AeroElectric-List Digest Archive

Wed 08/01/12


Total Messages Posted: 17



Today's Message Index:
----------------------
 
     1. 06:03 AM - Re: Re: Latching Relay Redux (Robert L. Nuckolls, III)
     2. 06:27 AM - Re: Re: Using LEDs in Series (Robert L. Nuckolls, III)
     3. 06:34 AM - Re: What guage wire for alternator to bus bar (Robert L. Nuckolls, III)
     4. 08:22 AM - Re: Re: Latching Relay Redux (Ken)
     5. 10:32 AM - Re: Re: Latching Relay Redux (Robert L. Nuckolls, III)
     6. 12:30 PM - Re: Using LEDs in Series (Robert L. Nuckolls, III)
     7. 02:59 PM - PM Alternator filter Capacitor - best practices (John Loram)
     8. 03:19 PM - Re: PM Alternator filter Capacitor - best practices (Harley)
     9. 03:23 PM - Re: PM Alternator filter Capacitor - best practices (Robert L. Nuckolls, III)
    10. 04:47 PM - Re: PM Alternator filter Capacitor - best practices (John Loram)
    11. 06:14 PM - Re: Re: Using LEDs in Series (mapratherid)
    12. 07:17 PM - Re: PM Alternator filter Capacitor - best practices (Robert L. Nuckolls, III)
    13. 07:44 PM - Re: Re: Using LEDs in Series (Robert L. Nuckolls, III)
    14. 08:19 PM - Re: PM Alternator filter Capacitor - best practices (John Loram)
    15. 08:33 PM - Re: Re: Latching Relay Redux (Robert L. Nuckolls, III)
    16. 11:01 PM - Official AeroElectric-List FAQ (Frequently Asked Questions) (Matt Dralle)
    17. 11:05 PM - Official AeroElectric-List Usage Guidelines (Matt Dralle)
 
 
 


Message 1


  • INDEX
  • Back to Main INDEX
  • NEXT
  • Skip to NEXT Message
  • LIST
  • Reply to LIST Regarding this Message
  • SENDER
  • Reply to SENDER Regarding this Message
    Time: 06:03:18 AM PST US
    From: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>
    Subject: Re: Latching Relay Redux
    At 09:07 PM 7/30/2012, you wrote: > >I received this email today from Chuck (quoted below) in reference >to my circuit "Contactor PWM.pdf " to reduce contactor holding current. >http://forums.matronics.com/download.php?id=32370 > > > Hello Joe > > I built the circuit with one change. I replaced R1 with an > adjustable 0-25k ohm pot. Works great, just dial in the PWM for the > right duty cycle with R1 for the particular contactor being used. > > Thanks Chuck I recommend that the power saving duty cycle be set for not less than 50%. This cuts average voltage to contactor by 50% . . . hence average current by 50% and total power dissipated by 75%. While a 12v contactor will stay energized at voltages of 2v or below, you want to make sure that the contactor stays closed down to battery end of life at 10.5 volts or so. 50% at 14 volts with alternator running gives you 7 volts to hold the contactor . . . 10.5 translates to 5.25 volts or thereabouts . . . probably as low as you want to go. 75% reduction in lost energy is pretty substantial if you're in a battery-only operational mode . . . or struggling to make the most of an 8A alternator. Bob . . . Bob . . .


    Message 2


  • INDEX
  • Back to Main INDEX
  • PREVIOUS
  • Skip to PREVIOUS Message
  • NEXT
  • Skip to NEXT Message
  • LIST
  • Reply to LIST Regarding this Message
  • SENDER
  • Reply to SENDER Regarding this Message
    Time: 06:27:21 AM PST US
    From: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>
    Subject: Re: Using LEDs in Series
    At 09:58 PM 7/30/2012, you wrote: >Therein lies another problem, Eric. For a switching regulator >(digital) that is "noise free with really good design," you say that >it involves knowing what frequency spectrum you can use for >switching ... something that won't interfere. Switching regulators are ubiquitous and definitely here to stay. ALL of the accessories that trumpet 10-30 volt supply inputs are fitted with such power supplies. Operating frequency for such supplies is never 'selected' to be compatible with the operating environment. It's selected as a trade-off for for the components selected to achieve maximum efficiency at rated load. After design goals for efficiency are achieved, then careful board layout for controlling aperture area (radiation concerns) and good management of RF grounds (conduction concerns) and dv/dt limiting (both concerns) will minimize any necessary filtering and shielding to meet DO-160 emissions limits. Anyone who has done this exercise a couple of times will never again be surprised in the lab with failure of a new design to meet emissions limits. It's like learning to bake cakes. After my first few passes through the vibration immunity testing, I never again shook a component of a board . . . it's that 'learning curve' thingy. The filter I crafted for the BuckPucks was a brute force endeavor to fix a problem in systems that were already under construction and parts were on hand. The filter may be more than was really necessary . . . but it proved to be adequate to the task. A detailed study in the RFI lab might show that a simpler filter would do . . . but given the small volume of sales for this particular LED drive solution, it hardly justifies the expense of a finely tuned development effort. The BuckPuck was never intended for use in an aircraft EMC environment else it would not have been built that way. Some of the HID lamp supplies I've played with are similarly burdened with EMC issues for aircraft. That doesn't mean that any of these devices were "poorly designed", it only means that the customer base for thousands of units don't care that the device going into their boat, motorcycle or hot-rod is unsuited to airplanes. In the OBAM aviation world, we are a primo filter for searching out and identifying the best that folks know how to do. But it's a fine demonstration of the need for caveat emptor . . . give it a try in low risk experiments and report findings to the group. If a short-fall in performance is noted, then try something else . . . or modify the product (such as the filter board for the BuckPucks). In any case, the ultimate goodness of the device and the system in fits is up to us and NOT the designer of the device who probably never envisioned his work product going into an airplane . . . and would probably rather that it did not. It used to be that a phone call to Gates about v-belts had to be made in 'disguise' . . . if you mentioned that you were working on an airplane, the standard vociferous response was "our products are not intended for use on aircraft" . . . i.e. "you're on your own my friend". Bob . . .


