---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Thu 03/22/12: 14 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 06:20 AM - Stobes (Eric M. Jones) 2. 09:42 AM - Re: Annunciator lights (Robert L. Nuckolls, III) 3. 11:11 AM - Re: ELT Antenna (Noel Loveys) 4. 11:53 AM - Re: Re: wingtip vor antenna - SWR Meter (Noel Loveys) 5. 12:05 PM - Re: Stobes (Robert L. Nuckolls, III) 6. 12:14 PM - Re: Annunciator lights (Noel Loveys) 7. 02:44 PM - Re: Annunciator lights (Robert L. Nuckolls, III) 8. 02:48 PM - Re: Re: wingtip vor antenna - SWR Meter (Robert L. Nuckolls, III) 9. 04:39 PM - Re: ELT Antenna (Kelly McMullen) 10. 06:30 PM - Re: ELT Antenna (Tim Andres) 11. 06:36 PM - Re: ELT Antenna (Noel Loveys) 12. 08:05 PM - Fw: Portable Transponder () 13. 08:35 PM - Re: ELT Antenna (BobsV35B@aol.com) 14. 09:47 PM - Re: ELT Antenna (The Kuffels) ________________________________ Message 1 _____________________________________ Time: 06:20:56 AM PST US Subject: AeroElectric-List: Stobes From: "Eric M. Jones" Here's more work for Bob to do in his "free" time. I have seen many questions on how to quiet strobes and would like to make the following observation: Having a central strobe power pack and running long wires to the wingtips (or to the rim of your flying saucer) is a recipe for RFI/EMI. A much more sensible design is to have the capacitors and trigger coil, located at the strobe tube. Strobe synchronization is simple to achieve. Noise would be gone. Whelen actually makes remote power packs, but at a price that is affordable only to Wall Street hedge fund managers. So a DIY version of a lighter weight "distributed" replacement for the standard Whelen strobe power pack would be a good solution to noise. Estimated weight savings 2 pounds. Not trivial. I have designed LED strobes in this fashion. Only position-light power wiring to the wingtip is required. This design merely pulses the synchronization to fire the strobes. -------- Eric M. Jones www.PerihelionDesign.com 113 Brentwood Drive Southbridge, MA 01550 (508) 764-2072 emjones(at)charter.net Read this topic online here: http://forums.matronics.com/viewtopic.php?p=369131#369131 ________________________________ Message 2 _____________________________________ Time: 09:42:51 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Annunciator lights >Thanks Bob! I'll have to check if its the resistors that failed next >time I get to the hangar but I noticed some of the on-line >LED/resistor calculators call for a 1/2 w resistor and the ones >installed in the fixtures look like 1/8w. I'll report back but have >already bought new LEDs to fix them with and in fact found some >blinking ones to boot that I'll use on my OP light. One caveat on blinking LEDs . . . they're not very bright. When you're designing annunciators for airplanes, your dynamic range for ambient lighting is huge . . . especially for a bubble canopy airplane. I've used blinking LEDs in SERIES with high intensity devices with some success. But the most elegant approach for attention getting is to have a dedicated hardware flasher for the LED. It can be pretty simple: Emacs! This little flasher board made with surface mount components can be as small as .4" on a side, maybe even smaller. If you find that you need to over-drive an LED to meet your illumination design goals (e.g. say 50mA from a 14v source) the series resistor would be something on the order of 10/.05 or 200 ohms. 10 Volts dropped at 50 mA is 500 milliwatts . . . so using a 1W resistor would not be a bad idea for keeping surface temperatures down. If you've had failures of the COTS components then it doesn't much matter whether it was due to resistor or lamp failure . . . the events demand evaluation and modification of the design to achieve a useful level of confidence. Bob . . . ________________________________ Message 3 _____________________________________ Time: 11:11:14 AM PST US From: "Noel Loveys" Subject: RE: AeroElectric-List: ELT Antenna In that case if even on an OBAM aircraft the ELT and transponder must be installed or signed off by a certified AME (Canada) or A&P (U.S.) Noel From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Kelly McMullen Sent: March 21, 2012 8:26 PM Subject: RE: AeroElectric-List: ELT Antenna The minimum for use of ELTs is to demonstrate that the complete system meets the TSO. Good luck with doing that with a roll your own antenna