---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Wed 09/23/09: 12 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 01:53 AM - 5V from aircraft power - best practice? (Peter Mather) 2. 02:13 AM - Re: 5V from aircraft power - best practice? (pmather) 3. 03:29 AM - Re: Aerobatics and Instrument Damage (tomcostanza) 4. 04:00 AM - Re: Re: Aerobatics and Instrument Damage (Werner Schneider) 5. 05:43 AM - Re: Re: Aerobatics and Instrument Damage (BobsV35B@aol.com) 6. 06:54 AM - Re: Re: 5V from aircraft power - best practice? (David E. Nelson) 7. 06:54 AM - Re: Re: 5V from aircraft power - best practice? (Steve Thomas) 8. 07:39 AM - Re: 5V from aircraft power - best practice? (pmather) 9. 12:42 PM - Re: Re: 5V from aircraft power - best practice? (Robert L. Nuckolls, III) 10. 12:45 PM - iPOD and Squeal (John Markey) 11. 12:48 PM - Re: What size wire? (Robert L. Nuckolls, III) 12. 06:16 PM - Re: strobe lights (Robert L. Nuckolls, III) ________________________________ Message 1 _____________________________________ Time: 01:53:56 AM PST US From: "Peter Mather" Subject: AeroElectric-List: 5V from aircraft power - best practice? ________________________________ Message 2 _____________________________________ Time: 02:13:45 AM PST US Subject: AeroElectric-List: Re: 5V from aircraft power - best practice? From: "pmather" Can anyone tell me why my message sent from outlook are coming through blank? This one sent viam the web forum. Any message was: Hi all I'm building some PIC based circuits to provide some monitoring on my aircraft including interfacing a HMC6343 compass module (very expensive!) and wanted views on the best practice way to derive a clean 5V and 3.3V supply from the aircraft power. My current approach is as follows: 1 amp fuse - reverse polarity protection diodes - transorb and 4700uF capacitor across power/GND inside the diodes. Isolating DC-DC convertor (e.g TRACO TEL 3-2011) which gives 5V out from 10-30V in - MCP1700 low dropout linear regulator to get 3.3V from the 5V rail (very low power required at 3.3V). This is very much a one off so I'm not too worried about cost (especially compared to the compass module) but want something simple, secure, and reliable. Thanks Peter Read this topic online here: http://forums.matronics.com/viewtopic.php?p=264465#264465 ________________________________ Message 3 _____________________________________ Time: 03:29:39 AM PST US Subject: AeroElectric-List: Re: Aerobatics and Instrument Damage From: "tomcostanza" I'm building an all electric RV and am also concerned about the gyros. Could the solution be as simple as installing a switch (or 2 switches ;-) )to power down the gyros when doing aerobatics? I agree it's better to take them out of the airplane, but that's not an option for me. Clear skies, -Tom -------- Clear Skies, Tom Costanza Read this topic online here: http://forums.matronics.com/viewtopic.php?p=264470#264470 ________________________________ Message 4 _____________________________________ Time: 04:00:02 AM PST US From: Werner Schneider Subject: Re: AeroElectric-List: Re: Aerobatics and Instrument Damage Not a good idea for mechanical gyros, they might be damaged more if they do not spin then the other way round. Werner (all electric including instruments) tomcostanza wrote: > > I'm building an all electric RV and am also concerned about the gyros. Could the solution be as simple as installing a switch (or 2 switches ;-) )to power down the gyros when doing aerobatics? I agree it's better to take them out of the airplane, but that's not an option for me. > > Clear skies, > -Tom > > -------- > Clear Skies, > Tom Costanza > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=264470#264470 > > > ________________________________ Message 5 _____________________________________ Time: 05:43:16 AM PST US From: BobsV35B@aol.com Subject: Re: AeroElectric-List: Re: Aerobatics and Instrument Damage Good Morning Tom, Great Question! Wish I knew the answer. Once again, I think I would check with the manufacturer. However, as a point of reference, our answer fifty years ago when most gyros had a caging capability was to turn off the air before the flight and cage the gyros. That seemed to be a good solution at the time. The caging lifted the gyros off the stops, held them securely, and prevented banging of the gimbals. By shutting off the air, the gyroscopic forces were eliminated. Some of the instrument gurus of the day told us that the bearings and axles were still subjected to loads for which they were not designed. The good thing about those days was that we could buy high quality WWII surplus AN flight instruments at a fraction of their cost of manufacture. As I said earlier, the TC and T&B (S-Tec autopilots use a TC as a sensor.