---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Wed 10/16/13: 14 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 05:12 AM - Re: Re: Copper Foil width for VOR antenna (Fisher Paul A.) 2. 09:37 AM - Re: EXP 2 Bus workaround (Robert L. Nuckolls, III) 3. 10:09 AM - Re: Relay for Critical Power Feed (Thomas E Blejwas) 4. 10:56 AM - Re: Relay for Critical Power Feed (Eric M. Jones) 5. 12:01 PM - Re: New electrical architecture with ENGINE BUS (Sacha) 6. 01:04 PM - Re: EXP 2 Bus workaround (Fred Klein) 7. 03:49 PM - Re: EXP 2 Bus workaround (Robert L. Nuckolls, III) 8. 03:49 PM - Re: New electrical architecture with ENGINE BUS (Robert L. Nuckolls, III) 9. 04:36 PM - Re: Copper Foil width for VOR antenna (p32gxy) 10. 05:32 PM - Re: New electrical architecture with ENGINE BUS (user9253) 11. 05:38 PM - Re: Re: Copper Foil width for VOR antenna (rayj) 12. 08:17 PM - Re: Copper Foil width for VOR antenna (p32gxy) 13. 09:03 PM - Re: Re: Copper Foil width for VOR antenna (rayj) 14. 10:49 PM - Re: New electrical architecture with ENGINE BUS (Sacha) ________________________________ Message 1 _____________________________________ Time: 05:12:36 AM PST US From: "Fisher Paul A." Subject: RE: AeroElectric-List: Re: Copper Foil width for VOR antenna Just another data point. I used Mr. Weir's antennas in my Q-200 (fully composite structure). The vertically polarized comm antenna in the tail and the horizontally polarized VOR antenna in the main wing. Both were installed exactly as Mr. Weir describes using his kit including the copper foil. Both antennas have given satisfactory performance for 23+ years and ~1,500 flight hours. Paul A. Fisher Q-200 N17PF -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Robert L. Nuckolls, III Sent: Tuesday, October 15, 2013 10:10 PM Subject: Re: AeroElectric-List: Re: Copper Foil width for VOR antenna --> At 04:26 PM 10/15/2013, you wrote: > >Thx... I am actually thinking of using the braid only as the antenna >material... as part of making a proper balun one would only use the >braid to connect to the antenna elements anyway while the center >cnnductor is not connected... this should avoid the problem you are >describing... as long as i can successfully slide about a 16" long >undisturbed braid-external shielding up on the stripped coax to avoid >the large resulting gap. > >Water will not get into this setup as it will be saturated with epoxy. The problem with embedded antennas is the potential for fatigue failure of the conductors if the composite structure flexes. This can produce hairline fractures in foil or wire antennas bonded to a composite surface. It can make your antenna conductors look like the wires in a strain guage . . . that stretch and compress as the surface responds to structure flexing. RF bandwidth of the wider foil is attractive but as mentioned here, insignificant with respect to performance. Consider an ALL COAX antenna assembly. Balun is optional . . . cool but performance difference is very small. Making the antenna elements from coax braid FLOATING INSIDE a piece of 1/4" Nylon tubing will get you a simple antenna material, adequate performance and the tubing isolates the antenna from structure so that flexing doesn't mechanically irritate the elements. Bob . . . ________________________________ Message 2 _____________________________________ Time: 09:37:29 AM PST US From: "Robert L. Nuckolls, III" Subject: RE: AeroElectric-List: EXP 2 Bus workaround At 09:51 PM 10/15/2013, you wrote: >Bob, >A friend of mine is running a Mazda engine on a test stand and is >using a lot of the same controller, injectors, coils, etc that Fred >is using. I asked him for some amperage load information and this >is what he measured on his running engine: > >"I went out and measured the current requirements of the various >systems on my Renesis test stand which has an EC2 and GM D585 >ignition coils. System voltage was 15V with a battery charger >attached and the CAS was driven to be equivalent to an engine RPM of >5000. When the EC2 is powered up, there are also a tach, 2 VDO >temperature gauges, an O2 gauge, a voltmeter, and an electronic fuel >pressure gauge powered as well. > >The results for the individual systems are: >EC2 and gauges: 0.8 A >2 leading coils: 2.4 A >2 trailing coils: 2.4 A >2 primary injectors 0.7 A >2 secondary injectors: 0.7 A >1 Mazda stock RX7 fuel pump: 3.8 A > >Total in normal