---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Fri 02/12/21: 6 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 05:20 AM - Re: I forgot how to list on the list (Robert L. Nuckolls, III) 2. 08:44 AM - Van's Aircraft Statement (user9253) 3. 09:18 AM - Re: Van's Aircraft Statement (C&K) 4. 10:44 AM - Re: Kitfox vertical fin antenna opportunities (Eric Page) 5. 10:57 AM - Re: Van's Aircraft Statement (Charlie England) 6. 01:03 PM - Repair of Apollo GX65 (Janet Amtmann) ________________________________ Message 1 _____________________________________ Time: 05:20:42 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: I forgot how to list on the list At 07:42 PM 2/11/2021, you wrote: >How do I list on the=C2 list.=C2 I do get the list in my emails. > >Jurgen Amtmann Just send your posting to "aeroelectric-list@matronics.com" with a new subject line. Everything sent to this address is echoed to all List members. Bob . . . Un impeachable logic: George Carlin asked, "If black boxes survive crashes, why don't they make the whole airplane out of that stuff?" ________________________________ Message 2 _____________________________________ Time: 08:44:11 AM PST US Subject: AeroElectric-List: Van's Aircraft Statement From: "user9253" Here is a quote from Van's Aircraft FLIGHT TRAINING SUPPLEMENT: https://www.vansaircraft.com/wp-content/uploads/2020/10/RV-12iS-FTS-4.pdf page 6-6 > The Rotax 912 iS is equipped with two voltage regulators, one for each generator on the engine. These regulators reject any unused electrical power as heat. Allowing the power usage to fall below 7 amps for extended periods of time may damage the regulators, especially on hot days. That can not be true can it? Suppose that 21 amps are available but not used by the aircraft electrical system. 21 amps x 14 volts = 300 watts of heat that must be dissipated by the voltage regulators. Don't modern permanent magnet voltage regulators work by shutting off the output during part of the AC cycle using SCRs that are in series with the output? -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=500656#500656 ________________________________ Message 3 _____________________________________ Time: 09:18:50 AM PST US Subject: Re: AeroElectric-List: Van's Aircraft Statement From: C&K Pretty sure I've read all of the current rotax manuals and bulletins for that engine and there is no such information or caution anywhere. (and it doesn't make sense anyway for something this large as Joe has indicated). The temperature limit on the regulators is 80*C and rotax insists that it be installed in the engine compartment. While there is an optional additional heat sink available for regulator B it's still an order of magnitude too small to handle that kind of heat. Ken On 12/02/2021 11:43 AM, user9253 wrote: > > Here is a quote from Van's Aircraft FLIGHT TRAINING SUPPLEMENT: > https://www.vansaircraft.com/wp-content/uploads/2020/10/RV-12iS-FTS-4.pdf page 6-6 > >> The Rotax 912 iS is equipped with two voltage regulators, one for each generator on the engine. These regulators reject any unused electrical power as heat. Allowing the power usage to fall below 7 amps for extended periods of time may damage the regulators, especially on hot days. > That can not be true can it? Suppose that 21 amps are available but not > used by the aircraft electrical system. 21 amps x 14 volts = 300 watts > of heat that must be dissipated by the voltage regulators. > Don't modern permanent magnet voltage regulators work by shutting off the > output during part of the AC cycle using SCRs that are in series with the output? > > -------- > Joe Gores > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=500656#500656 > > ________________________________ Message 4 _____________________________________ Time: 10:44:59 AM PST US Subject: AeroElectric-List: Re: Kitfox vertical fin antenna opportunities From: "Eric Page" user9253 wrote: > It took me awhile to realize that the vertical black object going through the > middle of the ribs is actually the com antenna and not structural steel. Is that > a black plastic box at the bottom? What is inside of it? And what is the > purpose of the triangular part that you are holding? Thanks > Theoretically the steel tubes will block radio waves fore and aft. But one can > not argue with the success of others. The installation looks good and I think > that you will be happy with the antenna. Yes, the antenna is sort of a fabric tape with, I presume, copper foil elements bonded to it, then encased with a layer of fiberglass and resin. It's about 1" wide and perhaps 0.05" thick. The "box" and triangular object are the same item: a small block of wood (painted black). It's half of the clamp for the bottom end of the antenna. The antenna's feed point is a ~1" cube in the center of the tape, located just behind the diagonal steel tube. The BNC is just visible in the "Finished Installation" photo. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=500658#500658 ________________________________ Message 5 _____________________________________ Time: 10:57:22 AM PST US Subject: Re: AeroElectric-List: Van's Aircraft Statement From: Charlie England On 2/12/2021 10:43 AM, user9253 wrote: > > Here is a quote from Van's Aircraft FLIGHT TRAINING SUPPLEMENT: > https://www.vansaircraft.com/wp-content/uploads/2020/10/RV-12iS-FTS-4.pdf page 6-6 > >> The Rotax 912 iS is equipped with two voltage regulators, one for each generator on the engine. These regulators reject any unused electrical power as heat. Allowing the power usage to fall below 7 amps for extended periods of time may damage the regulators, especially on hot days. > That can not be true can it? Suppose that 21 amps are available but not > used by the aircraft electrical system. 21 amps x 14 volts = 300 watts > of heat that must be dissipated by the voltage regulators. > Don't modern permanent magnet voltage regulators work by shutting off the > output during part of the AC cycle using SCRs that are in series with the output? > > -------- > Joe Gores Easy enough to test empirically, if you have the system. IIRC, early rectifier-regulators really were 'shunt' style regulators, that would align with the warning from Van's. Newer regulator designs do seem to use 'switcher' style voltage control, which should function like typical semiconductors and get hotter as more current flows to the load. No idea what's used in the iS, but you'd hope it would be the more modern type. Charlie -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ________________________________ Message 6 _____________________________________ Time: 01:03:47 PM PST US From: Janet Amtmann Subject: AeroElectric-List: Repair of Apollo GX65 Does anyone know of someone that can repair an old Apollo GX 65 GPS/COM radio? I bought it new many years ago and installed it in my RV6. On power-up it did not work. No xmit or receive. The GPS window lights up and cycles thru the initial tests, so the radio is getting power properly. I get no satisfaction from Garmin who bought the line and then deleted it from stock. I did a bench test and it is not transmitting or receiving. The trays will not accommodate a different radio, I would have to rebuild the whole instrument panel, but I'm leery of purchasing a used one (they are available) and might get one with the same or other problem. At the moment we are flying with a handheld, but that's a PITA. Any information would be welcome. Jurgen Amtmann ------------------------------------------------------------------------------------- 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.