicability in > wood/plastic airplanes only and mounted > on the side of the fuselage. Check out > the SWR plot. > > > [image: Transponder (TPX)/DME Antenna, for Composite Aircraft] > The large area, small aspect ratio antenna elements > account for the broad-band performance. > > > ** > > ** Bob . . . > > * > > * > > ________________________________ Message 12 ____________________________________ Time: 12:36:17 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: roll my own transponder antenna? At 10:33 PM 8/4/2013, you wrote: > >Hey :-) > >I rolled my own comm antenna a couple years ago. Antenna worked >okay, but the location caused RFI, so I bought one and mounted it in >a different location. This homemade com antenna could be cut down >and used for my transponder antenna. > >But, how long do I cut it? Also heard about not being able to check >swr in the xpdr freq range, so if I mess up, it could ruin my unit. >ACS sells the antenna for $18, so if there's any doubt, I'd go that way. A comm antenna design is generally more robust at the base to accommodate the wind and vibration loads of the larger antenna. Further, the value of keeping VERY short leads outside the coax world is not so critical. Unless you can measure and trim for low VSWR in your modified antenna, there is risk of failing to meet design goals. Bob . . . ________________________________ Message 13 ____________________________________ Time: 01:39:21 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Re: MIL SPEC spoof The entire document is only 23 pages, not 100, which includes the specification for the packaging and a page which you can submit to improve the specification. A jewel of brevity and conciseness. You can't include the accessory documents in your condemnation unless you plan to go into those other businesses too. You missed/ignored points offered that spoke to the necessity for citing the applicable paragraphs for a referenced document. It's lazy and economically hazardous writing to simply throw a bevy of reference specs into a purchase requirement. You end up with a package that nobody can hope to comply with . . . and if they did, the cost of your brownies would have a multiplier for the support of useless labor. People who think this spells the end of civilization need to get a life! If I were ordering fifty-million brownies for the troops, I would damned sure refer to this document and use it. For those of you who think a promise, a handshake, a smile, and a salute to the flag would get the job done...Let us know how that works out for you. What evidence have you seen demonstrating that the honorable supplier to a purchase requirement performs any better when every detail of the task is listed in black and white? The flip side of the coin asks, what evidence supports the notion that a dishonorable supplier's behaviors will become golden for having pledged to deliver to a constellation of micro-managing documents? Compare the Eggenfellner engine experience and Bede airplanes with say Van's, Zodiac, and other honorable contemporaries. I submit that Jan and Jim would have been no more successful had they been marching to a "brownie spec" nor did the efforts of Dick and Chris suffer for lack of such documents. Most engineers and business people understand that a blueprint or an order comprises a legal document; That's why there's a signature on it. Hey! I'd love to live in a world where "personal honesty and integrity" rule and everyone delivers precisely what I want, but even without guile, a description of exactly what I require can be longer than you might like. There's a difference between a "guide" (what I've called design goals) and the vague, intrusive, constricting imperatives administrated by individuals who haven't got a clue. Yes, your design goals should describe the intended purchase to the extent that it defines outcome. Would you dump "brownie spec" style requirements on your neurosurgeon . . . or does it suffice to compare his demonstrated track record with your desired outcome and shake hands over an agreement to accept the best he knows how to do for the purposes of mitigating your problem? I don't do so much paperwork now, and a lot of that is in cyberspace, but in my working career I delivered 90-page change orders, and electrical approval documents that had to be wheeled in. We live in a complicated world. Don't get so upset. Who's upset? I think most of this discussion has been a cooly calculated, simple recitation of facts and observable cause-effect pairs. In WWII when GM took over the production of Wright-Cyclone motors, the GM engineers made over 10,000 changes in one month...all done by hand. I think it was Chrysler-Dodge that took on the task but you've made my point. Were any company charged with sorting out the same problems with that engine design today, the spontaneous order successes of competent individuals would not be allowed to do what they do best. The war would be over before the engine became weapon-worthy. We would flog ourselves to defeat with our own specs. 