running config: 10.8 A > >The fuel pumps that RWS sold draw very close to the same current >that the Mazda one does." > >This hopefully will shed some light on the load that Fred will be >experiencing on his engine Aha! Numbers! Thank you for taking the time to go measure. Are these numbers RPM dependent? Another constellation of values at 4000 would be very interesting. I am reminded of a remark by Lord Kelvin who said . . . "In physical science a first essential step in the direction of learning any subject is to find principles of numerical reckoning and practicable methods for measuring some quality connected with it. I often say that when you can measure what you are speaking about, and express it in numbers, you know something about it; but when you cannot measure it, when you cannot express it in numbers, your knowledge is of a meagre and unsatisfactory kind; it may be the beginning of knowledge, but you have scarcely in your thoughts advanced to the stage of science, whatever the matter may be." Okay, how would numbers like this (remember, these are exemplar, i.e. similar numbers) drive the thought processes for architecture for Fred's airplane with an EXP=Bus installed? The real numbers for Fred's engine may not be available until he can run the engine. Bill's numbers do give reason to believe that Fred's Plan-B design goals may not be so limited as originally thought. With two, PC-680 batteries on board, Fred's airplane carries 32 a.h. of capacity at a 20 hr rate when new. Consulting the discharge curves for a PC680 we see . . . Emacs! Assuming Fred's real engine demands are on the order of 10A, then a new PC680 will sustain flight for about 1.2 hrs. Running BOTH batteries in parallel would load each battery to the tune of 5A for an endurance of 2.7 hours. Hmmmm . . . this gives us numbers for consideration that might lead to a design that eliminates the word "emergency" from the description of an alternator failure event. This line of reasoning becomes more focused when we get real numbers from the folks who manufactured Fred's engine but the process is moving in the right direction. Bob . . . ________________________________ Message 3 _____________________________________ Time: 10:09:55 AM PST US Subject: Re: AeroElectric-List: Relay for Critical Power Feed From: Thomas E Blejwas Thanks Eric. I was also missing the inherent redundancy in the bridge diode. If the diode through which current is flowing fails, switching to the other power source (if it isn't already on) restores current. The two buses might be connected, but that would not prevent power to the critical component. I will save the relay arrangement I described for switching between my fuel pumps. If both are inadvertently energized, the pressure will exceed the capabilities of my fuel regulator. The relay arrangement will prevent that. Tom Sent from my iPad ________________________________ Message 4 _____________________________________ Time: 10:56:19 AM PST US Subject: AeroElectric-List: Re: Relay for Critical Power Feed From: "Eric M. Jones" I claim this is a better way to go and have sold lots of these to Aeroelectric builders doing Z-19 http://www.periheliondesign.com/powerschottkydiodes.htm -------- 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=410702#410702 ________________________________ Message 5 _____________________________________ Time: 12:01:24 PM PST US Subject: Re: AeroElectric-List: New electrical architecture with ENGINE BUS From: Sacha >> can you remind >> me what software you use to produce such drawings? > > TurboCAD > NanoCAD > DraftSight Joe/Jan/Bob Thank you. I've downloaded nanoCAD and will give it a try. I'm planning on using it to produce a diagram of the wiring on my Kitfox (which did not originate from a very carefully thought out plan) and then presenting it to the list to for advice on modifying it. Sacha ________________________________ Message 6 _____________________________________ Time: 01:04:58 PM PST US From: Fred Klein Subject: Re: AeroElectric-List: EXP 2 Bus workaround On Oct 16, 2013, at 9:25 AM, Robert L. Nuckolls, III wrote: > This line of reasoning becomes more focused when we > get real numbers from the folks who manufactured Fred's > engine but the process is moving in the right direction. Bob...I cannot get any additional data from my engine guy w/ regard to the electrical power draw at cruise rpm (or for any other rpm