    Message 3


  • INDEX
  • Back to Main INDEX
  • PREVIOUS
  • Skip to PREVIOUS Message
  • NEXT
  • Skip to NEXT Message
  • LIST
  • Reply to LIST Regarding this Message
  • SENDER
  • Reply to SENDER Regarding this Message
    Time: 06:34:11 AM PST US
    From: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>
    Subject: Re: What guage wire for alternator to bus bar
    At 07:04 AM 7/31/2012, you wrote: sorry ( i am a newbie to this forum ) if this is already answered else where, but i would like to know the minimum gauge wire i should use for a 60amp alternator (15V) to the Bus bar which is 5ft away. In normal operation max current draw in flight would be 12 amps ( landing lights , nav lights, radio, transponder, solenoids) 6AWG would be good, 4AWG welding cable is readily available, inexpensive and would be better. In addition, (and this may seem like a silly idea), but I actually want to limit the maximum current that could go into my lithium Ion Phosphate battery immediately after start up to say 10 amps, how would I go about this ? Currently it is drawing max amps out of the alternator for the rotation speed (1200 rpm) for a few minutes, and I think this was the reason for my alternator drive coupling slipping. We need more information here. Your alternator drive system should be designed to function at the alternator's rated output. In other words, if it slips under some conditions of loading, then the answer is to fix the drive system, not reduce the load. Where does the 1200 rpm number come from . . . prop RPM? What's the alternator RPM at this time? Bob . . .


    Message 4


  • INDEX
  • Back to Main INDEX
  • PREVIOUS
  • Skip to PREVIOUS Message
  • NEXT
  • Skip to NEXT Message
  • LIST
  • Reply to LIST Regarding this Message
  • SENDER
  • Reply to SENDER Regarding this Message
    Time: 08:22:19 AM PST US
    From: Ken <klehman@albedo.net>
    Subject: Re: Latching Relay Redux
    Is that 75% power reduction correct?? I would have guessed that a 50% duty cycle gave full voltage and full current for 50% of the time in a pulsed resistance circuit resulting in a 50% power reduction. Not sure about an inductive coil contactor though. Just asking but intuitively I would not have averaged the voltage and applied the I squared power calculation to this. Ken On 01/08/2012 9:02 AM, Robert L. Nuckolls, III wrote: > <nuckolls.bob@aeroelectric.com> > > At 09:07 PM 7/30/2012, you wrote: >> <fran4sew@banyanol.com> >> >> I received this email today from Chuck (quoted below) in reference to >> my circuit "Contactor PWM.pdf " to reduce contactor holding current. >> http://forums.matronics.com/download.php?id=32370 >> >> > Hello Joe >> > I built the circuit with one change. I replaced R1 with an >> adjustable 0-25k ohm pot. Works great, just dial in the PWM for the >> right duty cycle with R1 for the particular contactor being used. >> > Thanks Chuck > > I recommend that the power saving duty cycle > be set for not less than 50%. This cuts average > voltage to contactor by 50% . . . hence average > current by 50% and total power dissipated by > 75%. > > While a 12v contactor will stay energized at > voltages of 2v or below, you want to make sure > that the contactor stays closed down to battery > end of life at 10.5 volts or so. 50% at 14 volts > with alternator running gives you 7 volts to hold > the contactor . . . 10.5 translates to 5.25 volts > or thereabouts . . . probably as low as you want > to go. 75% reduction in lost energy is pretty > substantial if you're in a battery-only operational > mode . . . or struggling to make the most of an > 8A alternator. > > Bob . . . > >


    Message 5


  • INDEX
  • Back to Main INDEX
  • PREVIOUS
  • Skip to PREVIOUS Message
  • NEXT
  • Skip to NEXT Message
  • LIST
  • Reply to LIST Regarding this Message
  • SENDER
  • Reply to SENDER Regarding this Message
    Time: 10:32:09 AM PST US
    From: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>
    Subject: Re: Latching Relay Redux
    At 10:20 AM 8/1/2012, you wrote: Is that 75% power reduction correct?? I would have guessed that a 50% duty cycle gave full voltage and full current for 50% of the time in a pulsed resistance circuit resulting in a 50% power reduction. Not sure about an inductive coil contactor though. Just asking but intuitively I would not have averaged the voltage and applied the I squared power calculation to this. ----------- Excellent question . . . and yes, consideration of contactor inductance paralleled with a diode is critical to the analysis. When to the bench and set this up: Emacs! This test setup produced the following data: Emacs! If I go to 100% duty cycle, this El Cheeso, Stancore/RBM contactor draws 0.9 amps 14.6 volts. Dynamically, the coil current (Yellow trace) shows some ripple at the switching frequency but averages just under 0.5 Amp. In the mean time, the power supply is showing a load of just 0.21 amps or about 25% of the full-on current draw. If I put a 15 ohm resistor in place of the\ contactor, the 100% current goes to the expected 1 amp. At 50% duty cycle, the peak current is still 1 amp with average current falling to the predicted 0.5A . . . hence 50% duty cycle produces only 50% reduction in power in the resistive circuit. The L/R time constant of the inductive circuit prevents achievement of full current during limited on-time. The diode prevents current from falling to zero during off-time. After one hour, the outside temperature of the contactor was not too hot to sustained touch . . . Waayyy cooler than contactor operatied at 100%. Bob . . .


    Message 6


  • INDEX
  • Back to Main INDEX
  • PREVIOUS
  • Skip to PREVIOUS Message
  • NEXT
  • Skip to NEXT Message
  • LIST
  • Reply to LIST Regarding this Message
  • SENDER
  • Reply to SENDER Regarding this Message
    Time: 12:30:49 PM PST US
    From: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>
    Subject: Re: Using LEDs in Series
    I have been experimenting with a product available off eBay that offers 300, .05 x .05 LED's mounted to a 3/8" wide x 16 foot flexible etched circuit strip. http://tinyurl.com/c33w25o The leds are wired in paralleled series-clusters of 3 devices and a 150 ohm resistor. Here's a 2-cluster segment of this product . . . Emacs! You can cut the strip every three devices and attach new power leads at the solder pads visible in the photo. I'm going to be using about 80 feet of this product in my kitchen to put double rows of ceiling accent lighting high up, double rows to replace recessed canister lights over the counters and a third twin-row installation under the cabinets for work lighting. The double-rows will be wired in series to run off 24 volt supplies in the walls. My present lighting is fraught with hot-spots from 11 different fixtures with no accent lighting on a budget of about 700 watts. The working end of my kitchen will be nicely lighted for both appearance and working illumination on a power budget of about 175 watts total. This technique produces very wide-angle illumination that is virtually shadow free. The strips are fitted with peel and stick adhesive. I'm going to use 3/4" wide strips of Formica to assemble one- piece lighting assemblies that make it easy to get the rows installed straight while laying on my back under a cabinet. The light output from these devices is very good. I suspect that one could put a single strip of this product on the under side of a glare shield and get more than enough light . . . with devices easily dimmed. Due to the series wiring of three, 3-volt devices, you would want to control dimming with a series resistance or an adjustable current supply like a Buck-Puck. Ten of these clusters would give you about 30 leds and a max bright current draw of 300 mA. A constant voltage dimmer like B&C sells COULD be modified to have minimum brightness occur at 9 volts instead of the present 4 volts. In any case, This product offers a host of illumination opportunities not the least of which is your airplane. Bob . . .