of unknown impedance and SWR. ELTs and transponders are two items on OBAM aircraft that must comply with the TSO. Noel wrote: It sure would be... but for amateur aircraft you might be able to use your own antenna. Noel From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Ed Holyoke Sent: March 20, 2012 10:18 PM Subject: Re: AeroElectric-List: ELT Antenna Have to look at your ELT installation instructions. The ELT is TSOed and might require that you use their antenna. ________________________________ Message 4 _____________________________________ Time: 11:53:31 AM PST US From: "Noel Loveys" Subject: RE: AeroElectric-List: Re: wingtip vor antenna - SWR Meter Reading the page on this meter I assume it is not a good meter for use on RF below 100mHz. Noel From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Robert L. Nuckolls, III Sent: March 21, 2012 9:38 PM Subject: RE: AeroElectric-List: Re: wingtip vor antenna - SWR Meter At 05:42 PM 3/21/2012, you wrote: Yes, it is a problem the diodes in this meter are not nearly fast enough to break the RF (Radio Frequency) of VHF into digital segments needed to measure SWR. This unit is usable for frequencies 30 mHz and below. You may find a serviceable meter on eBay. If you buy a Bird Wattmeter make sure the element for 100-250 mHz comes with it. The Bird products are the gold standard for RF wattmeters. A few months ago we had some discussion on the List about the HF SWR meters common to CB radio frequencies and below. These are not suited to VHF as their sampled transmission line is too long with respect to a wavelength at the frequencies of interest for VHF. They tend to give 'good' readings to poor antennas. We also had some discussions about this device: Emacs! Which you can get off eBay for about $60 postage paid. http://tinyurl.com/7cl4bba I purchased one of these and found it a quite good value. Reasonably accurate for power readings down into the 100 milliwatt range. The one I have here on my bench is spoken for and will be out of here next week . . . but the folks offering it on eBay have plenty more. Be sure to get two N-Male/BNC-Female adapters. Emacs! http://tinyurl.com/6m7ujmw These are about $2.50 each postage paid. Bob . . . ________________________________ Message 5 _____________________________________ Time: 12:05:47 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Stobes At 08:18 AM 3/22/2012, you wrote: > >Here's more work for Bob to do in his "free" time. > >I have seen many questions on how to quiet strobes and would like to >make the following observation: > >Having a central strobe power pack and running long wires to the >wingtips (or to the rim of your flying saucer) is a recipe for >RFI/EMI. A much more sensible design is to have the capacitors and >trigger coil, located at the strobe tube. Strobe synchronization is >simple to achieve. Noise would be gone. As you've noted, there are several designs qualified for TC aircraft where the power conditioning is adjacent to the strobe tube. But I would offer that centralized supplies are also qualified, i.e. have passed DO-160 conducted and radiated emissions. So if installed with attention to good practice for treatment of shields, they should present no greater noise problem in an OBAM aircraft than they do in a TC aircraft. >Whelen actually makes remote power packs, but at a price that is >affordable only to Wall Street hedge fund managers. So a DIY version >of a lighter weight "distributed" replacement for the standard >Whelen strobe power pack would be a good solution to noise. >Estimated weight savings 2 pounds. Not trivial. Those are slick . . . but they're a relatively low volume product in comparison with the central supply configuration and they take up more room in what might be a more crowded space. Hence the higher cost that is not well tolerated in the SE propeller driven market. All the strobes on turbine aircraft have local power supplies but as you've noted, these are breathtakingly expensive. >I have designed LED strobes in this fashion. Only position-light >power wiring to the wingtip is required. This design merely pulses >the synchronization to fire the strobes. What kind of voltages/currents and duty cycles are involved? I've seen some LED anti-collision protects offered to HBC while I was still there but folks who showed them to me were unable or reluctant to discuss design details. What's the