---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Mon 07/24/06: 18 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 06:00 AM - Re: Magneto P leads (FLYaDIVE@aol.com) 2. 06:53 AM - Re: Illuminated DPST Toggle Switches for Audio sources (FLYaDIVE@aol.com) 3. 08:15 AM - Re: Illuminated DPST Toggle Switches for Audio (Sam Marlow) 4. 08:28 AM - Re: Illuminated DPST Toggle Switches for Audio () 5. 09:01 AM - Re: Illuminated DPST Toggle Switch- Whoops (FLYaDIVE@aol.com) 6. 09:54 AM - Re: Magneto P leads (Robert L. Nuckolls, III) 7. 02:52 PM - Heated pitot tube connections (William Crook) 8. 03:31 PM - Re: Heated pitot tube connections (FLYaDIVE@aol.com) 9. 06:04 PM - Magneto P leads () 10. 06:04 PM - Re: Heated pitot tube connections (Bob McCallum) 11. 07:20 PM - Re: Heated pitot tube connections (Robert L. Nuckolls, III) 12. 07:20 PM - VHF antenna mounting (William Gill) 13. 07:30 PM - Re: Heated pitot tube connections (Robert L. Nuckolls, III) 14. 07:53 PM - Re: Heated pitot tube connections (B Tomm) 15. 07:58 PM - Re: VHF antenna mounting (Jeff Moreau) 16. 08:14 PM - Re: VHF antenna mounting (William Gill) 17. 08:57 PM - Re: Heated pitot tube connections (DonVS) 18. 09:29 PM - Re: Heated pitot tube connections (Robert L. Nuckolls, III) ________________________________ Message 1 _____________________________________ Time: 06:00:38 AM PST US From: FLYaDIVE@aol.com Subject: Re: AeroElectric-List: Magneto P leads --> AeroElectric-List message posted by: FLYaDIVE@aol.com In a message dated 7/24/06 1:55:30 AM Eastern Daylight Time, dean.psiropoulos@verizon.net writes: [sniped] > My question has to > do with grounding the P lead out on magneto which is what lectric Bob > recommends for lowest system noise. I assume that the fiber washer is there > to keep the P lead terminal from grounding the threaded stud to the "shiny > metal nut" that surrounds the plastic that the stud projects out of. If so, > can I use two ring terminals on the coax, one with a much larger ring placed > under the fiber washer which will serve as the return grounding path and > then place a smaller ring terminal (connected to the other wire in the > coax)on top of the fiber washer (which is on top of the larger ring terminal > contacting the shiny metal nut) under the nut that goes on the stud and not > have to worry about magneto grounding somewhere else on the engine? I'm > just trying to not have to strip a whole bunch of shield off the P lead for > grounding at a separate location and this looks like it should work but I > know nothing about magnetos so I'm not sure if my hypothesis is correct. I > hope you can decipher what I trying to say. Thanks. > > Dean Psiropoulos > RV-6A N197DM > Stringing wire (still) =========================================== Dean: Simple answer is NO! DO NOT TOUCH THE FIBER WASHER OF THE MAG. You will be sorry ... Very sorry. There is a Ground screw not very far from the Fiber washer - Use that. That ground screw is for the Shield. I don't know how you can ground the 'P' Lead anywhere else than at the Mag Switch. Sure you could install a relay or solid-state device under the cowl right next to the Mag to keep your leads short but the simple and what I feel is the proper solution is just to use basic mil-spec shielded wire ... Connect the center lead to the center screw of the Mag and the shielded lead to the case ground. YES, you are correct, keep the exposed/stripped wires as short as possible. BUT! Don't stress the wires. The other end of the shielded wire is connected to the Mag Switch(s). The Switch(s) in the RUN position OPENS the Ground between the center lead and the Ground side of the Mag Switch(s). The shielded wire is there for noise suppression. It is grounded at BOTH ends, Mag and Switch(s). Maybe I'm getting word picky but you do not STRIP the shielding from the wire. You separate the shield and center conductor. And there is a trick in doing that so that 'not a single shield wire strand becomes broken'. Trick - It is called the BEAST trick. 1 - Determine how much conductor and shield you will need so there is NO strain. Of course short wires are better, but not so short that you have a broken wire and a Hot Mag. 2 - This is the hard part. Remove the jacket from the wire - This is done by bending the wire back 90 to 180 Deg and NICKING the wire using a razor. You do NOT need to cut down to the shield. Nick the wire, bend it and the wire will do the rest of the job. Now remove the jacket. 3 - Get a sharp thin ~1/8" Dia. scribe - At the base of the exposed shield use the scribe to separate the shielding exposing the center conductor. Work the shield back and away to so you can see 4x (times) the diameter of the center conductor. 