for that matter) unless something can be gleaned from a video of the dyno readout: http://www.youtube.com/watch?v=epgQaA4SXe8 ...frankly, I can't read a thing from the out of focus monitor... Fred ________________________________ Message 7 _____________________________________ Time: 03:49:36 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: EXP 2 Bus workaround At 02:48 PM 10/16/2013, you wrote: >On Oct 16, 2013, at 9:25 AM, Robert L. Nuckolls, III wrote: > >> This line of reasoning becomes more focused when we >> get real numbers from the folks who manufactured Fred's >> engine but the process is moving in the right direction. > >Bob...I cannot get any additional data from my engine guy w/ regard >to the electrical power draw at cruise rpm (or for any other rpm for >that matter) unless something can be gleaned from a video of the dyno readout: > >http://www.youtube.com/watch?v=epgQaA4SXe8 > >...frankly, I can't read a thing from the out of focus monitor... > >Fred Which engine are we talking about? Is there no supplier support? Is there a user's forum of individuals who are already flying? Bob . . . ________________________________ Message 8 _____________________________________ Time: 03:49:53 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: New electrical architecture with ENGINE BUS At 01:48 PM 10/16/2013, you wrote: > > >> can you remind > >> me what software you use to produce such drawings? > > > > TurboCAD > > NanoCAD > > DraftSight > >Joe/Jan/Bob > >Thank you. I've downloaded nanoCAD and will give it a try. >I'm planning on using it to produce a diagram of the wiring on my >Kitfox (which did not originate from a very carefully thought out >plan) and then presenting it to the list to for advice on modifying it. >Sacha All of the z-figures are available in both pdf and dwg formats. NanoCAD will open, edit, print and save the .dwg drawings. So you can start with a almost-but-not-quite drawing and modify to meed your needs. Have you used a cad program of any kind before? Bob . . . ________________________________ Message 9 _____________________________________ Time: 04:36:58 PM PST US Subject: AeroElectric-List: Re: Copper Foil width for VOR antenna From: "p32gxy" I am loving the idea of a protective sheath/tube to achieve mechanical isolation... Unfortunately, i don't see how I can make use of this approach without either drilling holes in the spar or messing up the wing's shape/airflow The VOR antenna I can install has to be flat so that it integrates into the wing surface. Don't want to be compromising the wing skin... moving the antenna is also not an option because the only place I can keep the tips away from "metal" antennae like structures is in the outboard 1/3 of the wing. I am all open to suggestions and will consider anything and everything including novel designs and unusual shapes as I am finding that the 22.8" per leg of the V shaped antennae is hard to place without interference.... please keep them comming. Thx. nuckolls.bob(at)aeroelect wrote: > At 04:26 PM 10/15/2013, you wrote > The problem with embedded antennas is the potential for > fatigue failure of the conductors if the composite > structure flexes. This can produce hairline fractures > in foil or wire antennas bonded to a composite surface. It can > make your antenna conductors look like the wires in a strain > guage . . . that stretch and compress as the surface responds > to structure flexing. > > RF bandwidth of the wider foil is attractive but as mentioned > here, insignificant with respect to performance. Consider an > ALL COAX antenna assembly. Balun is optional . . . cool > but performance difference is very small. Making the > antenna elements from coax braid FLOATING INSIDE a piece of 1/4" > Nylon tubing will get you a simple antenna material, > adequate performance and the tubing isolates the antenna > from structure so that flexing doesn't mechanically irritate > the elements. > > > Bob . . . Read this topic online here: http://forums.matronics.com/viewtopic.php?p=410717#410717 ________________________________ Message 10 ____________________________________ Time: 05:32:09 PM PST US Subject: AeroElectric-List: Re: New electrical architecture with ENGINE BUS From: "user9253" I used one of those free CAD programs for awhile. When I went to view one of my drawings at a later date, I could not open it because the program license had expired