architecture for wiring up large arrays of LED's. The tail strobe I saw had about 36 leds in it. The guy thought it was 4 strings of 9 each. At 4 volts per led in an overdriven pulse mode, one comes to believe that a pulsed, 36 volt constant current supply is used. What approach has been most attractive in your experience? EMC issues for these supplies is a bit simpler. There's little probability of 'output noise' due to flashing and the operating frequency of the switchmode power supply is generally much higher . . . hence easier to filter . . . assuming the designer recognizes the need for a filter. We discovered this lower level design goal in the Luxeon power supplies that folks have been using in their wingtips. I've sold perhaps 50 filtered supplies over the past 4-5 years and perhaps half that number of filter boards for folks who already had supply modules. Bob . . . ________________________________ Message 6 _____________________________________ Time: 12:14:20 PM PST US From: "Noel Loveys" Subject: RE: AeroElectric-List: Annunciator lights Bob: The specs say 240Kmcd@300m=8BA . What exactly is a Kmcd? I have some ideas but none seems to fit unless this lamp will blister paint at ten feet.. Noel From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Robert L. Nuckolls, III Sent: March 21, 2012 10:17 PM Subject: Re: AeroElectric-List: Annunciator lights At 03:55 PM 3/21/2012, you wrote: Hey gang! I built an annunciator panel using these LED's: http://tinyurl.com/85r8duf Now that Im flying I find they are failing almost weekly. I need to replace them or fix the problem. They incorporate an integral resistor and are rated at 12V. I'm looking for a more durable replacement, maybe something that could be retrofitted into the existing lens as the led and resistor will slide out the back side. What colors are you needing? Can you send me one of these fixtures . . . or at least take some good pix of the disassembled hardware as supplied. LEDs are not generally very fragile. Are you sure it's the LED that's failing and not the resistor? Some years ago we had some discussion about LED fragility and life vs. intensity here on the List. I took issue with a few readers who cited 'not to exceed' ratings for LEDs lest they depart for the happy glowing ground. I took a 10mm LED rated at 30 mA and wired it to a wall-wart biased up at about 4x that rating. I plugged it into an outlet in my garage and left it. You could see rather well in a darkened garage from the emitted light. Over a year later, I took it off the wall still illuminated. I didn't measure it's light output to see if it degraded but it certainly didn't go into gross failure. For use in annunciators where the lights are OFF most of the time, it might be a good idea to over-drive the LEDs in the interest of sun-light viewable performance. There are some honk'n LEDs available. I bought some 10mm reds and greens from this guy for a courtroom, table-top demonstrator . . . http://tinyurl.com/7jlgymk Very adequate for getting one's attention in a well lit courtroom. This seller http://tinyurl.com/7n75xu2 has some killer whites rated at 1W. These might do what you want depending on the ability of your caps to set the color when illuminated with white led. This much power in an LED probably calls for some heat-sinking . . . but you may find that you can run them a lot cooler and still get the necessary light. Bob . . . ________________________________ Message 7 _____________________________________ Time: 02:44:37 PM PST US From: "Robert L. Nuckolls, III" Subject: RE: AeroElectric-List: Annunciator lights At 02:12 PM 3/22/2012, you wrote: >Bob: > > >The specs say 240Kmcd@300m=8BA .=C2 What exactly >is a Kmcd?=C2 I have some ideas but none seems to >fit unless this lamp will blister paint at ten feet.. > > It's a bit of silliness . . . an mCd is a milli-candella. Or 1/1000th of one candella http://en.wikipedia.org/wiki/Candela 240,000 mCandelas reduces down to 240 Candelas, the "K" and "m" wipe each other out. Bob . . . ________________________________ Message 8 _____________________________________ Time: 02:48:07 PM PST US From: "Robert L. Nuckolls, III" Subject: RE: AeroElectric-List: Re: wingtip vor antenna - SWR Meter At 01:52 PM 3/22/2012, you wrote: >Reading the page on this meter I assume it is not a good meter for >use on RF below 100mHz. It's accuracy will degrade as you depart the manufacturer's