4 - Bend the wire at the exposed area 180 Deg. 5 - Use the scribe to hook under the center conductor and pull the free end UP and OUT of the shield. 6 - You are done ... No Nick, No stray strands - No errors. Finish the ends which ever way you wish. Crimp on lugs are usually my choice. Barry "Chop'd Liver" "Show them the first time, correct them the second time, kick them the third time." Yamashiada ________________________________ Message 2 _____________________________________ Time: 06:53:36 AM PST US From: FLYaDIVE@aol.com Subject: Re: AeroElectric-List: Illuminated DPST Toggle Switches for Audio sources --> AeroElectric-List message posted by: FLYaDIVE@aol.com In a message dated 7/22/06 9:01:25 PM Eastern Daylight Time, scc_ron@yahoo.com writes: > Anybody know where I can find ON/NONE/OFF switches with independent lighting? > I bought several from B and C (and they were special order) that don't > seperate the 12 volt light on the toggle from the on/off circuits I wish to > activate. If I were to put a hot wire to the radio equipment, it would fry > the unit I wish to activate. All I want to do is get a lighted toggle that > tells me the other circuit in the switch is closed (ON) without also giving > that circuit any charge. Thanks in advance. > Ron > N8ZD - flying in two weeks! ========================= Ron: An ON/NONE/OFF is the same thing as an ON/OFF (SPST). As for the Lighted part ... That is simple ... That is part of the switch, just a separate lug where you split the power IN to the Light and the control IN of the switch. They do it that way so IF you wanted the light to come ON ... ONLY when the switch is on you simply put the jumper to the output side of the switch. Want the light ON all the time then the jumper goes to the input side of the switch. For me, it is more important to be able to find the switch at night than to know if it is on or off. Switch position which I can feel tells me if it is ON or Off. BASIC RULE: Down or Out is OFF. If the switch is Down or pulled Out it is Off. Not always true but most of the time. There are some switches that change in color from ON to Off, if you want a light indicator. Barry "Chop'd Liver" "Show them the first time, correct them the second time, kick them the third time." Yamashiada ________________________________ Message 3 _____________________________________ Time: 08:15:24 AM PST US From: Sam Marlow Subject: Re: AeroElectric-List: Illuminated DPST Toggle Switches for Audio http://www.aerocraftparts.com/Categories.aspx?Category=38940ec0-b260-4e9f-a23c-b80ff8e89c67 Good luck, Sam Marlow FLYaDIVE@aol.com wrote: >--> AeroElectric-List message posted by: FLYaDIVE@aol.com > >In a message dated 7/22/06 9:01:25 PM Eastern Daylight Time, >scc_ron@yahoo.com writes: > > > >>Anybody know where I can find ON/NONE/OFF switches with independent >> >> >lighting? > > >> I bought several from B and C (and they were special order) that don't >>seperate the 12 volt light on the toggle from the on/off circuits I wish to >>activate. If I were to put a hot wire to the radio equipment, it would fry >>the unit I wish to activate. All I want to do is get a lighted toggle that >>tells me the other circuit in the switch is closed (ON) without also giving >>that circuit any charge. Thanks in advance. >> Ron >> N8ZD - flying in two weeks! >> >> >========================= >Ron: > >An ON/NONE/OFF is the same thing as an ON/OFF (SPST). >As for the Lighted part ... That is simple ... That is part of the switch, >just a separate lug where you split the power IN to the Light and the control IN >of the switch. > >They do it that way so IF you wanted the light to come ON ... ONLY when the >switch is on you simply put the jumper to the output side of the switch. Want >the light ON all the time then the jumper goes to the input side of the switch. > >For me, it is more important to be able to find the switch at night than to >know if it is on or off. Switch position which I can feel tells me if it is ON >or Off. > >BASIC RULE: Down or Out is OFF. If the switch is Down or pulled Out it is >Off. Not always true but most of the time. > >There are some switches that change in color from ON to Off, if you want a >light indicator. > >Barry >"Chop'd Liver" > >"Show them the first time, correct them the second time, kick them the third >time." >Yamashiada > > > > > > > > > ________________________________ Message 4 _____________________________________ Time: 08:28:25 AM PST US From: Subject: Re: AeroElectric-List: Illuminated DPST Toggle Switches for Audio --> AeroElectric-List message posted by: > >>Anybody know where I can find ON/NONE/OFF switches with independent > >> > >> > >lighting? Ron, Check with your local Carling Technologies distributer. Carling makes the LT series of toggle switches. You can get them with a single color