150 years ago de Tocqueville wrote: "After having thus taken each individual one by one into its powerful hands, and having molded him as it pleases, the sovereign power extends its arms over the entire society; it covers the surface of society with a network of small, complicated, minute, and uniform rules, which the most original minds and the most vigorous souls cannot break through to go beyond the crowd; it does not break wills, but it softens them, bends them and directs them; it rarely forces action, but it constantly opposes your acting; it does not destroy, it prevents birth; it does not tyrannize, it hinders, it represses, it enervates, it extinguishes, it stupifies, and finally it reduces each nation to being nothing more than a flock of timid and industrious animals, of which the government is the shepherd." We've watched it happen in aviation. The phenomenon now touches everything we buy with ever increasing weight. The only sector of the labor market that has zero unemployment in the United States is civil service and that job market grows daily. Millions of no-value-added administrative-state public-servants (there's an oxymoron!) preside over brownie specs and hundreds of thousands of documents like it. It's de Tocqueville's hypothesis in action. All it will take ia a high profile 'incident' in OBAM aviation to bring de Tocqueville's hypothesis to our workshops, hangars and airplanes orchestrated by FAA, DEA, DHS, ATF, EPA . . . or probably all of them. I see no trends that argue with that hypothesis. Perhaps you can enlighten me? do not archive Bob . . . ________________________________ Message 14 ____________________________________ Time: 01:50:34 PM PST US From: Holger Selover-Stephan Subject: Re: AeroElectric-List: Navman Fuel Flow Meter Hi Joel, When searching for a metal housing transducer, have you looked at the 'Red Cube': http://www.aircraftspruce.com/catalog/inpages/eift60.php ? Oh, the price went down $10! Anyway, it's what some of the RV crowd is using. If you go to http://www.vansairforce.com , there are lots of discussions around it in the forum. Here's a thread that discusses the best installation location: http://www.supercub.org/forum/showthread.php?34031-fuel-flow-sensor-installation . The technical documentation says no additional pressure drop with blocked rotor. Buddy has the FlowScan 201A-6: http://www.aircraftspruce.com/catalog/inpages/mglfuelflowsensor.php installed and is happy with it. When I asked about a blocked rotor he said there is an increased pressure drop, but minimal and not affecting operations, at least on the paper. Holger On 7/31/13 3:52 PM, Joel Ventura wrote: > > > This is a post I made on one of the canard lists a couple months ago. > I got no response > there, so I thought someone here might have some information. First a > little background. > A member of that canard list posted a Navman fuel flow meter for sale > on the list, > and a well respected member of that list condemned the use of that > flow meter in aircraft > because it uses a plastic housing in its flow transducer, and at least > one pilot was killed > when that housing failed, feeding large amounts of fuel to an inflight > fire. > > ======================================================= > > First I want to thank Marc for his strong condemnation of the Navman > Fuel Flow Meter. .. ________________________________ Message 15 ____________________________________ Time: 01:58:37 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Battery question At 10:20 AM 8/6/2013, you wrote: >Bob, can you comment on Odyssey's requirement to >keep the charge below 15 volts? =C2 See page 6: > >http://www. odysseybattery.com/documents/US-ODY-OM-011_0213.pdf > >This requirement has also been given to me by phone on a few occasions. > >My understanding is that the battery has to see >some extended time above 15 volts to cause any >ill effects, particularly off-gassing. Does the=C2 >SC 8010A drop below 15 quickly enough to avoid >off-gassing, or would it be considered inappropriate for Odyssey batteries? > >Dave Saylor >831-750-0284 CL Have no idea my friend. Haven't tested it. Here's a chance for you to make a mark in the understanding of the various batteries and their accessories. If you acquired this (or something like it) http://tinyurl.com/lv2d6r4 you could hook your charger to a run-down battery and plot the recharge curve. I think I have an idea for how this critter could also watch the recharge current curve as well. The DAS would let you do data gathering in flight tests too. With respect to Odyssy's user data, I don't know why they would be any more vulnerable to service life degradation due to top-off protocols than any other manufacturer. ALL of them would like to see their recharge cycles stay at or below 15 volts . . . In fact, I've been disappointed that Schumacher hasn't upgraded their charger designs to do the idealize profile with a top-off