specified range of performance. If you buy a 'slug' for a Bird wattmeter Emacs! It is characterized for a power level and a range of frequencies for which it will meet the manufacturer's specs for accuracy. The 'Red Dot' SWR meter is simply a power meter with a 'fixed slug'. Bob . . . ________________________________ Message 9 _____________________________________ Time: 04:39:50 PM PST US From: Kelly McMullen Subject: Re: AeroElectric-List: ELT Antenna Who installs it has nothing to do whether it complies. It simply must be installed in compliance with the manufacturer's instructions, which ensure TSO compliance. In theory the DAR inspecting the aircraft should check that, but are not likely to look too closely. The person doing the condition inspection annually must also ensure compliance with the test requirements in Part 91. On 3/22/2012 11:09 AM, Noel Loveys wrote: > > In that case if even on an OBAM aircraft the ELT and transponder must > be installed or signed off by a certified AME (Canada) or A&P (U.S.) > > Noel > > *From:*owner-aeroelectric-list-server@matronics.com > [mailto:owner-aeroelectric-list-server@matronics.com] *On Behalf Of > *Kelly McMullen > *Sent:* March 21, 2012 8:26 PM > *To:* aeroelectric-list@matronics.com > *Subject:* RE: AeroElectric-List: ELT Antenna > > The minimum for use of ELTs is to demonstrate that the complete system > meets the TSO. Good luck with doing that with a roll your own antenna > of unknown impedance and SWR. ELTs and transponders are two items on > OBAM aircraft that must comply with the TSO. > > Noel wrote: > > It sure would be... but for amateur aircraft you might be able to use > your own antenna. > > Noel > > *From:*owner-aeroelectric-list-server@matronics.com > > [mailto:owner-aeroelectric-list-server@matronics.com > ] *On Behalf Of > *Ed Holyoke > *Sent:* March 20, 2012 10:18 PM > *To:* aeroelectric-list@matronics.com > > *Subject:* Re: AeroElectric-List: ELT Antenna > > Have to look at your ELT installation instructions. The ELT is TSOed > and might require that you use their antenna. > > * * > * * > ** > ** > ** > ** > ** > *http://www.matronics.com/Navigator?AeroElectric-List* > ** > ** > *http://forums.matronics.com* > ** > ** > ** > *http://www.matronics.com/contribution* > ** > * * > * > > > * ________________________________ Message 10 ____________________________________ Time: 06:30:02 PM PST US Subject: Re: AeroElectric-List: ELT Antenna From: Tim Andres I just had mine inspected by the FAA for A/W cert. and the issue never came u p at all and I do have a non TSO 'd antenna on the transponder. FWIW, I thin k that's about the norm . I know of several others with the same experience. Tim Sent from my iPad On Mar 22, 2012, at 11:09 AM, "Noel Loveys" wrote: > In that case if even on an OBAM aircraft the ELT and transponder must be i nstalled or signed off by a certified AME (Canada) or A&P (U.S.) > > Noel > > From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelect ric-list-server@matronics.com] On Behalf Of Kelly McMullen > Sent: March 21, 2012 8:26 PM > To: aeroelectric-list@matronics.com > Subject: RE: AeroElectric-List: ELT Antenna > > The minimum for use of ELTs is to demonstrate that the complete system mee ts the TSO. Good luck with doing that with a roll your own antenna of unknow n impedance and SWR. ELTs and transponders are two items on OBAM aircraft th at must comply with the TSO. > > Noel wrote: > It sure would be... but for amateur aircraft you might be able to use your own antenna. > > Noel > > From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelect ric-list-server@matronics.com] On Behalf Of Ed Holyoke > Sent: March 20, 2012 10:18 PM > To: aeroelectric-list@matronics.com > Subject: Re: AeroElectric-List: ELT Antenna > > Have to look at your ELT installation instructions. The ELT is TSOed and m ight require that you use their antenna. > > > http://www.matronics.com/Navigator?AeroElectric-List > http://forums.matronics.com > http://www.matronics.com/contribution > > > ========================== ========= ========================== ========= ========================== ========= ========================== ========= > ________________________________ Message 11 ____________________________________ Time: 06:36:13 PM PST US From: "Noel Loveys" Subject: RE: AeroElectric-List: ELT Antenna In this country any appliance on a certified aircraft with certain