or two different colors to decern between ON and OFF. See http://toggle-switches.carlingtech.com/illuminated-toggle-switch__48.asp http://www.carlingtech.com/pdf/CarlingSW_LT.pdf They also make several series of lighted rocker switches. See http://rocker-switches.carlingtech.com/index.asp Charlie Kuss ________________________________ Message 5 _____________________________________ Time: 09:01:31 AM PST US From: FLYaDIVE@aol.com Subject: Re: AeroElectric-List: Illuminated DPST Toggle Switch- Whoops --> AeroElectric-List message posted by: FLYaDIVE@aol.com -> AeroElectric-List message posted by: FLYaDIVE@aol.com In a message dated 7/22/06 9:01:25 PM Eastern Daylight Time, scc_ron@yahoo.com writes: > Anybody know where I can find ON/NONE/OFF switches with independent lighting? > I bought several from B and C (and they were special order) that don't > seperate the 12 volt light on the toggle from the on/off circuits I wish to > activate. If I were to put a hot wire to the radio equipment, it would fry > the unit I wish to activate. All I want to do is get a lighted toggle that > tells me the other circuit in the switch is closed (ON) without also giving > that circuit any charge. Thanks in advance. > Ron > N8ZD - flying in two weeks! ========================= Ron: An ON/NONE/OFF is the same thing as an ON/OFF (SPST). Ron: I used the term SPST ... It should have been DPST. The procedure and everything else is still the same. Why do you need a DPST? I am guessing ... Current handling capabilities? If not, then you can tie two or more devices to the same switch (SPST). Barry "Chop'd Liver" "Show them the first time, correct them the second time, kick them the third time." Yamashiada ________________________________ Message 6 _____________________________________ Time: 09:54:03 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Magneto P leads --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 01:39 AM 7/24/2006 -0400, you wrote: >--> AeroElectric-List message posted by: "DEAN PSIROPOULOS" > > >I'm wondering about connecting the P leads at the magneto. Looking at the >top of the (Slick) magneto I removed the nut and star washer and found an >insulating fiber washer. Looking under the washer, there is the threaded >stud which projects from a piece of white plastic that is in turn surrounded >by a shiny piece of metal that looks like a large nut. My question has to >do with grounding the P lead out on magneto which is what lectric Bob >recommends for lowest system noise. I assume that the fiber washer is there >to keep the P lead terminal from grounding the threaded stud to the "shiny >metal nut" that surrounds the plastic that the stud projects out of. If so, >can I use two ring terminals on the coax, one with a much larger ring placed >under the fiber washer which will serve as the return grounding path and >then place a smaller ring terminal (connected to the other wire in the >coax)on top of the fiber washer (which is on top of the larger ring terminal >contacting the shiny metal nut) under the nut that goes on the stud and not >have to worry about magneto grounding somewhere else on the engine? I'm >just trying to not have to strip a whole bunch of shield off the P lead for >grounding at a separate location and this looks like it should work but I >know nothing about magnetos so I'm not sure if my hypothesis is correct. I >hope you can decipher what I trying to say. Thanks. I'm not familiar with all the variations on the magneto connection schemes . . . the safe thing to recommend is that you not disassemble the terminal assembly beyond the removal of a nut or screw intended to accept the p-lead connection. Most of my readers have reported reasonably handy screws either on the mag house (or they've gone all the way down to the magneto mounting studs) to find a handy ground for the p-lead shields. Getting long leads out from under a shield is pretty easy. See: http://aeroelectric.com/articles/shldwire/shldwire.html Bob . . . --------------------------------------------------------- < What is so wonderful about scientific truth...is that > < the authority which determines whether there can be > < debate or not does not reside in some fraternity of > < scientists; nor is it divine. The authority rests > < with experiment. > < --Lawrence M. Krauss > --------------------------------------------------------- ________________________________ Message 7 _____________________________________ Time: 02:52:58 PM PST US From: William Crook Subject: AeroElectric-List: Heated pitot tube connections I have a standard heated pitot tube. The instructions call for an AN-3115 connector to terminate the power and ground leads. Alas (I love using that word...), I don't have this little gem. Looking on the B&C site, I