to be pegged at 14.8 volts and held until charge current drops to 100 mA. If you deep cycled your Odyssey battery and hit it every time with the "too hot" Schumacher charger every time, I think the deep cycle treatment would be harder on the battery than the aggressive top-off. Under ideal conditions, a ship's battery NEVER sees a recharge from deep discharge so top-off protocols become moot. The few times that accident or circumstance demands a hot top-off shouldn't be a big event in the battery's service life. But it would be very interesting to know how that charger behaves when paired with your particular battery. If top-off plateau is higher than specified, then the time required for the recharge current to fall below the sustain decision point will be stretched out . . . wonder by how much? Bob . . . ________________________________ Message 16 ____________________________________ Time: 02:32:37 PM PST US From: Charlie England Subject: Re: AeroElectric-List: Navman Fuel Flow Meter I certainly wouldn't run a plastic transducer on the pressurized side on a fuel injected engine, but not all things plastic are always bad (as you apparently know, if you're posting on the canard list). The plastic transducers are typically used in both off-road vehicles and boats. They seem to survive in marine environments, which are just as hostile as a/c, and almost as dangerous. Running one on the cool side of the firewall on a carb'd engine is worth looking at. There are several other brands of marine fuel flow meters that have seen successful use in a/c. (I've been running a Lowrance model in an RV-4 for years.) Charlie On 08/06/2013 03:50 PM, Holger Selover-Stephan wrote: > Hi Joel, > > When searching for a metal housing transducer, have you looked at the > 'Red Cube': http://www.aircraftspruce.com/catalog/inpages/eift60.php ? > Oh, the price went down $10! Anyway, it's what some of the RV crowd is > using. If you go to http://www.vansairforce.com , there are lots of > discussions around it in the forum. Here's a thread that discusses the > best installation location: > http://www.supercub.org/forum/showthread.php?34031-fuel-flow-sensor-installation > . The technical documentation says no additional pressure drop with > blocked rotor. > > Buddy has the FlowScan 201A-6: > http://www.aircraftspruce.com/catalog/inpages/mglfuelflowsensor.php > installed and is happy with it. When I asked about a blocked rotor he > said there is an increased pressure drop, but minimal and not > affecting operations, at least on the paper. > > Holger > > > On 7/31/13 3:52 PM, Joel Ventura wrote: >> >> >> This is a post I made on one of the canard lists a couple months >> ago. I got no response >> there, so I thought someone here might have some information. First a >> little background. >> A member of that canard list posted a Navman fuel flow meter for sale >> on the list, >> and a well respected member of that list condemned the use of that >> flow meter in aircraft >> because it uses a plastic housing in its flow transducer, and at >> least one pilot was killed >> when that housing failed, feeding large amounts of fuel to an >> inflight fire. >> >> ======================================================= >> >> First I want to thank Marc for his strong condemnation of the Navman >> Fuel Flow Meter. .. > ________________________________ Message 17 ____________________________________ Time: 03:15:28 PM PST US Subject: AeroElectric-List: Re: roll my own transponder antenna? From: "messydeer" Thanks, Bob :-) I bought one of those $20 ones off ebay yesterday. If I get antsy, get my xpdr installed and want it tested for mode C before it arrives in the mail, I'll cut down my homebuilt antenna to 2.9". -------- Dan Read this topic online here: http://forums.matronics.com/viewtopic.php?p=406092#406092 ________________________________ Message 18 ____________________________________ Time: 03:44:40 PM PST US Subject: Re: AeroElectric-List: Re: roll my own transponder antenna? From: Tim Andres I probably missed part of the discussion but why are we trying to home brew a transponder antenna when you can buy one for $20? ACS or Steinair both sell one that works great. http://www.steinair.com/stor e.cfm?tlcatid=45 Tim Sent from my iPad On Aug 6, 2013, at 3:15 PM, "messydeer" wrote: > > Thanks, Bob :-) > > I bought one of those $20 ones off ebay yesterday. If I get antsy, get my x pdr installed and want it tested for mode C before it arrives in the mail, I 'll cut down my homebuilt antenna to 2.9". > > -------- > Dan > > > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=406092#406092 > > > > > > > ========================== ========= ========================== ========= ========================== ========= ========================== ========= > > > ________________________________ Message 19 ____________________________________ Time: 05:43:34 PM PST US From: Kelly McMullen Subject: Re: AeroElectric-List: Navman Fuel Flow Meter The transducer he suggested is not "plastic". It probably does have a plastic turbine wheel inside, but it is the certified fuel flow transducer from Electronics International with all metal case. On 8/6/2013 2:31 PM, Charlie England wrote: > I certainly wouldn't run a plastic transducer on the pressurized side > on a fuel injected engine, but not all things plastic are always bad > (as you apparently know, if you're posting on the canard list). The > plastic transducers are typically used in both off-road vehicles and > boats. They seem to survive in marine environments, which are just as > hostile as a/c, and almost as dangerous. Running one on the cool side > of the firewall on a carb'd engine is worth looking at. There are > several other brands of marine fuel flow meters that have seen > successful use in a/c. (I've been running a Lowrance model in an RV-4 > for years.) > > Charlie > > > On 08/06/2013 03:50 PM, Holger Selover-Stephan wrote: >> Hi Joel, >> >> When searching for a metal housing transducer, have you looked at the >> 'Red Cube': http://www.aircraftspruce.com/catalog/inpages/eift60.php >> ? Oh, the price went down $10! Anyway, it's what some of the RV crowd >> is using. If you go to http://www.vansairforce.com , there are lots >> of discussions around it in the forum. Here's a thread that discusses >> the best installation location: >> http://www.supercub.org/forum/showthread.php?34031-fuel-flow-sensor-installation >> . The technical documentation says no additional pressure drop with >> blocked rotor. >> >> Buddy has the FlowScan 201A-6: >> http://www.aircraftspruce.com/catalog/inpages/mglfuelflowsensor.php >> installed and is happy with it. When I asked about a blocked rotor he >> said there is an increased pressure drop, but minimal and not >> affecting operations, at least on the paper. >> >> Holger >> >> >> On 7/31/13 3:52 PM, Joel Ventura wrote: >>> >>> >>> This is a post I made on one of the canard lists a couple months >>> ago. I got no response >>> there, so I thought someone here might have some information. First >>> a little background. >>> A member of that canard list posted a Navman fuel flow meter for >>> sale on the list, >>> and a well respected member of that list condemned the use of that >>> flow meter in aircraft >>> because it uses a plastic housing in its flow transducer, and at >>> least one pilot was killed >>> when that housing failed, feeding large amounts of fuel to an >>> inflight fire. >>> >>> ======================================================= >>> >>> First I want to thank Marc for his strong condemnation of the Navman >>> Fuel Flow Meter. .. >> > > * > > > * ________________________________ Message 20 ____________________________________ Time: 06:07:46 PM PST US Subject: Re: AeroElectric-List: Navman Fuel Flow Meter From: Ron Walker On Tue, 2013-08-06 at 17:41 -0700, Kelly McMullen wrote: > > > The transducer he suggested is not "plastic". I think Charlie was referring to the OP discussing the "Navman Fuel Flow Meter" ... which is certainly plastic. I've been running one in my RV7a for 10 yrs (carbureted O-360) without incident. I had to re-read a few posts to understand that myself, since I agree that the red cube is certainly not plastic, and is what I'm using in my 10. --Ron ________________________________ Message 21 ____________________________________ Time: 06:53:26 PM PST US Subject: Re: AeroElectric-List: Navman Fuel Flow Meter From: Tim Andres This may be of interest to those running a Navman flow sensor. No horse in this race, but its worth reading I think. http://www.cozybuilders.org/Glenn_Saunders/Complete_Report.pdf Tim Sent from my iPad On Aug 6, 2013, at 6:07 PM, Ron Walker wrote: > > On Tue, 2013-08-06 at 17:41 -0700, Kelly McMullen wrote: >> >> >> The transducer he suggested is not "plastic". > > I think Charlie was referring to the OP discussing the "Navman Fuel Flow > Meter" ... which is certainly plastic. I've been running one in my RV7a > for 10 yrs (carbureted O-360) without incident. I had to re-read a few > posts to understand that myself, since I agree that the red cube is > certainly not plastic, and is what I'm using in my 10. > > --Ron > > > > > > ________________________________ Message 22 ____________________________________ Time: 08:35:10 PM PST US Subject: AeroElectric-List: Re: roll my own transponder antenna? From: "messydeer" I'm disappointed to report that I couldn't solder the coax to the adapter fitting. I got the core soldered okay, but the braid stumped me. Solder would stick to the braid, but not the fitting. Think it's such a big heat sink. I was afraid to hold the iron on the braid too long for fear of melting the insulation. But I guess if it's not hot enough for the solder to stick to the fitting, it's not going to melt the plastic? -------- Dan Read this topic online here: http://forums.matronics.com/viewtopic.php?p=406115#406115 ------------------------------------------------------------------------------------- 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.