    Message 7


  • INDEX
  • Back to Main INDEX
  • PREVIOUS
  • Skip to PREVIOUS Message
  • NEXT
  • Skip to NEXT Message
  • LIST
  • Reply to LIST Regarding this Message
  • SENDER
  • Reply to SENDER Regarding this Message
    Time: 02:59:14 PM PST US
    From: "John Loram" <johnl@loram.org>
    Subject: PM Alternator filter Capacitor - best practices
    What would be considered best practice for installation of the large electrolytic capacitor used to filter the output of a PM alternator: Mount it on the hot side of the firewall and protect the occupants Mount it on the cool side of the firewall and protect the capacitor Would appreciate any speculations, -john-


    Message 8


  • INDEX
  • Back to Main INDEX
  • PREVIOUS
  • Skip to PREVIOUS Message
  • NEXT
  • Skip to NEXT Message
  • LIST
  • Reply to LIST Regarding this Message
  • SENDER
  • Reply to SENDER Regarding this Message
    Time: 03:19:09 PM PST US
    From: Harley <harley@AgelessWings.com>
    Subject: Re: PM Alternator filter Capacitor - best practices
    Evenin', John, Good timing for this question! Just finished installing mine last week! And no speculation in my case... I put mine inside, behind the passenger's head (Long EZ...pusher engine not as bad as it sounds....a headrest pad and a couple of canopy braces protect the passenger from the electronics on the inside of the firewall) mainly because the installation instructions with the B&C alternator specifically said NOT to mount the cap on the engine side of the firewall because of the heat there! Guess the passenger is less important than the alternator!;-) Harley Dixon Long EZ N28EZ ----------------------------------------------------------------- On 8/1/2012 5:57 PM, John Loram wrote: > What would be considered best practice for installation of the > large electrolytic capacitor used to filter the output of a PM > alternator: > Mount it on the hot side of the firewall and protect the occupants > Mount it on the cool side of the firewall and protect the capacitor > Would appreciate any speculations, -john- > * > *


    Message 9


  • INDEX
  • Back to Main INDEX
  • PREVIOUS
  • Skip to PREVIOUS Message
  • NEXT
  • Skip to NEXT Message
  • LIST
  • Reply to LIST Regarding this Message
  • SENDER
  • Reply to SENDER Regarding this Message
    Time: 03:23:12 PM PST US
    From: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>
    Subject: Re: PM Alternator filter Capacitor - best practices
    At 04:57 PM 8/1/2012, you wrote: >What would be considered best practice for installation of the large >electrolytic capacitor used to filter the output of a PM alternator: > >Mount it on the hot side of the firewall and protect the occupants > >Mount it on the cool side of the firewall and protect the capacitor > >Would appreciate any speculations, -john- It's utility is limited. See in particular, the second page of http://tinyurl.com/cz7ekrf even with no capacitor, the noises are well under Mil-STD-704 limits for DC power systems. So mounting it 'cool' probably bodes best for service life and has little effect on system performance. Bob . . .


    Message 10


  • INDEX
  • Back to Main INDEX
  • PREVIOUS
  • Skip to PREVIOUS Message
  • NEXT
  • Skip to NEXT Message
  • LIST
  • Reply to LIST Regarding this Message
  • SENDER
  • Reply to SENDER Regarding this Message
    Time: 04:47:10 PM PST US
    From: "John Loram" <johnl@loram.org>
    Subject: PM Alternator filter Capacitor - best practices
    Hmmmm... so why do we use this cap? -john- _____ From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Robert L. Nuckolls, III Sent: Wednesday, August 01, 2012 3:23 PM Subject: Re: AeroElectric-List: PM Alternator filter Capacitor - best practices At 04:57 PM 8/1/2012, you wrote: What would be considered best practice for installation of the large electrolytic capacitor used to filter the output of a PM alternator: Mount it on the hot side of the firewall and protect the occupants Mount it on the cool side of the firewall and protect the capacitor Would appreciate any speculations, -john- It's utility is limited. See in particular, the second page of http://tinyurl.com/cz7ekrf even with no capacitor, the noises are well under Mil-STD-704 limits for DC power systems. So mounting it 'cool' probably bodes best for service life and has little effect on system performance. Bob . . .


    Message 11


  • INDEX
  • Back to Main INDEX
  • PREVIOUS
  • Skip to PREVIOUS Message
  • NEXT
  • Skip to NEXT Message
  • LIST
  • Reply to LIST Regarding this Message
  • SENDER
  • Reply to SENDER Regarding this Message
    Time: 06:14:52 PM PST US
    Subject: Re: Using LEDs in Series
    From: mapratherid <mapratherid@gmail.com>
    This looks pretty cool Bob. But I'm picky about color temp. Any idea what Ke lvin color you'll end up with? Regards, Matt- On Aug 1, 2012, at 1:29 PM, "Robert L. Nuckolls, III" <nuckolls.bob@aeroelec tric.com> wrote: > I have been experimenting with a product available > off eBay that offers 300, .05 x .05 LED's mounted > to a 3/8" wide x 16 foot flexible etched circuit > strip. > > http://tinyurl.com/c33w25o > > The leds are wired in paralleled series-clusters of > 3 devices and a 150 ohm resistor. Here's a 2-cluster > segment of this product . . . > > <1839fa0.jpg> > > You can cut the strip every three devices and attach new > power leads at the solder pads visible in the photo. > > I'm going to be using about 80 feet of this product in > my kitchen to put double rows of ceiling accent lighting high up, > double rows to replace recessed canister lights over the > counters and a third twin-row installation under the cabinets > for work lighting. The double-rows will be wired in series to run > off 24 volt supplies in the walls. My present lighting > is fraught with hot-spots from 11 different fixtures with > no accent lighting on a budget of about 700 watts. The working > end of my kitchen will be nicely lighted for both appearance > and working illumination on a power budget of about 175 > watts total. This technique produces very wide-angle > illumination that is virtually shadow free. > > The strips are fitted with peel and stick adhesive. I'm > going to use 3/4" wide strips of Formica to assemble one- > piece lighting assemblies that make it easy to get the > rows installed straight while laying on my back under > a cabinet. > > The light output from these devices is very good. I suspect > that one could put a single strip of this product on the > under side of a glare shield and get more than enough > light . . . with devices easily dimmed. Due to the > series wiring of three, 3-volt devices, you would want > to control dimming with a series resistance or an > adjustable current supply like a Buck-Puck. Ten of > these clusters would give you about 30 leds and a max > bright current draw of 300 mA. A constant voltage > dimmer like B&C sells COULD be modified to have minimum > brightness occur at 9 volts instead of the present > 4 volts. In any case, This product offers a host of > illumination opportunities not the least of which is > your airplane. > > Bob . . .