don't see anything resembling what I need. AS&S has the phenolic connector, but it is really pricey at $88.50. The terminals are sinply two straight rods extending from the pitot tube chassis, and I think I could craft some female spade fittings to slip on, and securing it with some RTV. Obviously, it would be a sad day if these two leads were to short, but all of these $88.50's keep adding up. Sometimes, when the widget looks very straightfoward, I tend to try and get cheap ;-) Thoughts? ________________________________ Message 8 _____________________________________ Time: 03:31:36 PM PST US From: FLYaDIVE@aol.com Subject: Re: AeroElectric-List: Heated pitot tube connections --> AeroElectric-List message posted by: FLYaDIVE@aol.com In a message dated 7/24/06 5:55:36 PM Eastern Daylight Time, will@willcrook.com writes: > The terminals are sinply two straight rods extending from the pitot tube > chassis, and I think I could craft some female spade fittings to slip on, and > securing it with some RTV. Obviously, it would be a sad day if these two > leads were to short, but all of these $88.50's keep adding up. Sometimes, > when the widget looks very straightfoward, I tend to try and get cheap ;-) > > Thoughts? ================================== Will: I like the way you think. You will have to do a little hunting but there are round slip on connectors just like the spade design but only one half and larger in size to handle the current. The ceramic type is exactly that but with a ceramic case. As for them shorting or causing a problem ... Distance is always a great insulator and you could also make one from a small piece of Teflon ... If you go this way you will need something that can handle the heat. Will, you said something that caught my eye ... Ground leads ... Do not use the planes ground as your return line. Run a separate wire so that you have B+ and Neg wires going out there. THEN if you wish ground the Negative out at the wing tip. This will greatly help with other wiring such as your Strobe and Nav Lights. Most problems over time are related to a poor ground. Barry "Chop'd Liver" "Show them the first time, correct them the second time, kick them the third time." Yamashiada ________________________________ Message 9 _____________________________________ Time: 06:04:50 PM PST US From: Subject: AeroElectric-List: Magneto P leads --> AeroElectric-List message posted by: 7/24/2006 Responding to an AeroElectric-List message previously posted by: "DEAN PSIROPOULOS" Hello Dean, I was pleased to see your question on the list. It shows that you have an inquisitive mind and are thinking, and it shows that you are willing to seek out additional information. Your question creates an opportunity for a bit of information to be exchanged that may benefit others as well. On the case of your Slick magneto very near the P (primary coil) lead stud is a threaded hole. Beside this threaded hole are the raised letters GND. This is an abbreviation for the word GROUND. When the magneto comes new from Slick there is a Phillips head machine screw threaded into this hole. The purpose of this screw is to provide for a grounding contact to the magneto case. Accepted procedure is to comb out a length of shielding from the magneto end of the shielded P lead, twist the shield wires together, and crimp a ring terminal of the appropriate size on the end of the combed out and twisted together shield wires. The shield ring terminal is then fastened to the magneto case by the aforementioned GND screw. The center lead of the P lead wire also gets a ring terminal crimped on to it and this ring terminal is fastened to the P lead stud such that it does not contact the magneto case in any way. On the cockpit end of the P lead the shield and the center wire are connected to the terminals of a switch such that when the switch is in the OFF position the shield and the center wire are connected together. This grounds out the magneto back to its case and prevents it from sparking the spark plugs. When the ignition switch is in the ON position the shield wire and the center wire of the P lead are separated from each other and the magneto can spark the plugs when properly rotated. The term P lead is a bit of a misnomer because the lead does not connect directly to the primary coil of the magneto. Instead the P lead connects to a stud coming out of a capacitor (sometimes called a condenser in the older manuals) in the primary coil circuitry. Also in the primary coil circuitry are the magneto points. The capacitor in this circuit serves to suppress arcing between the points when they are being opened. The stud on the end of the capacitor also serves as a convenient point to ground out the primary coil output via the P lead connection back to