exceptions has to be installed by or checked by a certified AME ( aircraft maintenance engineer ) and the installation has to be documented in the airframe log book and noted if there is a separate log book for the appliance. One of the things I do not like about the new ELT is that aircraft cannot borrow another ELT while one is out having scheduled service done. In the past the AMO I worked for had a "loaner" ELT that we would put in aircraft so they wouldn't have to fly without one... Which is legal for up to 90 days. In fact even a licensed AME is not allowed to change the batteries on an ELT it has to be done by an approved Avionics tech or an approved avionics shop. Amateur built aircraft are another quintal of fish... They don't even have to carry an ELT. Mind I don't know anyone who is stupid enough to fly this land without one. Noel -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Kelly McMullen Sent: March 22, 2012 9:06 PM Subject: Re: AeroElectric-List: ELT Antenna --> Who installs it has nothing to do whether it complies. It simply must be installed in compliance with the manufacturer's instructions, which ensure TSO compliance. In theory the DAR inspecting the aircraft should check that, but are not likely to look too closely. The person doing the condition inspection annually must also ensure compliance with the test requirements in Part 91. On 3/22/2012 11:09 AM, Noel Loveys wrote: > > In that case if even on an OBAM aircraft the ELT and transponder must > be installed or signed off by a certified AME (Canada) or A&P (U.S.) > > Noel > > *From:*owner-aeroelectric-list-server@matronics.com > [mailto:owner-aeroelectric-list-server@matronics.com] *On Behalf Of > *Kelly McMullen > *Sent:* March 21, 2012 8:26 PM > *To:* aeroelectric-list@matronics.com > *Subject:* RE: AeroElectric-List: ELT Antenna > > The minimum for use of ELTs is to demonstrate that the complete system > meets the TSO. Good luck with doing that with a roll your own antenna > of unknown impedance and SWR. ELTs and transponders are two items on > OBAM aircraft that must comply with the TSO. > > Noel wrote: > > It sure would be... but for amateur aircraft you might be able to use > your own antenna. > > Noel > > *From:*owner-aeroelectric-list-server@matronics.com > > [mailto:owner-aeroelectric-list-server@matronics.com > ] *On Behalf Of > *Ed Holyoke > *Sent:* March 20, 2012 10:18 PM > *To:* aeroelectric-list@matronics.com > > *Subject:* Re: AeroElectric-List: ELT Antenna > > Have to look at your ELT installation instructions. The ELT is TSOed > and might require that you use their antenna. > > * * > * * > ** > ** > ** > ** > ** > *http://www.matronics.com/Navigator?AeroElectric-List* > ** > ** > *http://forums.matronics.com* > ** > ** > ** > *http://www.matronics.com/contribution* > ** > * * > * > > > * ________________________________ Message 12 ____________________________________ Time: 08:05:13 PM PST US From: Subject: AeroElectric-List: Fw: Portable Transponder 3/2/2012 Hello John Cammarano, I hope that this helps solve your problem. 'OC' Baker ================================================================= From: "John Delafield" Sent: Thursday, March 22, 2012 4:15 PM Subject: RE: Portable Transponder > Dear Sir, > > We assemble the transponder box using a certified TT 21 or 22 which has > FAA > approval so no worries there. The entire box is not approved by anyone > but > as it is portable I do not think it necessary anyway. > > The altitude encoder is built in to the transponder and it meets the new > 25ft spacing requirement. > > I am pretty sure for your application that you would not need the very > expensive hand made leather case that we normally provide and not having > this would reduce the price to you by about $200. > > Lead time for delivery would be a few weeks. > > I very much hope that we can help you, > > All the best, > > John Delafield > LX avionics Ltd > 07850 950349/01865 374125 > www.lxavionics.co.uk > Company Number 4417407 Registered in England and Wales > VAT GB 793 1777 86 > Registered address (NOT FOR BUSINESS): 30 St Giles, Oxford > ====================================================== From: bakerocb@cox.net [mailto:bakerocb@cox.net] > Sent: 22 March 2012 15:42 > To: johnd@lxavionics.co.uk > Subject: Portable Transponder > > 3/22/2012 > > Hello John, We are seeking a portable airtraffic radar transponder for use > in a small