    Message 12


  • INDEX
  • Back to Main INDEX
  • PREVIOUS
  • Skip to PREVIOUS Message
  • NEXT
  • Skip to NEXT Message
  • LIST
  • Reply to LIST Regarding this Message
  • SENDER
  • Reply to SENDER Regarding this Message
    Time: 07:17:12 PM PST US
    From: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>
    Subject: PM Alternator filter Capacitor - best practices
    At 06:45 PM 8/1/2012, you wrote: >Hmmmm... so why do we use this cap? > Now you done it . . . let's see if I recall. I think I first saw it used on a power distribution diagrams for some Rotax powered ultra-lights back when I first started working in OBAM aviation. Shucks . . . the rectifiers of AC to DC power supplies had filter capacitors on them . . . why not the rectified ac output of a PM alternator? The idea was attractive, only the numbers were poorly understood. If you push 1 amp into a 1 Farad capacitor, you get a 1 volt per second rate of rise in voltage. 10 amps is 10 volts per second. Okay, how about a 1 microfarad capacitor? The rise is 1 million times faster or 10M volts per second. Now make the capacitor 20,000 times bigger and the voltage rise rate drops by a factor of 20K or 500 volts per second. Okay, the ripple period in the traces I published for 4000 rpm was 7.5 milliseconds. .0075 x 500 = 3.75 volts is the best ripple reduction we might expect from 20KF on a 10A machine. As you can see from page 2 trace, the pk-pk excursions are already below 400 mv. already 10X better than what we might expect with but with no capacitor. To cut that to say, 40 mV (nice anc quiet comparatively) we'd need a capacitor 100 times 20,000 or 2 Farads. I was startled by the test results with the SD-8 on B&C's alternator stand. There was little or no observable effect at ripple frequency for adding the capacitor. Yeah, we can buy such a critter but it's big, heavy, expensive and goes toward an unnecessary refinement of the system. We know that a 3-phase alternator has about 5% pk-pk ripple (0.75 volts on a 15v system) plus transients. How many Farads would it take to smooth say a 100A machine? The single phase PM alternators like the SD-8 are obviously worse but battery alone combined with loads at or near max ratings have more smoothing effects than the capacitor. Given the physical impracticality of seeing such pristine power, complimentary standards and design goals were adopted to say (in Mil- STD-704) that a 28v system can have 1 VRMS (3+ volts pk-pk) noise from 1 to 5K Hertz and tapering off each side. http://tinyurl.com/78kwfk8 1/2 that value for a 14v system. The complimentary DO-160 design goals tell us to EXPECT this kind of trash on the bus and design to live with it. The capacitor doesn't hurt anything and if you have a particularly bad set of rectifier switching transients (or similar fast rise stuff elsewhere in the system, the 20-20K computer grade capacitor will reduce the effects of that stimulus. Suffice it to say that MOST pilots now flying such capacitors on their PM alternator installations would notice nothing from the cockpit if that capacitor were removed. Radios and audio systems need really clean power and the qualified designer provides smoothing internally. Emacs! Our audio isolation amplifier design uses the LM317 to provide a smooth source of +8 volts to run the circuitry. As a general rule, the kinds of stimulus that benefits from any sort of bus voltage filtering is fast-rise transients at a ripple-current rate. Folks mistakenly believe their inductor/capacitor or just a capacitor is bypassing AUDIO frequency energy when in fact, it's high frequency (fast transients) at the audio rate. As the numbers above suggest, there's no practical way to filter alternator ripple from the bus. The snow-mobile engines with lighting coils converted to electrical system alternators may well have benefited from the use of such capacitors . . . depends on vulnerabilities inherent in their electro-whizzies. Our electro-whizzies are suited by design to live in the world of trashy busses. This is why switchmode power supplies can be so small when delivering outputs in the tens of amps . . . their operating frequencies (hence ripple frequency) is quite high which allows smaller capacitors and inductors to do the same degree of smoothing. You can leave the cap out and see if you hear any alternator whine in the audio . . . odds are that you will not. Bob . . .


    Message 13


  • INDEX
  • Back to Main INDEX
  • PREVIOUS
  • Skip to PREVIOUS Message
  • NEXT
  • Skip to NEXT Message
  • LIST
  • Reply to LIST Regarding this Message
  • SENDER
  • Reply to SENDER Regarding this Message
    Time: 07:44:09 PM PST US
    From: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>
    Subject: Re: Using LEDs in Series
    At 08:13 PM 8/1/2012, you wrote: >This looks pretty cool Bob. But I'm picky about color temp. Any idea >what Kelvin color you'll end up with? You can select for cool, pure, or warm white colors when you order. Given the cheapness of excess brightness for you can probably do some shading with theater lighting gels. I had to match some lighting colors in incandescent lamps about 25 years ago at Videmation. A local theater supply store had every color hue and density imaginable in gels for about $2 a sheet. We fiddled with the filters until we got it right. In my kitchen I'll be using the pure whites and letting colors reflected from surfaces set the mood. At Cessna, blue-white post lighting was a high dollar option for panel illumination. You could get the same thing by putting the appropriate gel over the lamps. Bob . . .