a switch as described above when one does not want the magneto to be firing the spark plugs. Looking forward to your next question. OC <> ________________________________ Message 10 ____________________________________ Time: 06:04:50 PM PST US From: "Bob McCallum" Subject: Re: AeroElectric-List: Heated pitot tube connections Barry; I may be mistaken, but I believe this advice on grounding is totally contrary to what has been taught on this list for the past several years. My understanding of Lectric Bob's advice and lessons on grounding, are, that local grounds are OK for such things as pitot heat, position lights etc. but that running a ground wire to a wingtip for an accessory, as you suggest, and then grounding it there as well is a no-no as this is likely to create a ground loop. Grounds should be local OR run to the "forest of tabs" ground point on the firewall. They should not be both for any single item. (and local grounds are only used for certain specific items as described in "The Connection".) Bob McC ----- Original Message ----- Sent: Monday, July 24, 2006 6:27 PM > --> AeroElectric-List message posted by: FLYaDIVE@aol.com > > In a message dated 7/24/06 5:55:36 PM Eastern Daylight Time, > will@willcrook.com writes: > > > The terminals are sinply two straight rods extending from the pitot tube > > chassis, and I think I could craft some female spade fittings to slip on, > and > > securing it with some RTV. Obviously, it would be a sad day if these two > > leads were to short, but all of these $88.50's keep adding up. Sometimes, > > when the widget looks very straightfoward, I tend to try and get cheap ;-) > > > > Thoughts? > ========================= ========= > Will: > > I like the way you think. You will have to do a little hunting but there are > round slip on connectors just like the spade design but only one half and > larger in size to handle the current. The ceramic type is exactly that but with > a ceramic case. > As for them shorting or causing a problem ... Distance is always a great > insulator and you could also make one from a small piece of Teflon ... If you go > this way you will need something that can handle the heat. > > Will, you said something that caught my eye ... Ground leads ... Do not use > the planes ground as your return line. Run a separate wire so that you have B+ > and Neg wires going out there. THEN if you wish ground the Negative out at > the wing tip. This will greatly help with other wiring such as your Strobe and > Nav Lights. Most problems over time are related to a poor ground. > > Barry > "Chop'd Liver" > > "Show them the first time, correct them the second time, kick them the third > time." > Yamashiada ________________________________ Message 11 ____________________________________ Time: 07:20:49 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Heated pitot tube connections --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 08:57 PM 7/24/2006 -0400, you wrote: >Barry; > >I may be mistaken, but I believe this advice on grounding is totally >contrary to what has been taught on this list for the past several >years. My understanding of Lectric Bob's advice and lessons on grounding, >are, that local grounds are OK for such things as pitot heat, position >lights etc. but that running a ground wire to a wingtip for an accessory, >as you suggest, and then grounding it there as well is a no-no as this is >likely to create a ground loop. Grounds should be local OR run to the >"forest of tabs" ground point on the firewall. They should not be both for >any single item. (and local grounds are only used for certain specific >items as described in "The Connection".) > >Bob McC This needs some clarification. "Ground Loops" ALWAYS exist when multiple accessories ground to DIFFERENT parts of the airplane. Ground loops are not always evil. The problems arise when potential victims (radios, audio systems, instrumentation, etc) SHARE the airframe (or distributed ground system in a composite) with potential antagonists like alternators. Alternators do not become antagonists until they're asked to supply substantial currents for the purpose of running high power accessories like landing lights and pitot heaters. Discharged batteries are also "high power" loads while being replenished. I had a builder complain about alternator noise in a system that went away after a few minutes of flight . . . his battery was the major antagonistic contributor to ground loop noise that went away when the battery assumed recharge. Now, one may ground all the antagonists you wish to the airframe or distributed ground 'cause all they can do is yell at each other and as long as they a deaf . . . ist macht nicht. The things that are vulnerable are immune from any yelling going on