---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Thu 12/17/09: 19 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 05:50 AM - Re: Kind of off topic. Speed sensor needed. (Sam Hoskins) 2. 05:50 AM - Re: Stec 30 Autopilot & GPSS conversion (Greenbacks, UnLtd.) 3. 05:50 AM - Re: Stec 30 Autopilot & GPSS conversion (Greenbacks, UnLtd.) 4. 06:37 AM - I need a larger photo, please (DeWitt Whittington) 5. 07:09 AM - Re: Kind of off topic. Speed sensor needed. (Robert L. Nuckolls, III) 6. 07:20 AM - Re: RV-8 - Instrument Panel Power Coat & Silkscreen... () 7. 07:56 AM - Re: Warm-up Problem (Deene Ogden) 8. 08:14 AM - Re: Feedback while transmitting (Michael Hilderbrand) 9. 08:44 AM - Re: Kind of off topic. Speed sensor needed. (Robert L. Nuckolls, III) 10. 09:33 AM - Re: I need a larger photo, please (Matt Dralle) 11. 09:33 AM - Re: Kind of off topic. Speed sensor needed. (Sam Hoskins) 12. 09:54 AM - Re: Warm-up Problem (David & Elaine Lamphere) 13. 10:42 AM - Re: Feedback while transmitting (Robert L. Nuckolls, III) 14. 11:44 AM - Re: Feedback while transmitting (ROGER & JEAN CURTIS) 15. 02:28 PM - Re: I need a larger photo, please (Stein Bruch) 16. 02:57 PM - HID bulb types () 17. 04:25 PM - Re: HID bulb types (XeVision) 18. 06:01 PM - Follow Up to Power Opti-Miser (Dennis Johnson) 19. 07:42 PM - Re: Follow Up to Power Opti-Miser (Robert L. Nuckolls, III) ________________________________ Message 1 _____________________________________ Time: 05:50:30 AM PST US Subject: Re: AeroElectric-List: Kind of off topic. Speed sensor needed. From: Sam Hoskins Bob, I think that 1 millisecond accuracy would be fine. I think, just my opinion, if we could determine speed to one digit, it would be fine, eg. 234.6 mph. Of course, two digits would be better. Thanks to all who contributed suggestions. I have complied and posted all of them to the SARL racers group. For anyone who may be interested and wish to join, the e-mail list is at: http://groups.yahoo.com/group/SARL-Racers/ Sam On Tue, Dec 15, 2009 at 9:54 AM, Robert L. Nuckolls, III < nuckolls.bob@aeroelectric.com> wrote: > nuckolls.bob@aeroelectric.com> > > > On 15 Dec 2009, at 4:46 AM, Robert L. Nuckolls, III wrote: > > Yes, photo cells looking straight up though a tube of 2 - 4" > and length adjusted so that subtended angle of view is sufficiently > small that the "shadow" of any part of the aircraft blocks the > skylight. There are some self-calibrating level sensor circuits > that will adjust for slow variability in sky light levels. > > E: This would work well - even if the light sensor wasn't in a tube, > calibrated correctly, the change from direct sunlight to shadow should be > enough to trigger a timing device of some description. > > You need to constrain the view angle . . .preferably > without the use of optics. Long tubes seem the simplest > approach. > > E: I would suggest two or three sensors in a line across the runway. Then > use the second or third sensor that is triggered so that you know it's the > wing that's causing the shadow both times, and not the wing on the first > end, and the spinner on the second (which would skew results). > > That would be useful . . . depending on how "loose" > the rules are for alignment with the runway ceneterline, > an array of senors of any number could be used. > > E: Even a very simple microprocessor would be able to do the timing > accurately enough, and could display the result on an LCD screen without too > much effort. > > Sure, the jellybean PIC products offer one set of > solutions. > > E: There is one downside to this, if you're keen on using either end of a > runway, I guess you're looking for about 1km between sensors. That's a lot > of wire to wind up at the end of each competition! There may be some simple > radio interfaces that could be substituted...? > > Ten years ago, I helped some RC racers craft a timing system > that required communication over a many acres of event > venue. Off the shelf, 433 MHz transmiter and receiver > modules provided links. Controlling atency and jitter in > detecting event-edges would be a critical design goal. > > Assuming 300 mph (440 f/s) over 5000 feet of runway > (11.3 seconds) a .1% accuracy in timing would call for > control of variability to less than 10 milliseconds. > If shorter runs are anticipated, the number gets tighter. > +/-1 millisecond would probably be a practical design goal. > > Sam. Define "accurate". What are the design goals for > the reduction of uncertainty? > > Bob . . . > > ________________________________ Message 2 _____________________________________ Time: 05:50:51 AM PST US From: "Greenbacks, UnLtd." Subject: AeroElectric-List: Re: Stec 30 Autopilot & GPSS conversion I'd like to make contact with anyone in this group who has recent experience or knowledge with regard to wiring this autopilot. I have a couple of questions/issues which may ultimately be of interest here but please contact me directly for now. Thanks, Angier Ames Lancair 360 N4ZQ ________________________________ Message 3 _____________________________________ Time: 05:50:52 AM PST US From: "Greenbacks, UnLtd." Subject: AeroElectric-List: Re: Stec 30 Autopilot & GPSS conversion I'd like to make contact with anyone in this group who has recent experience or knowledge with regard to wiring this autopilot. I have a couple of questions/issues which may ultimately be of interest here but please contact me directly for now. Thanks, Angier Ames Lancair 360 N4ZQ ________________________________ Message 4 _____________________________________ Time: 06:37:29 AM PST US From: DeWitt Whittington Subject: AeroElectric-List: I need a larger photo, please Matt, Your panel looks super. However, I can only read, maybe, the N number. Is there a way for you to post a larger photo of your panel so I can see more in detail how your powder coated panel labels read and look. And exactly how were the labels done? We are just about to have our panel powder coated and labeled. Boy, is it difficult to figure out the wording for each switch, etc. Dee DeWitt (Dee) Whittington 406 N Mulberry St Richmond, VA 23220-3320 (804) 358-4333 phone and fax SKYPE: hilltopkid dee.whittington@gmail.com ________________________________ Message 5 _____________________________________ Time: 07:09:42 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Kind of off topic. Speed sensor needed. At 07:28 AM 12/17/2009, you wrote: >Bob, I think that 1 millisecond accuracy would be fine. I think, >just my opinion, if we could determine speed to one digit, it would >be fine, eg. 234.6 mph. Of course, two digits would be better. It's technically feasible to get about any resolution you want but the costs of producing a user-friendly system can go up really fast as you add those decimal points! I did a drag track clocking system design many many moons ago wherein we used telescopes looking across the track at a strong light source. Magnification was so high that the entire illumination disk (6" roundel) filled the field of view in the telescope eyepiece. This system was vacuum tube sensor systems driving an HP counter/timer that was also vacuum tube and used columns of neon bulbs to display measured result. In this instance, ambient light had no measurable effect on triggering accuracy. It worked equally well at night or bright sunlight. Further, uncertainty of trigger timing was limited to the time it took for the vehicle to cross the 6" field of view. So back in 1974 or thereabouts, we had 0.1 mS resolution and 1 mS accuracy of timing over the distance between sensors. I think they installed them 10' apart at the end of the track. At 150 f/s, the interval of interest was about 66 milliseconds so we could calculate speed with an accuracy of about 1.5% Folks were impressed by that kind of capability back then. Photo-detectors looking at sky-light through tubes (or even cheap telescopes) offers a means by which uncertainty in trigger timing (dd/dt) can be very small. But as others pointed out, very small apertures, require resolution of the differences between a prop spinner and leading edge of wing. So an array of sensors driving a discriminator calling for two or more sensors to be triggered before the hack is marked seems to offer a solution. The use of radio to tie the ends of the system together is quite practical. There are inexpensive, off the shelf timers available with micro-second resolution/accuracy. The proof of the pudding is in the sensor array. Bob . . . --------------------------------------- ( . . . a long habit of not thinking ) ( a thing wrong, gives it a superficial ) ( appearance of being right . . . ) ( ) ( -Thomas Paine 1776- ) --------------------------------------- ________________________________ Message 6 _____________________________________ Time: 07:20:54 AM PST US Subject: RE: AeroElectric-List: RV-8 - Instrument Panel Power Coat & Silkscreen... From: Great job Matt - Don't forget to look out the window while watching those DVD's :) I'm going to ditch my aluminum stuff and cut mine out of Carbon Fiber. That stuff is so strong and easy to work with, I see not