    Message 14


  • INDEX
  • Back to Main INDEX
  • PREVIOUS
  • Skip to PREVIOUS Message
  • NEXT
  • Skip to NEXT Message
  • LIST
  • Reply to LIST Regarding this Message
  • SENDER
  • Reply to SENDER Regarding this Message
    Time: 08:19:59 PM PST US
    From: "John Loram" <johnl@loram.org>
    Subject: PM Alternator filter Capacitor - best practices
    So we're not trying to control the bandwidth of the regulator loop with the cap? Does the battery do that? Guess I don't really know what the frequency response of a lead-acid battery is. Probably dependent on the state of charge and the condition of the battery. And the load varies all over the place, both real and imaginary components.... What would it look like with and without the cap if the battery were out of the loop? ... Scary! I'm running 3 phase (old Jab 3300). Once I get this thing fired up I'll run some tests and let you know what happens... Just thinking out loud, -john- p.s. ran into a message the other day that you wrote back in 2007. Said you worked for H.L Yoh as a civilian instructor in the early 60's... Same here! At the Naval ETA school on Treasure Island. Wasn't that fun. I learned more electronics in six months instructing those kids than four years of collage! _____ From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Robert L. Nuckolls, III Sent: Wednesday, August 01, 2012 7:11 PM Subject: RE: AeroElectric-List: PM Alternator filter Capacitor - best practices At 06:45 PM 8/1/2012, you wrote: Hmmmm... so why do we use this cap? Now you done it . . . let's see if I recall. I think I first saw it used on a power distribution diagrams for some Rotax powered ultra-lights back when I first started working in OBAM aviation. Shucks . . . the rectifiers of AC to DC power supplies had filter capacitors on them . . . why not the rectified ac output of a PM alternator? The idea was attractive, only the numbers were poorly understood. If you push 1 amp into a 1 Farad capacitor, you get a 1 volt per second rate of rise in voltage. 10 amps is 10 volts per second. Okay, how about a 1 microfarad capacitor? The rise is 1 million times faster or 10M volts per second. Now make the capacitor 20,000 times bigger and the voltage rise rate drops by a factor of 20K or 500 volts per second. Okay, the ripple period in the traces I published for 4000 rpm was 7.5 milliseconds. .0075 x 500 = 3.75 volts is the best ripple reduction we might expect from 20KF on a 10A machine. As you can see from page 2 trace, the pk-pk excursions are already below 400 mv. already 10X better than what we might expect with but with no capacitor. To cut that to say, 40 mV (nice anc quiet comparatively) we'd need a capacitor 100 times 20,000 or 2 Farads. I was startled by the test results with the SD-8 on B&C's alternator stand. There was little or no observable effect at ripple frequency for adding the capacitor. Yeah, we can buy such a critter but it's big, heavy, expensive and goes toward an unnecessary refinement of the system. We know that a 3-phase alternator has about 5% pk-pk ripple (0.75 volts on a 15v system) plus transients. How many Farads would it take to smooth say a 100A machine? The single phase PM alternators like the SD-8 are obviously worse but battery alone combined with loads at or near max ratings have more smoothing effects than the capacitor. Given the physical impracticality of seeing such pristine power, complimentary standards and design goals were adopted to say (in Mil- STD-704) that a 28v system can have 1 VRMS (3+ volts pk-pk) noise from 1 to 5K Hertz and tapering off each side. http://tinyurl.com/78kwfk8 1/2 that value for a 14v system. The complimentary DO-160 design goals tell us to EXPECT this kind of trash on the bus and design to live with it. The capacitor doesn't hurt anything and if you have a particularly bad set of rectifier switching transients (or similar fast rise stuff elsewhere in the system, the 20-20K computer grade capacitor will reduce the effects of that stimulus. Suffice it to say that MOST pilots now flying such capacitors on their PM alternator installations would notice nothing from the cockpit if that capacitor were removed. Radios and audio systems need really clean power and the qualified designer provides smoothing internally. Emacs! Our audio isolation amplifier design uses the LM317 to provide a smooth source of +8 volts to run the circuitry. As a general rule, the kinds of stimulus that benefits from any sort of bus voltage filtering is fast-rise transients at a ripple-current rate. Folks mistakenly believe their inductor/capacitor or just a capacitor is bypassing AUDIO frequency energy when in fact, it's high frequency (fast transients) at the audio rate. As the numbers above suggest, there's no practical way to filter alternator ripple from the bus. The snow-mobile engines with lighting coils converted to electrical system alternators may well have benefited from the use of such capacitors . . . depends on vulnerabilities inherent in their electro-whizzies. Our electro-whizzies are suited by design to live in the world of trashy busses. This is why switchmode power supplies can be so small when delivering outputs in the tens of amps . . . their operating frequencies (hence ripple frequency) is quite high which allows smaller capacitors and inductors to do the same degree of smoothing. You can leave the cap out and see if you hear any alternator whine in the audio . . . odds are that you will not. Bob . . .


    Message 15


  • INDEX
  • Back to Main INDEX
  • PREVIOUS
  • Skip to PREVIOUS Message
  • NEXT
  • Skip to NEXT Message
  • LIST
  • Reply to LIST Regarding this Message
  • SENDER
  • Reply to SENDER Regarding this Message
    Time: 08:33:25 PM PST US
    From: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>
    Subject: Re: Latching Relay Redux
    At 12:30 PM 8/1/2012, you wrote: >At 10:20 AM 8/1/2012, you wrote: > >Is that 75% power reduction correct?? > >I would have guessed that a 50% duty cycle gave full voltage and >full current for 50% of the time in a pulsed resistance circuit >resulting in a 50% power reduction. Not sure about an inductive coil >contactor though. > >Just asking but intuitively I would not have averaged the voltage >and applied the I squared power calculation to this. >----------- P.S. just for grins, I thermocoupled the contactor and let it stabilize for over an hour. Got a 120 F shell at 50% duty cycle for a 40F rise. Let it run 100% duty cycle to stabilization and got a 180F shell temperature for a 100F rise. At that temperature, the 100% duty cycle current draw was down to .6 amps from the cold start at .9 amps. This copper temperature coefficient of resistance rise in coil accounts for the less than 4x temperature rise for 4x the dissipated power . . . This means that a cooler contactor uses the power you supply it more efficiently by running a lower winding resistance. I.e. ampere turns of magnetic flux that is more proportional to applied voltage because the coil is cooler. By the way, here's one approach to fabricating a "contactor cooler" . . . http://tinyurl.com/bolkoyc On power up, both capacitors are discharged. The 10uf holds down on the comparator pins 2,6 for about 100 milliseconds thus holding the output pin 3 HI, turning the FED on hard and energizing the contactor with full voltage. The 10uF charges up in 100-200 milliseconds thus allowing the 555 to 'hum' at about 200Hz and 50% duty cycle. The diode and RC network across the contactor coil should be mounted right to the contactor terminals. All other components can be remotely located but close proximity to contactor is best. Bob . . .


