---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Sun 11/12/17: 11 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 02:01 AM - Re: Transponder antenna (Airdog77) 2. 07:00 AM - Simple EFIS backup battery wiring (Matt Stecher) 3. 01:26 PM - Re: Simple EFIS backup battery wiring (donjohnston) 4. 03:48 PM - Re: Simple EFIS backup battery wiring (user9253) 5. 04:04 PM - Re: Re: Simple EFIS backup battery wiring (Charlie England) 6. 04:56 PM - Re: z13/8 ess bus feed (Robert L. Nuckolls, III) 7. 05:02 PM - Re: Transponder antenna (donjohnston) 8. 05:32 PM - Re: Re: Transponder antenna (Charlie England) 9. 06:51 PM - Re: Transponder antenna (donjohnston) 10. 07:15 PM - Re: Re: Transponder antenna (Charlie England) 11. 07:15 PM - Re: Transponder antenna (Airdog77) ________________________________ Message 1 _____________________________________ Time: 02:01:50 AM PST US Subject: AeroElectric-List: Re: Transponder antenna From: "Airdog77" Mike, > In a composite aircraft does the transponder antenna have to be outside the fuselage? No, none of the antennas have to be outside the aircraft. > If it can be inside how do you make a ground plane? Check out the Advanced Aircraft Electronics L2 Transponder Antenna made specifically for composite aircraft, no ground plane required and costs less than $100. http://www.aircraftspruce.com/catalog/avpages/antennasystems1.php?clickkey=4083 > Is it OK to be close to the COM antenna? If you mean the transponder antenna, from my understanding no. I think you want to be as far away as possible, within reason. Different antennas may have different requirements. Cheers, Wade -------- Airdog Wade Parton Building Long-EZ N916WP www.longezpush.com Read this topic online here: http://forums.matronics.com/viewtopic.php?p=474854#474854 ________________________________ Message 2 _____________________________________ Time: 07:00:29 AM PST US From: Matt Stecher Subject: AeroElectric-List: Simple EFIS backup battery wiring I need to install a small battery on my MGS Extreme so that it can be kept up and running during engine start for my VFR 601XL.=C2-I would like to k eep the wiring as simple as possible, but also allow the 1.2 AH battery to be maintained by the alternator.=C2-MGL has an example that uses a diode and switch to power the backup pin on another system, but the Extreme does not include this.How has everyone else handled this?Thanks,Matt StecherSkyd ive Houston Airpark ________________________________ Message 3 _____________________________________ Time: 01:26:52 PM PST US Subject: AeroElectric-List: Re: Simple EFIS backup battery wiring From: "donjohnston" I have a GRT EFIS and here's how I did mine. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=474858#474858 Attachments: http://forums.matronics.com//files/backup_battery_331.jpg ________________________________ Message 4 _____________________________________ Time: 03:48:54 PM PST US Subject: AeroElectric-List: Re: Simple EFIS backup battery wiring From: "user9253" Here is a circuit similar to the above. A battery fuse and switch could be added if desired. -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=474860#474860 Attachments: http://forums.matronics.com//files/backup_battery_905.jpg ________________________________ Message 5 _____________________________________ Time: 04:04:30 PM PST US Subject: Re: AeroElectric-List: Re: Simple EFIS backup battery wiring From: Charlie England And if you want max voltage available in a simple circuit like that, Schottky diodes are pretty cheap now. Just search ebay for lots of options. Somewhat lower forward voltage drop than silicon. On 11/12/2017 5:48 PM, user9253 wrote: > > Here is a circuit similar to the above. A battery fuse and switch could be added if desired. > > -------- > Joe Gores --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ________________________________ Message 6 _____________________________________ Time: 04:56:32 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: z13/8 ess bus feed At 05:49 PM 11/11/2017, you wrote: > >Hi. Building an RV7 in the UK with a G3X system and thinking of >using the z13/8 architecture with the SD8 backup alt and GAD27 to >maintain voltage to the GDU etc during engine start. Is it normal or >acceptable to keep the essential bus alternate feed on during flight >in case of battery contactor failure? I'd rather not add a second battery. Battery contactors seldom fail in fight . . . I use the word 'seldom' because the rate is fanishingly small. I've never encountered such a failure. A contactor on the edge of failure will raise caution flags by causing fussy starts or failure to close during start up. Even if it does fail, you probably wouldn't know it