use in paying the painter. Enjoy. Glenn E. Long -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Matt Dralle Sent: Wednesday, December 16, 2009 10:30 PM Subject: AeroElectric-List: RV-8 - Instrument Panel Power Coat & Silkscreen... Listers, I got the instrument panel back from power coat and silkscreen today and I just couldn't wait to stick the instruments in to see what it looks like! Sweet!! I can hardly wait to get it mounted and powered back up! Matt Dralle RV-8 #82880 N998RV http://www.mattsrv8.com - Matt's RV-8 Construction Blog Final Assembly ________________________________ Message 7 _____________________________________ Time: 07:56:58 AM PST US From: "Deene Ogden " Subject: Re: AeroElectric-List: Warm-up Problem You should check your alternator to see if the diode bridge is OK. If a diode fails, then the output from the alt will be very noisy and especially at higher output levels. Deene Ogden RV8 CFII, MEI, CFIG ________________________________ Message 8 _____________________________________ Time: 08:14:57 AM PST US From: Michael Hilderbrand Subject: Re: AeroElectric-List: Feedback while transmitting Thanks Gus, =0A=0AMy headphone jacks (and headsets) are in close proximity of the antenna.--The jacks are located on the first former behind the s eat and the antenna is just above all that on-top of the turtle deck. =0A =0AI will move things around and see what happens.--=0A-Michael Hilde rbrand=0ADerby, Kansas=0AHttp://www.kansasflying.com =0A=0A=0A=0A=0A_______ _________________________=0AFrom: Gus Schlegel =0ATo: aer oelectric-list@matronics.com=0ASent: Wed, December 16, 2009 8:07:39 PM=0ASu bject: Re: AeroElectric-List: Feedback while transmitting=0A=0A--> AeroElec tric-List message posted by: Gus Schlegel =0A=0AMichael H ilderbrand wrote:=0A> I am getting a loud feedback noise in my headset when I press the PTT.- It only seems to happen 70% of the time - having the e ngine running, or not, is of no difference.- Today in the hangar I presse d the PTT and could hear the feedback coming out of the speakers of my jam- box radio several feet away! The radio on the jam-box was on but the volume turned all the way down. When I unplugged it I could no longer hear the no ise in the jam-box, but it was VERY present in my headphones. Of course, th is in a new installation in my airplane - flown the plane 2 times now.- N ot being able to her yourself talk is frustrating! Oh.. yeah, the receiving end ALWAYS hears me "loud & clear."- Anyone have a good FIRST place to s tart looking to fix this problem. It seems- like it might be a simple fix .... a ground maybe? Inadequate antenna?- Thanks!=0A>- Michael Hilderbr and=0A> Derby, Kansas=0A> Http://www.kansasflying.com=0A> *=0A> *=0AI had t he same problem, intermittent feedback - until I started moving my headset cables around and voila! At a certain position in relation to the antenna c able it started squealing. I rerouted my antenna cable and the problem went -=- - - - - - - - - - - - - - - -Matt Drall = ________________________________ Message 9 _____________________________________ Time: 08:44:27 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Kind of off topic. Speed sensor needed. > The use of radio to tie the ends of the system together > is quite practical. There are inexpensive, off the shelf > timers available with micro-second resolution/accuracy. > The proof of the pudding is in the sensor array. What is the size of the "box" that the aircraft must stay inside and what height above the ground is the lower edge of that box? I occurs to me that if you have a 100' wide by 100' high box with lower edge at 100' agl, the number of sensors required to cover that up-look area with any resolution could be pretty big. Fortunately, they're cheap and easy to build. So is the electronics for resolving the presence of an airplane "shadow" Bob . . . //// (o o) ===========o00o=(_)=o00o======== < Go ahead, make my day . . . > < show me where I'm wrong. > ================================ ________________________________ Message 10 ____________________________________ Time: 09:33:37 AM PST US From: Matt Dralle Subject: Re: AeroElectric-List: I need a larger photo, please At 06:34 AM 12/17/2009 Thursday, you wrote: > >Matt, > >Your panel looks super. However, I can only read, maybe, the N number. Is there a way for you to post a larger photo of your panel so I can see more in detail how your powder coated panel labels read and look. > >And exactly how were the labels done? We are just about to have our panel powder coated and