homebuilt (no electrical power) fixed wing airplane in the US. > Your products seen here: > > http://www.lxavionics.co.uk/portables.htm > > appear to offer a solution. > > I have two questions: > > 1) How is the information normally provided to a transponder by an > altitude > encoder for automatic altitude information transmission by the transponder > provided for in your products? > > 2) Are you aware of any regulatory reason (TSO or inspection requirements) > that would make your products not be acceptable for use in the United > States? > > Thanks for your help, > > 'OC' Baker Says: "The best investment we can make is the time and effort > to > gather and understand knowledge." > ________________________________ Message 13 ____________________________________ Time: 08:35:50 PM PST US From: BobsV35B@aol.com Subject: Re: AeroElectric-List: ELT Antenna Good Evening Noel, What country are you discussing? In the USA, every airline pilot regularly flies without an ELT. Personally, I would be happy to do so if it were not an FAA requirement. I do not feel one whit more secure since we were forced to install the ELT. There are a lot of ways to let folks know when and if you need assistance. I think each pilot should be able to make that decision himself or herself. Happy Skies, Old Bob In a message dated 3/22/2012 8:36:50 P.M. Central Daylight Time, noelloveys@yahoo.ca writes: --> AeroElectric-List message posted by: "Noel Loveys" In this country any appliance on a certified aircraft with certain exceptions has to be installed by or checked by a certified AME ( aircraft maintenance engineer ) and the installation has to be documented in the airframe log book and noted if there is a separate log book for the appliance. One of the things I do not like about the new ELT is that aircraft cannot borrow another ELT while one is out having scheduled service done. In the past the AMO I worked for had a "loaner" ELT that we would put in aircraft so they wouldn't have to fly without one... Which is legal for up to 90 days. In fact even a licensed AME is not allowed to change the batteries on an ELT it has to be done by an approved Avionics tech or an approved avionics shop. Amateur built aircraft are another quintal of fish... They don't even have to carry an ELT. Mind I don't know anyone who is stupid enough to fly this land without one. Noel ________________________________ Message 14 ____________________________________ Time: 09:47:46 PM PST US From: "The Kuffels" Subject: Re: AeroElectric-List: ELT Antenna Old Bob says: << Noel, .. What country are you discussing? >> His email address is Canada. His description fits what little I know of Canada's regulatory environment. << I do not feel one whit more secure since we were forced to install the ELT. >> This sentiment conflicts with my direct, personal experience. In Alaska in the 1970s when ELTs were first forced upon us, the false activation rate (especially in very cold weather) and the failure to activate rate (mostly due to poor antenna placement) was depressing. Still ELTs managed to save lives, including mine. The newer GPS augmented 406 MHz system is much more effective, quickly providing a location measured in meters. << There are a lot of ways to let folks know when and if you need assistance. >> Disagree. My Alaska crash occurred about 150 miles from any human habitation. My Idaho mountain crash was over in 15 sec. In the meantime, I was a little busy to let anyone know anything. Although I was flying with two other aircraft, they were unable to get our accurate location to Search & Rescue. Our cell phone got through to 911 long enough to let them know there were survivors but not long enough to provide our accurate location. Our 121.5 MHz ELT gave them a location 5 miles in error. But when they got in the neighborhood the ELT did help a little in narrowing our location. The moral, I want as many ways as possible to ask for assistance and help Search & Rescue determine our location. << I think each pilot should be able to make that decision himself or herself. >> Of course, this is a political statement not an aviation safety statement of fact. But given human nature, mandates are not always bad. Sort of like forced automobile liability insurance. Tom Kuffel ------------------------------------------------------------------------------------- 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.