after one year. It was necessary to register again to get another free license to use the program for one more year. What if I did not happen to have an internet connection? Or what if the company goes out of business? Then I would not be able to open my drawings. So I acquired TurboCAD. I can open my drawings whenever I want without depending on the internet or the software manufacturer. Joe -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=410719#410719 ________________________________ Message 11 ____________________________________ Time: 05:38:31 PM PST US From: rayj Subject: Re: AeroElectric-List: Re: Copper Foil width for VOR antenna A technique used by some boat builders to form pillow blocks for prop shafts is to coat the shaft with wax of sufficient thickness to assure clearance between the block and the shaft when the wax is removed. WARNING, I HAVE NOT TRIED THE TECHNIQUE DISCUSSED BELOW. IT IS ONLY SPECULATION!!!!! A similar approach might be applied to the copper strip in the matrix. Coat it with several layers of wax or mold release before imbeding it in the matrix. The theory is that the wax will prevent the matrix from bonding to the copper, effectively creating a space on either side of the copper allowing it to move slightly to avoid being stressed when the matrix is deformed. The downside is that it is functionally a delamination. Whether or not that is acceptable would have to be decided by the builder. Raymond Julian Kettle River, MN. "And you know that I could have me a million more friends, and all I'd have to lose is my point of view." - John Prine On 10/16/2013 06:27 PM, p32gxy wrote: > > I am loving the idea of a protective sheath/tube to achieve mechanical isolation... > Unfortunately, i don't see how I can make use of this approach without either drilling holes in the spar or messing up the wing's shape/airflow > > The VOR antenna I can install has to be flat so that it integrates into the wing surface. Don't want to be compromising the wing skin... moving the antenna is also not an option because the only place I can keep the tips away from "metal" antennae like structures is in the outboard 1/3 of the wing. > > I am all open to suggestions and will consider anything and everything including novel designs and unusual shapes as I am finding that the 22.8" per leg of the V shaped antennae is hard to place without interference.... please keep them comming. > > Thx. > > > nuckolls.bob(at)aeroelect wrote: >> At 04:26 PM 10/15/2013, you wrote >> The problem with embedded antennas is the potential for >> fatigue failure of the conductors if the composite >> structure flexes. This can produce hairline fractures >> in foil or wire antennas bonded to a composite surface. It can >> make your antenna conductors look like the wires in a strain >> guage . . . that stretch and compress as the surface responds >> to structure flexing. >> >> RF bandwidth of the wider foil is attractive but as mentioned >> here, insignificant with respect to performance. Consider an >> ALL COAX antenna assembly. Balun is optional . . . cool >> but performance difference is very small. Making the >> antenna elements from coax braid FLOATING INSIDE a piece of 1/4" >> Nylon tubing will get you a simple antenna material, >> adequate performance and the tubing isolates the antenna >> from structure so that flexing doesn't mechanically irritate >> the elements. >> >> >> Bob . . . > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=410717#410717 > > ________________________________ Message 12 ____________________________________ Time: 08:17:35 PM PST US Subject: AeroElectric-List: Re: Copper Foil width for VOR antenna From: "p32gxy" raymondj(at)frontiernet.n wrote: > A technique used by some boat builders to form pillow blocks for prop shafts is to coat the shaft with wax of sufficient thickness to assure clearance between the block and the shaft when the wax is removed.. > Well... I have been thinking of something similar... except using copper foils such as http://www.mcmaster.com/#9053k12/=oyvy3i and putting it between 2 layers of PTFE tape such as http://www.mcmaster.com/#76475a43/=oyw325 before covering the thing with 1 ply of 3oz glass. This approach, I think, would create a non-stick copper foil 'assembly' to which epoxy would not stick... effectively the copper tape would not be bound to the wing skin. The push-pull on the copper foil should