labeled. Boy, is it difficult to figure out the wording for each switch, etc. > >Dee > >DeWitt (Dee) Whittington >406 N Mulberry St >Richmond, VA 23220-3320 >(804) 358-4333 phone and fax >SKYPE: hilltopkid >dee.whittington@gmail.com Here is the full-resolution shot of the panel. I used a textured power coat that looks really nice. Same as I used on the engine baffles. The silk screen looks okay. In retrospect, I think that I would have power coated the panel gloss black, did the silk screen, then had them put a clear texture power coat over the top. For the right side control panel, I'm having them use a "label" the full size of the panel. The stuff looks just like the power coated panel in both texture and color. The lettering, however is super crisp. I'll post some pictures when I get it back. I also had them make up some similar labels for the various remote controls like the Alternate Air and Cabin Heat. Matt Dralle RV-8 #82880 N998RV http://www.mattsrv8.com Final Assembly ________________________________ Message 11 ____________________________________ Time: 09:33:39 AM PST US Subject: Re: AeroElectric-List: Kind of off topic. Speed sensor needed. From: Sam Hoskins The box would be the width of the runway, with the pilot striving to stay pretty much on the center line. Probably as low as 20 feet and as high as 100 feet - maybe 75. On Thu, Dec 17, 2009 at 10:41 AM, Robert L. Nuckolls, III < nuckolls.bob@aeroelectric.com> wrote: > nuckolls.bob@aeroelectric.com> > > > The use of radio to tie the ends of the system together >> is quite practical. There are inexpensive, off the shelf >> timers available with micro-second resolution/accuracy. >> The proof of the pudding is in the sensor array. >> > > What is the size of the "box" that the aircraft must stay inside > and what height above the ground is the lower edge of that box? > > I occurs to me that if you have a 100' wide by 100' high > box with lower edge at 100' agl, the number of sensors > required to cover that up-look area with any resolution > could be pretty big. Fortunately, they're cheap and easy > to build. So is the electronics for resolving the presence > of an airplane "shadow" > > > Bob . . . > //// > (o o) > ===========o00o=(_)=o00o======== > < Go ahead, make my day . . . > > < show me where I'm wrong. > > ================================ > > ________________________________ Message 12 ____________________________________ Time: 09:54:55 AM PST US From: "David & Elaine Lamphere" Subject: Re: AeroElectric-List: Warm-up Problem If that was the case, wouldn't the frequency of the shriek be lower?? - and continue to be noisy all the time? It ouzzles me that on stops where I re-fuel and startup again - there's no noise right after startup... Thanks for your input - I thought I'd get a lot more suggestions from the group. Everyone must be shopping :-) Dave (N365DL) PS. 40.5 hrs today! Phase 1 complete!!! ----- Original Message ----- From: Deene Ogden To: aeroelectric-list@matronics.com Sent: Thursday, December 17, 2009 10:54 AM Subject: Re: AeroElectric-List: Warm-up Problem You should check your alternator to see if the diode bridge is OK. If a diode fails, then the output from the alt will be very noisy and especially at higher output levels. Deene Ogden RV8 CFII, MEI, CFIG ________________________________ Message 13 ____________________________________ Time: 10:42:09 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Feedback while transmitting At 10:09 AM 12/17/2009, you wrote: >Thanks Gus, > >My headphone jacks (and headsets) are in close proximity of the >antenna. The jacks are located on the first former behind the seat >and the antenna is just above all that on top of the turtle deck. > >I will move things around and see what happens. Just a reminder to the List about risks for the proximity of certain things . . . The Comm transmit antenna is the STRONGEST potential antagonist for deleterious effects of EMC in the airplane. Microphone wiring (indeed all audio wiring) is a close second place to thermocouple wiring for most likely victims to RF interference. The mic and thermocouple wires are generally limited as to routing and connections. The antenna is by far the easiest thing to get as far as practical from the firewall and cockpit. Bob . . . //// (o o) ===========o00o=(_)=o00o======== < Go ahead, make my day . . . > < show me where I'm wrong. > ================================ ________________________________ Message 14 ____________________________________ Time: 11:44:46 AM PST US From: "ROGER & JEAN CURTIS" Subject: RE: AeroElectric-List: Feedback while transmitting Just a reminder to the List about risks for the proximity of certain things . . . The Comm transmit antenna is the STRONGEST potential antagonist for deleterious effects of EMC in the airplane. Microphone wiring (indeed all audio wiring) is a close second place to thermocouple wiring for most likely victims to RF interference. The mic and thermocouple wires are generally limited as to routing and connections. The antenna is by far the easiest thing to get as far as practical from the firewall and cockpit. Bob Would I be correct in assuming that there should be very little interference picked up in the mic and thermocouple wires if they are run next to the com coax, as long as they are not near the antenna, i.e. bundled together behind the instrument panel? Roger ________________________________ Message 15 ____________________________________ Time: 02:28:27 PM PST US From: "Stein Bruch" Subject: RE: AeroElectric-List: I need a larger photo, please Quick question Matt....did you have that thing powder coated in a flat/matte finish? Cheers, Stein do not archive ________________________________ Message 16 ____________________________________ Time: 02:57:44 PM PST US From: Subject: AeroElectric-List: HID bulb types I'm piecing together an HID landing light system and need to decide between D1S and D2S bulbs. D1S has the igniter in the bulb, and D2S has it in the ballast. Is there any advantage in eliminating the relatively short high-voltage run between the ballast and bulb by using the D1S type? The bulb and ballast will be in the wingtip along with a VOR antenna. Will the bulb type make a difference if I decide to install a wig-wag flasher? David Barrett RV-7 Wings ________________________________ Message 17 ____________________________________ Time: 04:25:02 PM PST US Subject: AeroElectric-List: Re: HID bulb types From: "XeVision" flylists(at)dbarrett.net wrote: > I'm piecing together an HID landing light system and need to decide between > D1S and D2S bulbs. D1S has the igniter in the bulb, and D2S has it in the > ballast. Is there any advantage in eliminating the relatively short > high-voltage run between the ballast and bulb by using the D1S type? The > bulb and ballast will be in the wingtip along with a VOR antenna. Will the > bulb type make a difference if I decide to install a wig-wag flasher? > > David Barrett > RV-7 Wings The noise difference between D1S and D2S is significant, especially if pulsing because of the noisy on pulses. D1S is what you definitely want with the high voltage igniter at the bulb, not in the ballast. If you use D2S anyway, at least make sure the HV cable to the bulb and the socket are shielded. The bulb types will not matter for wig-wag. D2S or D1S are both ok for that as long as you warm the bulbs up (steady on) for 20 seconds minimum and 30 seconds is even better, before you start wigwag. Make sure you are pulsing at about 1Hz (no more than 1/2 second off on each channel and at least 1/2 second on for each pulse). This is for good bulb life. Many HID ballasts will have a short life if you wig-wag. Most of them (automotive) were not designed for this punishment. The SAE design specs for Automotive ballasts are only ~20,000 starts. That is one of many reasons why XeVision designs and makes our own ballasts. Designed from the start (ground up) for Wig-wag capability. Also, on our newest ballast systems, it is not required to interrupt main power to the ballast for the wig-wag function. Our new XePulse II provides a very small trigger signal to the ballast for on/off wig-wag function. This extra 3rd wire only needs to be 20 or 22 awg for mechanical strength. Our newer ballasts use a 3 wire input connector, 2 wires for + and - and the 3rd for the on/off wig-wag trigger. This is a much better way to control wig-wag in HID systems. The XePulse II only weighs about an ounce and can trigger about 250 ballasts per channel (obviously way overkill). It is only about 1.5 X 1.5 X .75 inches and uses a 9 pin d-sub connection. All of this new proprietary ballast and HID wig-wag technology makes for a very quiet (EMI / RFI) system. This wig-wag system IS patented as of Nov 10, 2009 -------- LED still has a long way to go to compete with HID as a landing light. This is true in terms of total lumens and reach (distance). Read this topic online here: http://forums.matronics.com/viewtopic.php?p=278002#278002 ________________________________ Message 18 ____________________________________ Time: 06:01:07 PM PST US From: "Dennis