    Message 16


  • INDEX
  • Back to Main INDEX
  • PREVIOUS
  • Skip to PREVIOUS Message
  • NEXT
  • Skip to NEXT Message
  • LIST
  • Reply to LIST Regarding this Message
  • SENDER
  • Reply to SENDER Regarding this Message
    Time: 11:01:13 PM PST US
    From: Matt Dralle <dralle@matronics.com>
    Subject: Official AeroElectric-List FAQ (Frequently Asked Questions)
    Dear Listers, Please read over the AeroElectric-List Frequently Asked Questions (FAQ) below. The complete AeroElectric-List FAQ including the Usage Guidelines can be found at the following URL: http://www.matronics.com/FAQs/AeroElectric-List.FAQ.html Thank you, Matt Dralle Matronics Email List Administrator [ Note: This FAQ was designed to be displayed with a fixed width font such as Courier. Proportional fonts will cause display formatting errors. ] This FAQ can also be viewed in HTML online at the following address: http://www.matronics.com/FAQ/AeroElectric-List.htm ************************************************************ ******* LIST POLICIES AND FREQUENTLY ASKED QUESTIONS ******* ************************************************************ PLEASE READ. This document contains AeroElectric-List policies and information for new and old subscribers. Understanding the AeroElectric-List policies will minimize problems for the Administrator, and will help keep the AeroElectric-List running smoothly for all of us. ****************************************** *** Quick Start Guide to List Features *** ****************************************** There are many features available on the Matronics Email Lists and each one is described in detailed below. However, using the List Navigator you can quickly access the complete set of features available for this List. The List Navigator can be found at the following URL: http://www.matronics.com/Navigator?AeroElectric-List **************************************** *** How to Subscribe and Unsubscribe *** **************************************** Simply go to the Web Page shown below and enter your email address and select the List(s) that you wish to subscribe or unsubscribed from. You may also use the handy "Find" function to determine the exact syntax of your email address as it is subscribed to the List. Please see the complete instructions at the top of the Web Page for more information. The Subscribe/Unsubscribe web page is: http://www.matronics.com/subscribe Note that you will receive TWO conformation emails regarding your subsciption process. The first verifies that your subscription/unsubsciption request was received, and the second confirms that the process has been completed. You should receive the first email within a few minutes of your request. The second conformation will arrive in less than 24 hours. You cannot post until you receive the second conformation email message. ***************************** *** How to Post a Message *** ***************************** Send an email message to: aeroelectric-list@matronics.com Your message will be redistributed to everyone currently subscribed to the List. ***************************************************** *** SPAM Fighter - You Must be Subscribed to Post *** ***************************************************** When a new post is received by the system, the From: line of the message is checked and compared against the current subscription list. If the email address is found, the message is passed on to the List Processor. If the email address isn't found in the current list of subscribers, it is dumped. This serves to very effectively thwart 99% of the SPAM that gets posted to the Lists. Remember, however, that the syntax of your email address is very important with regard to the configuration of your email application such as Outlook or Eudora. For example, the following two email addresses may be functionally equivalent, but only one would pass the Matronics Email SPAM test depending on which was syntax was subscribed to the given List: smith@machine.domain.com smith@domain.com Either email address syntax is alright, just be sure that you configure your email application to match *exactly* the address you've subscibed to the List. ************************************** *** Enclosure Support on the Lists *** ************************************** Limited posting of enclosures such as pictures, documents, and spreadsheets is supported on the Lists. There are a number of restrictions, and these are detailed below. Please abide by the rules put forth regarding the content of enclosures. These are some of the features and limits of enclosures on the Matronics Lists: 1) Enclosures will only be posted to the Real Time version of the Lists. 2) Enclosures will NOT be included in the Daily Digest version of the Lists. 3) Enclosures WILL BE forwarded on to the BBS Forum Web site. 4) Enclosures will NOT be appended to the Archives. 5) Enclosures will NOT be available in the List Browse feature. 6) Only the following file types and extensions will be allowed: bmp doc dwg dxf gif jpg pdf png txt xls All other enclosures types will be rejected and email returned to sender. The enclosure types listed above are relatively safe from a virus standpoint and don't pose a particularly large security risk. 7) !! All incoming enclosures will be scanned for viruses prior to posting to the List. This is done in real time and will not slow down the process of posting the message !! Here are some rules for posting enclosures. Failure to abide by these rules could result in the removal of a subscriber's email address from the Lists. 1) Pay attention to what you are posting!! Make sure that the files you are enclosing aren't HUGE (greater that 1MB). Remember that there are still people checking they're email via dial up modem. If you post 30MB worth of pictures, you are placing an unnecessary burden on these folks and the rest of us, for that matter. 2) SCALE YOUR PICTURES DOWN!!! I don't want to see huge 3000 x 2000 pictures getting posted that are 3 or 4MB each. This is just unacceptable. Use a program such as Photoshop to scale the picture down to something on the order of 800 x 600 and try to keep the file size to less-than 200KB, preferably much less. Microsoft has a really awesome utility available for free that allows you to Right-Click on a picture in Explorer and automatically scale it down and resave it. This is a great utility - get it, use it! http://www.microsoft.com/windowsxp/downloads/powertoys/xppowertoys.mspx Look for the link "Image Resizer" 3) !! This would seem to go without saying, but I'll say it anyway. Do not post anything that would be considered offensive by your grandmother. And you know what I'm saying; I don't want to see anything even questionable. !! 4) REMEMBER THIS: If you post a 1MB enclosure to a List with 1000 members subscribed, your 1MB enclosure must be resent 1000 times amounting to 1MB X 1000 = 1 Gigabyte of network traffic!! BE CAREFUL and BE COURTEOUS! Also see the section below on the Matronics Photo and File Share where you can have your files and photos posted on the Matronics web server for long time viewing and availability. ******************* *** Digest Mode *** ******************* Each day, starting at 12 midnight PST US, a new 'digest' will be started. This digest will contain the same information that is currently appended to the archive file. It has all of the headers except for the "From:" and "Subject:" lines removed, and includes a message separator consisting of a line of underscores. Each day at 23:55 PST US, the day's messages as described above will be combined and sent as a single message to everyone on the digest email list. To subscribe to the digest list, use the same subscription web form described above, and just select the Digest version of the List. http://www.matronics.com/subscribe Note that you *can* be subscribed to both the realtime and digest versions of the List at the same time. This is perfectly acceptable. Now some caveats: * Messages sent to "aeroelectric-list-digest" will be forwarded to the standard email list. In other words, you cannot post messages only to the digest List. * If you are subscribed to both the regular List and the digest List, you will receive the realtime postings as well as the digest at the end of the day. * If you reply to the digest email, your message will be forwarded to the normal list associated with the digest. Important Note: Please change the subject line to reflect the topic of your response! Also, please *do not include all or most of the digest in your reply*. **************************** *** List Digest Browser *** **************************** An archive of all the List Digests can be found online in either plain text or HTML format. These archives contain the exact Digest that was posted to the Digest email list on the given day. The Digest Archives can be found at the following location: http://www.matronics.com/digest ***************************************** *** The "DO NOT ARCHIVE" Message Flag *** ***************************************** At times, your message may concern something that is revelent only to a very small number of persons or to a limited area, and you may not wish to archive it. In such a case, simply put the following phrase anywhere in the message: do not archive Your message will not be appended to the archive, but will be sent to List email distribution as normal. ********************************************** ***** READ THIS - Automatic Unsubscribes ***** ********************************************** Note that if your email address begins to cause problems such as bounced email, mailbox is filled, or any other errors, your address will be promptly removed from the List. If you discover that you are no longer receiving messages from the AeroElectric-List, go to the following Web page, and look for your email address and a possible reason for your removal. The Matronics Email List uses utility called the "Email Weasel" that automatically looks though the day's bounced email for addresses that caused problems due to common things like "user is unknown", "mailbox full", etc. If the Email Weasel removes your email address from the Lists you will find record of it at the following URL: http://www.matronics.com/unsubscribed If the problem listed on the web site above has been resolved, please feel free to resubscribe to the Lists of your choice. ******************************* *** List Member Information *** ******************************* If you have not done so already, please email me your phone numbers and paper mail address in the following format: smith@somehost.com Joe Smith 123 Airport Lane Tower, CA 91234-1234 098-765-1234 w 123-456-7890 h Please forward this information to the following email address: requests@matronics.com I have a file of such things, that I typically use to contact you when there are problems with your email address. The information will NOT be used for any other commercial purpose. **************************************** *** Realtime Web Email List Browsing *** **************************************** Recent messages posted to the AeroElectric-List are also made available on the Web for realtime browsing. Seven days worth of back postings are available with this feature. The messages can be sorted by Subject, Author, Date, or Message Thread. The Realtime List Browser indexes are updated twice per hour at xx:15 and xx:45. You can also reply to a message or start a new message directly from the List Browser Interface (coming soon). You do not have to be subscribed to the given list to use the List Browser Interface in view-mode. http://www.matronics.com/browselist/aeroelectric-list ******************************************* *** Web Forums Bulletin Board Interface *** ******************************************* A phpBB BBS web Forums front end is available for all AeroElectric-List