} can handle any and all aerobatics comfortably No problem there at all. They are not harmed by aerobatics, but Attitude and Directional Gyros can be. If you use a Bendix/King KG 102A compass system, aerobatics will damage it rapidly. My WAG for the electric Attitude and Directional Gyros is that if you turn them off before the flight so that the gyros are not spinning and restrain yourself to a maximum of two or three G smooth aerobatics (No snap maneuvers), the instruments will not be harmed. As Always, It All depends! Happy Skies, Old Bob AKA Bob Siegfried Downers Grove, IL LL22 Stearman N3977A In a message dated 9/23/2009 5:30:55 A.M. Central Daylight Time, Tom@CostanzaAndAssociates.com writes: --> AeroElectric-List message posted by: "tomcostanza" I'm building an all electric RV and am also concerned about the gyros. Could the solution be as simple as installing a switch (or 2 switches ;-) )to power down the gyros when doing aerobatics? I agree it's better to take them out of the airplane, but that's not an option for me. Clear skies, -Tom -------- Clear Skies, Tom Costanza Read this topic online here: http://forums.matronics.com/viewtopic.php?p=264470#264470 ________________________________ Message 6 _____________________________________ Time: 06:54:25 AM PST US From: "David E. Nelson" Subject: Re: AeroElectric-List: Re: 5V from aircraft power - best practice? Hi Peter, There was some recent discussion on this list regarding the 'blank emails' topic. I think the common problem was that AVG anti-virus was used. If you google for 'AVG anti-virus blank emails' you'll find various threads. Here are a couple of threads that may help you: http://www.zimbra.com/forums/zimbra-connector-outlook/7386-blank-email-body-anti-virus.html http://techrepublic.com.com/5208-23-0.html?forumID=101&threadID=272602&messageID=2581442 Regards, /\/elson On Wed, 23 Sep 2009, pmather wrote: > > Can anyone tell me why my message sent from outlook are coming through blank? This one sent viam the web forum. > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=264465#264465 > ________________________________ Message 7 _____________________________________ Time: 06:54:37 AM PST US Subject: Re: AeroElectric-List: Re: 5V from aircraft power - best practice? From: Steve Thomas You need to select "Plain Text" as your default for sending messages. The mail you sent has some bad HTML code and it shows up as blank unless you select "Raw Source" (if your email program allows that.) Steve Thomas ________________________________________________________________________ On Sep 23, 2009, at 2:12 AM, pmather wrote: > > Can anyone tell me why my message sent from outlook are coming > through blank? This one sent viam the web forum. > > Any message was: > > Hi all > > I'm building some PIC based circuits to provide some monitoring on my > aircraft including interfacing a HMC6343 compass module (very > expensive!) > and wanted views on the best practice way to derive a clean 5V and > 3.3V > supply from the aircraft power. > > My current approach is as follows: > > 1 amp fuse - reverse polarity protection diodes - transorb and 4700uF > capacitor across power/GND inside the diodes. Isolating DC-DC > convertor (e.g > TRACO TEL 3-2011) which gives 5V out from 10-30V in - MCP1700 low > dropout > linear regulator to get 3.3V from the 5V rail (very low power > required at > 3.3V). > > This is very much a one off so I'm not too worried about cost > (especially > compared to the compass module) but want something simple, secure, and > reliable. > > Thanks > > Peter > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=264465#264465 > > ________________________________ Message 8 _____________________________________ Time: 07:39:12 AM PST US Subject: AeroElectric-List: Re: 5V from aircraft power - best practice? From: "pmather" Steve, David Thanks for the info on the emails. I was already using plain text so it is clearly AVG that causes the problems. However, back to the real subject of the email? Best regards Peter Read this topic online here: http://forums.matronics.com/viewtopic.php?p=264526#264526 ________________________________ Message 9 _____________________________________ Time: 12:42:23 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Re: 5V from aircraft power - best practice? > >My current approach is as follows: > >1 amp fuse - reverse polarity protection diodes - transorb and 4700uF >capacitor across power/GND inside the diodes. Isolating DC-DC convertor (e.g >TRACO TEL 3-2011) which gives 5V out from 10-30V in - MCP1700 low dropout >linear regulator to get 3.3V from the 5V rail (very low power required at >3.3V). What you've proposed will be fine. Bob . . . --------------------------------------- ( . . . a long habit of not thinking ) ( a thing wrong, gives it a superficial ) ( appearance of being right . . . ) ( ) ( -Thomas Paine 1776- ) --------------------------------------- ________________________________ Message 10 ____________________________________ Time: 12:45:58 PM PST US From: John Markey Subject: AeroElectric-List: iPOD and Squeal Bob wrote: Okay, 'high pitched' is not alternator noise. It MIGHT be an artifact of the dc/dc converter in your ipod power adapter. I have an identical issue with my SANSA mp3 player. When the screen backlight times out [user setting to 20 sec] the squeal stops. Apparently, the backlighting frequency is horrible for our ears. I pick this up over the plane audio, my car and stand alone ear buds. After 20 seconds, no squeal. Some units are set to remain lit if on external power, so the squeal never stops. Can the screen setting be changed on his iPOD to a shorter time? John in a Glasiar II FT ________________________________ Message 11 ____________________________________ Time: 12:48:06 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: What size wire? At 09:41 PM 9/22/2009, you wrote: > >Bare with me I am learning! My system will follow Z12, but it does >not list a AWG for the connection form the battery relay to the main >buss and from the main bus to the E-buss. Some of the drawings show >a 6 AWG from the battery relay to the main bus, but the wire diagram >from Van's calls out a 8 AWG. So this got me to thinking how do I >determine the size wire that will go here. I understand wires >sizing to individual components but how does one figure a wire feeding a bus? As a general rule, fat wires that do not carry starter currents are picked to carry alternator currents. Many builders using 4AWG fat wires for battery installations near the engine simply use 4AWG for the altenrator b-lead and main bus too. But if your alternator is 60A or smaller, 6AWG is fine for these two slots. Size the main-bus/e-bus jumper according to e-bus loads. Same philosophy for the e-bus alternate feed path from the battery bus. >Lastly due to panel space my main buss is going to be in two rows, >how do I make the interconnection between the two, bolt a strip of >buss bar material between the buss that holds the CBs. should I >connect the two rows of breakers at both ends giving a redundant >path to the second row. To be clear my main buss is 2 rows of >breakers and the E-buss is one row, for 3 rows total. Thanks for the help. Here's how Beech does it . . . http://aeroelectric.com/Pictures/Breakers/Breaker_Panel_Busing_2.jpg http://aeroelectric.com/Pictures/Breakers/Breaker_Panel_Busing_1.jpg http://aeroelectric.com/Pictures/Breakers/Breaker_Panel_Busing_0.jpg Bob . . . --------------------------------------- ( . . . a long habit of not thinking ) ( a thing wrong, gives it a superficial ) ( appearance of being right . . . ) ( ) ( -Thomas Paine 1776- ) --------------------------------------- ________________________________ Message 12 ____________________________________ Time: 06:16:02 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: strobe lights At 12:48 PM 9/19/2009, you wrote: >For anyone interested in this sort of thing, here is some >information on test standards. >http://physics.nist.gov/Divisions/Div844/facilities/photo/Flash/flash.html thank you sir. I've downloaded to my reference library Bob . . . --------------------------------------- ( . . . a long habit of not thinking ) ( a thing wrong, gives it a superficial ) ( appearance of being right . . . ) ( ) ( -Thomas Paine 1776- ) --------------------------------------- ------------------------------------------------------------------------------------- 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.