be much reduced... The "de-lamination" should not be an issue as the covering fiberglass layer only has the purpose of keeping the tape in place... no structural impact as i understand it. The only place to be fixed would be where the coax attaches as the leads would have to penetrate the wing skin through very small holes. I don't mind spending a bit more money upfront rather than fixing broken VOR antennae later :-) Read this topic online here: http://forums.matronics.com/viewtopic.php?p=410726#410726 ________________________________ Message 13 ____________________________________ Time: 09:03:41 PM PST US From: rayj Subject: Re: AeroElectric-List: Re: Copper Foil width for VOR antenna The only potential problem I see with that is that the epoxy might be drawn in between the 2 pieces of plastic by capillary action or if it's vacuum bagged, and then bond to the copper. You might be able to get some thin wall HDPE tubing that will pull down flat if you vacuum bag it. I wonder if you could just put some grease on it. I suppose a couple of test layups will answer most of the questions. I just had another thought. Could you lay a thin piece of styrofoam in and then dissolve it and slide the foil in? Then just fill the slot, leaving the copper anchored at one end. Good luck, I look forward to hearing what your solution is. Raymond Julian Kettle River, MN. "And you know that I could have me a million more friends, and all I'd have to lose is my point of view." - John Prine On 10/16/2013 10:15 PM, p32gxy wrote: > > > raymondj(at)frontiernet.n wrote: >> A technique used by some boat builders to form pillow blocks for prop shafts is to coat the shaft with wax of sufficient thickness to assure clearance between the block and the shaft when the wax is removed.. >> > > > Well... I have been thinking of something similar... except using copper foils such as http://www.mcmaster.com/#9053k12/=oyvy3i and putting it between 2 layers of PTFE tape such as http://www.mcmaster.com/#76475a43/=oyw325 before covering the thing with 1 ply of 3oz glass. > > This approach, I think, would create a non-stick copper foil 'assembly' to which epoxy would not stick... effectively the copper tape would not be bound to the wing skin. The push-pull on the copper foil should be much reduced... > > The "de-lamination" should not be an issue as the covering fiberglass layer only has the purpose of keeping the tape in place... no structural impact as i understand it. > > The only place to be fixed would be where the coax attaches as the leads would have to penetrate the wing skin through very small holes. > > I don't mind spending a bit more money upfront rather than fixing broken VOR antennae later :-) > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=410726#410726 > > ________________________________ Message 14 ____________________________________ Time: 10:49:07 PM PST US Subject: Re: AeroElectric-List: New electrical architecture with ENGINE BUS From: Sacha >> NanoCAD will open, edit, print and save the .dwg drawings. So you can sta rt with a almost-but-not-quite drawing and modify to meed your needs. Thanks, I'll do that. I have to first figure out what my setup actually is. T he wiring was mostly five by a friend of mine who's been flying for 30+ year s and who built a few planes before, including one of his own designs. We discussed certain things like OV protection and the ability to turn the A lternator off (which he considered unnecessary on a Rotax 912 while using it s inbuilt generator, but which I insisted on) but I didn't make a note of al l the schematics at the time. I'll have to sit down and write it all out. >> Have you used a cad program of any kind before? No. I tried poking around last night and was able to open the Dwg files on t he aero electric site. It took me a while to figure out how to simply copy a nd paste items and then I had to scale them to make them fit what I had draw n... Seems like i might save done time with some decent training material. A re you aware of any? I'm considering buying TurboCAD but most of the stuff on ebay US doesn't shi p to Italy so it would be a bit convoluted to do so. It's so difficult to ge t hands on stuff here compared to the US where you can just order and get it overnight! > ------------------------------------------------------------------------------------- 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.