content. content. The Forums contain all of the same content available via the email distribution and found on the various archive viewing formats such as the List Browse, etc. Any posts on the web Forums will be cross posted to the respective email List, and posts to the Email List will be cross posted to the web Forums. You may view all List content on the Forums without any special login. If you wish to post a message via the Web Forum interface, however, you will need to Register. This is a simple process that takes only a few minutes. A link to the Registration page can be found at the top of the main web Forums page. Note that registering on the Forum web site also enables you to send email posts to the Lists as well. You will also need to Subscribe to the respective Email List as described above to receive the Email Distribution of the List, however. The Matroincs Email List Web BBS Forums can be found at the following URL: http://forums.matronics.com ********************************* *** Matronics Email List Wiki *** ********************************* In an attempt to make it easy to store and find structured and often accessed information, Matronics has installed a Wiki at: http://wiki.matronics.com The Wiki allows individuals to create web pages to contain useful information for other users of the mailing lists and web site. Unlike an ordinary web page where the content needs to be submitted to Matronics for inclusion, the Wiki permits the users to construct their own pages and have them visible immediately. While constructing pages for the Wiki is not difficult, some may not be comfortable building pages. In that case, simply prepare the text and any images and email it to: wiki-support@matronics.com One of the volunteers on that list will take your submission and construct a Wiki page for you. Often someone produces a particularly useful posting in email one one of the Lists that would be of general interest. In that case Matronics may take that post and convert it into a Wiki page. ********************* *** List Archives *** ********************* A file containing of all of the previous postings to the AeroElectric-List is available on line. The archive file information is available via the Web and FTP in a number of forms. Each are briefly described below: * AeroElectric-List.FAQ - Latest version of the AeroElectric-List Frequently Asked Question page (this document). * AeroElectric-Archive.digest.complete - Complete file with most of the email header info removed and page breaks inserted between messages. * AeroElectric-Archive.digest.vol-?? - Same as the file above, but broken up into small sections that can more easily handled. * AeroElectric-Archive.digest.complete.zip - Same as the AeroElectric-Archive.digest.complete file above, but in PKZIP format. Use "binary" data transfer methods. * AeroElectric-Archive.digest.complete.Z - Same as the AeroElectric-Archive.digest.complete file above, but in UNIX compress format. Use "binary" data transfer methods. Download Via FTP ---------------- The archive file is available via anonymous FTP from ftp.matronics.com in the "/pub/Archives" directory. It is updated daily and can be found in a number of formats as described above. (All filenames are case sensitive.) ftp://ftp.matronics.com/pub/Archives Download Via Web ---------------- The archives are also available via a web listing. These can be found toward the bottom of the following web page: http://www.matronics.com/archives ****************************************** *** Complete List Web Archive Browsing *** ****************************************** All messages posted to the AeroElectric-List are also available using the Email List Archive Browsing feature. With this utility, all messages in the List are indexed, and individual sub-archives can be browsed. http://www.matronics.com/archive/archive-index.cgi?AeroElectric ***************************************** **** High-Speed Archive Search Engine *** ***************************************** You can use the custom, high-performance Matronics Email List Search Engine to quickly locate and browse any messages that have been posted to the List. The Engine allows the user to easily search any of the currently available List archives. http://www.matronics.com/search **************************** *** File and Photo Share *** **************************** With the Matronics Email List File and Photo Share you can share pictures and other data with members of the List without having to forward a copy of it to everyone. To share your Files and Photos, simply email them to: pictures@matronics.com !! ==> Please including the following information with each submission: 1) Email Lists that they are related to. 2) Your Full Name. 3) Your Email Address. 4) One line Subject description. 5) Multi-line, multi-paragraph description of topic. 6-x) One-line Description of each photo or file Prior to public availability of the files and photos, each will be scanned for viruses. Please also note that the process of making the files and photos available on the web site is a pseudo-manual process, and I try to process them every few days. Following the availability of the new Photoshare, an email message will be sent to the Email Lists enumerated in 1) above indicating that the new Share is available and what the direct URL to it is. For a current list of available Photoshares, have a look at the Main Index Page: http://www.matronics.com/photoshare ************************** *** List Archive CDROM *** ************************** A complete Matronics Email List Archive CD is available that contains all of the archives since the beginning of each of the Lists. The archives for all of the Lists are included on the CD along with a freeware search engine written by a list member. The CD is burned the day you order it and will contain archive received up to the last minute. They make great gifts! http://www.matronics.com/ArchiveCDROM ********************************** *** List Support Contributions *** ********************************** The Matronics Lists are run *completely* through the support of it members. You won't find any PopUpAds, flashing Banner ads, or any other form of annoying commercialism on either the Email Messages or the List web pages associated with the Matronics Email Lists. Every year during November I run a low-key, low-pressure "Fund Raiser" where, throughout the month, I ask List members to make a Contribution in any amount with which they are comfortable. I will often offer free gifts with certain contribution levels during the Fund Raiser to increase the participation. The gifts are usually donated by companies that are themselves List members. Your Contributions go directly to supporting the operation of the Lists including the high-speed, business-class Internet connection, server system hardware and software upgrades, and to partially offset the many many hours I spend running, maintaining, upgrading, and developing the variety of services found here. Generally Contributions range from $20 to $100 and are completely voluntary and non-compulsory. I ask only that if person enjoys the Lists and obtains value from them, that they make a Contribution of equal magnitude. Contributions are accepted throughout the year, and if you've just subscribed, feel free to make a Contribution when you've settled in. The website for making SSL Secure Contributions is listed below. There are a variety of payment methods including Visa and MasterCard, PayPal, and sending a personal check. If you enjoy and value the List, won't you make a Contribution today to support its continued operation? http://www.matronics.com/contributions Thank you! Matt Dralle Email List Administrator ****************************************************************************** AeroElectric-List Usage Guidelines ****************************************************************************** The following details the official Usage Guidelines for the AeroElectric-List. You are encouraged to read it carefully, and to abide by the rules therein. Failure to use the AeroElectric-List in the manner described below may result in the removal of the subscribers from the List. AeroElectric-List Policy Statement The purpose of the AeroElectric-List is to provide a forum of discussion for things related to this particular discussion group. The List's goals are to serve as an information resource to its members; to deliver high-quality content; to provide moral support; to foster camaraderie among its members; and to support safe operation. Reaching these goals requires the participation and cooperation of each and every member of the List. To this end, the following guidelines have been established: - Please keep all posts related to the List at some level. Do not submit posts concerning computer viruses, urban legends, random humor, long lost buddies' phone numbers, etc. etc. - THINK carefully before you write. Ask yourself if your post will be relevant to everyone. If you have to wonder about that, DON'T send it. - Remember that your post will be included for posterity in an archive that is growing in size at an extraordinary rate. Try to be concise and terse in your posts. Avoid overly wordy and lengthy posts and responses. - Keep your signature brief. Please include your name, email address, aircraft type/tail number, and geographic location. A short line about where you are in the building process is also nice. Avoid bulky signatures with character graphics; they consume unnecessary space in the archive. - DON'T post requests to the List for information when that info is easily obtainable from other widely available sources. Consult the web page or FAQ first. - If you want to respond to a post, DO keep the "Subject:" line of your response the same as that of the original post. This makes it easy to find threads in the archive. - When responding, NEVER quote the *entire* original post in your response. DO use lines from the original post to help "tune in" the reader to the topic at hand, but be selective. The impact that quoting the entire original post has on the size of the archive can not be overstated! - When the poster asks you to respond to him/her personally, DO NOT then go ahead and reply to the List. Be aware that clicking the "reply" button on your mail package does not necessarily send your response to the original poster. You might have to actively address your response with the original poster's email address. - DO NOT use the List to respond to a post unless you have something to add that is relevant and has a broad appeal. "Way to go!", "I agree", and "Congratulations" are all responses that are better sent to the original poster directly, rather than to the List at large. - When responding to others' posts, avoid the feeling that you need to comment on every last point in their posts, unless you can truly contribute something valuable. - Feel free to disagree with other viewpoints, BUT keep your tone polite and respectful. Don't make snide comments, personally attack other listers, or take the moral high ground on an obviously controversial issue. This will only cause a pointless debate that will hurt feelings, waste bandwidth and resolve nothing. - Occasional posts by vendors or individuals who are regularly subscribed to a given List are considered acceptable. Posts by List members promoting their respective products or items for sale should be of a friendly, informal nature, and should not resemble a typical SPAM message. The List isn't about commercialism, but is about sharing information and knowledge. This applies to everyone, including those who provide products to the entire community. Informal presentation and moderation should be the operatives with respect to advertising on the Lists. ------- [This is an automated posting.] do not archive