Johnson" Subject: AeroElectric-List: Follow Up to Power Opti-Miser Bob, thanks so much for replying to my post about my experience with low power factor appliances. I see that I need to study some more so I can understand this better. I've stubbed my toe on power factor questions before, so I'm not surprised. You've asked good questions that I'll address after I study up! Thanks, Dennis Time: 06:10:15 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Re: Power Opti-Miser At 11:30 AM 12/14/2009, you wrote: >My house is not connected to the power grid, which makes me both a >power generator and a power consumer. If we look at this issue from >that perspective, things change. >My conclusion is that both sides of this camp might be at least >partially correct. Since residential power meters measure real >watts, the residential consumer isn't penalized for the extra power >the utility has to generate to run bad power factor appliances. >However, the utility has to generate the extra electricity, even >though they aren't getting paid for it (which is already built into >the rate structure). The utility doesn't have to generate any extra watts. It only has to choose wire sizes that carry an artificially high current that doesn't participate in the running of devices with poor p.f. > But if consumers could do something to improve the power factor > of their appliances, it would reduce the amount of electricity > produced, reducing the unfavorable environmental consequences of > making electricity. That would be good for everyone (assuming the > environmental effects of making the correction devices resulted in > a net gain, of course). The "goodness" comes only from the fact that the same work can be done over smaller wires with less heating of the wires. A significant savings when your transmission lines are measured in miles instead of feet and transformers are in 100's of KVAR instead of 2 KVAR. > >I have no opinion as to whether the devices under discussion >actually reduce apparent watts. It may well be that the most recent >appliances include better internal power factor correction. I know >that the last batch of compact fluorescent bulbs I bought seem to >have very good power factor. Yes. And the folks who do switchmode power supplies for computers and other electronics have been prodded by dozens of articles for how p.f. can be improved for over 20 years. See chapter 11 in Volume 2 of the basic electronics document below . . . http://www.allaboutcircuits.com/vol_2/index.html If your AC power generation devices are pseudo sine wave (finely stepped square wave) then the output power has more harmonic content than the stuff coming out of the wall. This puts a whole new twist on the problem of optimizing power factor. Have you measured the aggregate power factor for household loads on your system? It may well be that the losses are so small that doing anything about them is economically impractical. When talking about small losses, keep in mind that your house wiring is not zero ohms material. Depending on how long the runs are, you may find that copper losses are already significant and only slightly aggravated by the effects of p.f. Lord Kelvin reminded us often that without access to the real numbers, our knowledge is of a meager kind. Your situation cries out for a long term study of aggregate quality for your total household load. A true RMS voltmeter, ammeter and power-factor meter recording to a hard drive over a long period of time would give you a basis for doing more detailed studies followed up by useful changes to your hardware. ________________________________ Message 19 ____________________________________ Time: 07:42:02 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Follow Up to Power Opti-Miser At 07:56 PM 12/17/2009, you wrote: >Bob, thanks so much for replying to my post about my experience with >low power factor appliances. I see that I need to study some more >so I can understand this better. I've stubbed my toe on power >factor questions before, so I'm not surprised. You've asked good >questions that I'll address after I study up! My pleasure sir. I'd like to know more about your homepower experiences. At the least, an off-list conversation would be welcome . . . but I'm pretty certain that out of 1800 subscribers, there's a significant interest in the practice and technology. Shucks, some of the folks might have remote hangars they'd like to "power up". What ever you're comfortable with is fine with me. 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