elsewhere as long as their respective and collective grounds DO NOT participate in the noisy ground loop. Best yet, if all potential victims share a single point (or slightly distributed single point as shown in the audio systems chapter) then there will be order in the world. Hence the suggestion about local grounds. Notice that all the devices called out are not potential victims and they participate only in the generation of noise because they're high power loads for the noisiest device in the airplane, the alternator. So you may ground them at any convenient location for good bonding without regard to potential noise issues. Bob . . . ________________________________ Message 12 ____________________________________ Time: 07:20:49 PM PST US From: "William Gill" Subject: AeroElectric-List: VHF antenna mounting Hello All, I'm mounting two VHF bent whip antennas on the belly of an RV-7. Where can I find information pertaining to doubler requirement? Also, a cork gasket/seal is installed between the Comant antenna base and the fuselage skin - is the antenna base grounded to the fuselage via the mounting screws since the cork seal insulates the antenna base? Thanks. Bill Gill RV-7 wiring Lee's Summit, MO ________________________________ Message 13 ____________________________________ Time: 07:30:45 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Heated pitot tube connections --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 02:44 PM 7/24/2006 -0700, you wrote: >I have a standard heated pitot tube. The instructions call for an AN-3115 >connector to terminate the power and ground leads. Alas (I love using >that word...), I don't have this little gem. Looking on the B&C site, I >don't see anything resembling what I need. AS&S has the phenolic >connector, but it is really pricey at $88.50. The terminals are sinply >two straight rods extending from the pitot tube chassis, and I think I >could craft some female spade fittings to slip on, and securing it with >some RTV. Obviously, it would be a sad day if these two leads were to >short, but all of these $88.50's keep adding up. Sometimes, when the >widget looks very straightfoward, I tend to try and get cheap ;-) > >Thoughts? I have a client who asked me to look into alternative sources for the AN3115 connector. I've studied some of the connection science issues and looked at the processes available. Problem is that the connection at the pitot tube is subject to elevated operating temperatures + extended 3x inrush currents. Building a really GOOD AN3115 is not a trivial task. Problem is that this is such a low volume part that by the time we tool up to build a decent part, the non-recurring costs are breathtaking. If it were my airplane (and if I were supplying pitot tubes) I would silver solder 12", 14AWG Teflon pigtails onto the pitot tube pins. Cover the joint in Teflon heat shrink and then make connections to the airplane at the ends of the pigtails with some attractive, robust splice. PIDG knife splices covered with heat shrink tickle my fancy. Very straightforward, very cheap. Bob . . . --------------------------------------------------------- < What is so wonderful about scientific truth...is that > < the authority which determines whether there can be > < debate or not does not reside in some fraternity of > < scientists; nor is it divine. The authority rests > < with experiment. > < --Lawrence M. Krauss > --------------------------------------------------------- ________________________________ Message 14 ____________________________________ Time: 07:53:11 PM PST US From: "B Tomm" Subject: RE: AeroElectric-List: Heated pitot tube connections What about soldering wire female leads to the terminals. Bevan RV7A finish kit _____ [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of William Crook Sent: Monday, July 24, 2006 2:44 PM I have a standard heated pitot tube. The instructions call for an AN-3115 connector to terminate the power and ground leads. Alas (I love using that word...), I don't have this little gem. Looking on the B&C site, I don't see anything resembling what I need. AS&S has the phenolic connector, but it is really pricey at $88.50. The terminals are sinply two straight rods extending from the pitot tube chassis, and I think I could craft some female spade fittings to slip on, and securing it with some RTV. Obviously, it would be a sad day if these two leads were to short, but all of these $88.50's keep adding up. Sometimes, when the widget looks very straightfoward, I tend to try and get cheap ;-) Thoughts? ________________________________ Message 15 ____________________________________ Time: 07:58:40 PM PST US From: Jeff Moreau Subject: Re: AeroElectric-List: VHF antenna mounting What position are you mounting them in. I