until the next preflight. The airplane will continue to run on the self excited alternator. But if you want to fly around with the alternate feed switch closed, it doesn't hurt anything but it's unnecessary. Bob . . . ________________________________ Message 7 _____________________________________ Time: 05:02:42 PM PST US Subject: AeroElectric-List: Re: Transponder antenna From: "donjohnston" mike(at)vision499.com wrote: > In a composite aircraft does the transponder antenna have to be outside the fuselage? If your composite is fiberglass, it does not have to be on the outside. If it's carbon fiber, then you may have some issues. mike(at)vision499.com wrote: > > If it can be inside how do you make a ground plane? I used aluminum. Here's how I built mine. http://www.velocity-xl.com/blog/2013/11/07/13-99-transponder-antenna-ground-plane/ mike(at)vision499.com wrote: > Is it OK to be close to the COM antenna In a perfect world, they would be as far apart as possible. I'm sure there's a recommended minimum. But I don't know what that is. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=474866#474866 ________________________________ Message 8 _____________________________________ Time: 05:32:47 PM PST US Subject: Re: AeroElectric-List: Re: Transponder antenna From: Charlie England That design is great for those of us who are financially challenged; you can buy the little spike antenna for around $20. Add a bit of scrap aluminum & you're done. On 11/12/2017 7:02 PM, donjohnston wrote: > > > mike(at)vision499.com wrote: >> In a composite aircraft does the transponder antenna have to be outside the fuselage? > If your composite is fiberglass, it does not have to be on the outside. If it's carbon fiber, then you may have some issues. > > > mike(at)vision499.com wrote: >> If it can be inside how do you make a ground plane? > I used aluminum. Here's how I built mine. > http://www.velocity-xl.com/blog/2013/11/07/13-99-transponder-antenna-ground-plane/ > > > mike(at)vision499.com wrote: >> Is it OK to be close to the COM antenna > In a perfect world, they would be as far apart as possible. I'm sure there's a recommended minimum. But I don't know what that is. > --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ________________________________ Message 9 _____________________________________ Time: 06:51:22 PM PST US Subject: AeroElectric-List: Re: Transponder antenna From: "donjohnston" ceengland7(at)gmail.com wrote: > That design is great for those of us who are financially challenged; you > can buy the little spike antenna for around $20. Add a bit of scrap > aluminum & you're done. Not sure about the "financially challenged" comment. I didn't see the benefit to spending $100's on something that I could build for about $25. If that makes me "Financially challenged" then so be it. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=474871#474871 ________________________________ Message 10 ____________________________________ Time: 07:15:11 PM PST US Subject: Re: AeroElectric-List: Re: Transponder antenna From: Charlie England An earlier post mentioned a dipole for ~$100.00. The $20+aluminum scrap is the alternative for us 'financially challenged'. When I wrote 'That design', I was referring to the spike. On 11/12/2017 8:50 PM, donjohnston wrote: > > > ceengland7(at)gmail.com wrote: >> That design is great for those of us who are financially challenged; you >> can buy the little spike antenna for around $20. Add a bit of scrap >> aluminum & you're done. > > Not sure about the "financially challenged" comment. I didn't see the benefit to spending $100's on something that I could build for about $25. > > If that makes me "Financially challenged" then so be it. > --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ________________________________ Message 11 ____________________________________ Time: 07:15:44 PM PST US Subject: AeroElectric-List: Re: Transponder antenna From: "Airdog77" > If your composite is fiberglass, it does not have to be on the outside. If it's carbon fiber, then you may have some issues. Good point. I should have noted the carbon fiber caveat. I went the same way you did initially Don, and it is fairly easy and cost effective. But then after I ran across a few builders who used the L2, it solved my issue of finding a location for mounting the antenna, and also kept from having anything poking out (for us non-CF folks!). Cheers, Wade -------- Airdog Wade Parton Building Long-EZ N916WP www.longezpush.com Read this topic online here: http://forums.matronics.com/viewtopic.php?p=474872#474872 ------------------------------------------------------------------------------------- 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.