am getting ready for bent whips on the belly of my RV8A. I was wondering how close together you are mounting them. Are they side=by side, or in line with the centerline of the fuselage. Any info would be appreciated. Jeff Moreau Virginia Beach, VA On Jul 24, 2006, at 10:15 PM, William Gill wrote: > Hello All, > > > I=92m mounting two VHF bent whip antennas on the belly of an RV-7. > Where can I find information pertaining to doubler requirement? > Also, a cork gasket/seal is installed between the Comant antenna > base and the fuselage skin ' is the antenna base grounded to the > fuselage via the mounting screws since the cork seal insulates the > antenna base? Thanks. > > > Bill Gill > > RV-7 wiring > > Lee=92s Summit, MO > > ________________________________ Message 16 ____________________________________ Time: 08:14:18 PM PST US From: "William Gill" Subject: RE: AeroElectric-List: VHF antenna mounting Hello Jeff, I'm mounting them side by side.they are about 32" apart. Bill -----Original Message----- [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Jeff Moreau Sent: Monday, July 24, 2006 9:56 PM What position are you mounting them in. I am getting ready for bent whips on the belly of my RV8A. I was wondering how close together you are mounting them. Are they side=by side, or in line with the centerline of the fuselage. Any info would be appreciated. Jeff Moreau Virginia Beach, VA On Jul 24, 2006, at 10:15 PM, William Gill wrote: Hello All, I'm mounting two VHF bent whip antennas on the belly of an RV-7. Where can I find information pertaining to doubler requirement? Also, a cork gasket/seal is installed between the Comant antenna base and the fuselage skin - is the antenna base grounded to the fuselage via the mounting screws since the cork seal insulates the antenna base? Thanks. Bill Gill RV-7 wiring Lee's Summit, MO ________________________________ Message 17 ____________________________________ Time: 08:57:09 PM PST US From: "DonVS" Subject: RE: AeroElectric-List: Heated pitot tube connections --> AeroElectric-List message posted by: "DonVS" -----Original Message----- [mailto:owner-aeroelectric-list-server@matronics.com]On Behalf Of Robert L. Nuckolls, III Sent: Monday, July 24, 2006 7:28 PM snip would silver solder 12", 14AWG Teflon pigtails onto the pitot tube pins. Cover the joint in Teflon heat shrink and then make connections to the airplane at the ends of the pigtails with some attractive, robust splice. PIDG knife splices covered with heat shrink tickle my fancy. Very straightforward, very cheap. Bob . . . Bob, Is the silver solder just for heat resistance? If I am not mistaken silver solder is not as good a conductor as tin/lead, or is that an old wives tale? Don --------------------------------------------------------- < What is so wonderful about scientific truth...is that > < the authority which determines whether there can be > < debate or not does not reside in some fraternity of > < scientists; nor is it divine. The authority rests > < with experiment. > < --Lawrence M. Krauss > --------------------------------------------------------- ________________________________ Message 18 ____________________________________ Time: 09:29:48 PM PST US From: "Robert L. Nuckolls, III" Subject: RE: AeroElectric-List: Heated pitot tube connections --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 08:53 PM 7/24/2006 -0700, you wrote: >--> AeroElectric-List message posted by: "DonVS" > > >-----Original Message----- >[mailto:owner-aeroelectric-list-server@matronics.com]On Behalf Of Robert >L. Nuckolls, III >Sent: Monday, July 24, 2006 7:28 PM > > >snip > would silver solder 12", 14AWG Teflon pigtails onto the pitot > tube pins. Cover the joint in Teflon heat shrink and then make > connections to the airplane at the ends of the pigtails with > some attractive, robust splice. PIDG knife splices covered with > heat shrink tickle my fancy. > > Very straightforward, very cheap. > > Bob . . . > >Bob, >Is the silver solder just for heat resistance? If I am not mistaken silver >solder is not as good a conductor as tin/lead, or is that an old wives tale? >Don Dunno . . . but solder as an electrical conductor is seldom a performance issue irrespective of how much resistance it may have . . . there's so little solder in the electrical path that wide variability of conductance in various solders is insignificant. 63/37 tin/lead melts at sufficiently low temperature to be at risk of coming loose on SOME pitot tube installations. The tube manufacturers often recommend that pins supplied with the AN3115 connector be connected to wires with "high temperature solder". Silver solder is certainly not at-risk for softening and it alloys better with the corrosion resistant pins on the pitot tube. Bob . . .