    Message 17


  • INDEX
  • Back to Main INDEX
  • PREVIOUS
  • Skip to PREVIOUS Message
  • NEXT
  • Skip to NEXT Message
  • LIST
  • Reply to LIST Regarding this Message
  • SENDER
  • Reply to SENDER Regarding this Message
    Time: 11:05:13 PM PST US
    From: Matt Dralle <dralle@matronics.com>
    Subject: Official AeroElectric-List Usage Guidelines
    Dear Listers, Please read over the AeroElectric-List Usage Guidelines below. The complete AeroElectric-List FAQ including these Usage Guidelines can be found at the following URL: http://www.matronics.com/FAQs/AeroElectric-List.FAQ.html Thank you, Matt Dralle Matronics Email List Administrator ****************************************************************************** AeroElectric-List Usage Guidelines ****************************************************************************** The following details the official Usage Guidelines for the AeroElectric-List. You are encouraged to read it carefully, and to abide by the rules therein. Failure to use the AeroElectric-List in the manner described below may result in the removal of the subscribers from the List. AeroElectric-List Policy Statement The purpose of the AeroElectric-List is to provide a forum of discussion for things related to this particular discussion group. The List's goals are to serve as an information resource to its members; to deliver high-quality content; to provide moral support; to foster camaraderie among its members; and to support safe operation. Reaching these goals requires the participation and cooperation of each and every member of the List. To this end, the following guidelines have been established: - Please keep all posts related to the List at some level. Do not submit posts concerning computer viruses, urban legends, random humor, long lost buddies' phone numbers, etc. etc. - THINK carefully before you write. Ask yourself if your post will be relevant to everyone. If you have to wonder about that, DON'T send it. - Remember that your post will be included for posterity in an archive that is growing in size at an extraordinary rate. Try to be concise and terse in your posts. Avoid overly wordy and lengthy posts and responses. - Keep your signature brief. Please include your name, email address, aircraft type/tail number, and geographic location. A short line about where you are in the building process is also nice. Avoid bulky signatures with character graphics; they consume unnecessary space in the archive. - DON'T post requests to the List for information when that info is easily obtainable from other widely available sources. Consult the web page or FAQ first. - If you want to respond to a post, DO keep the "Subject:" line of your response the same as that of the original post. This makes it easy to find threads in the archive. - When responding, NEVER quote the *entire* original post in your response. DO use lines from the original post to help "tune in" the reader to the topic at hand, but be selective. The impact that quoting the entire original post has on the size of the archive can not be overstated! - When the poster asks you to respond to him/her personally, DO NOT then go ahead and reply to the List. Be aware that clicking the "reply" button on your mail package does not necessarily send your response to the original poster. You might have to actively address your response with the original poster's email address. - DO NOT use the List to respond to a post unless you have something to add that is relevant and has a broad appeal. "Way to go!", "I agree", and "Congratulations" are all responses that are better sent to the original poster directly, rather than to the List at large. - When responding to others' posts, avoid the feeling that you need to comment on every last point in their posts, unless you can truly contribute something valuable. - Feel free to disagree with other viewpoints, BUT keep your tone polite and respectful. Don't make snide comments, personally attack other listers, or take the moral high ground on an obviously controversial issue. This will only cause a pointless debate that will hurt feelings, waste bandwidth and resolve nothing. - Occasional posts by vendors or individuals who are regularly subscribed to a given List are considered acceptable. Posts by List members promoting their respective products or items for sale should be of a friendly, informal nature, and should not resemble a typical SPAM message. The List isn't about commercialism, but is about sharing information and knowledge. This applies to everyone, including those who provide products to the entire community. Informal presentation and moderation should be the operatives with respect to advertising on the Lists. ------- [This is an automated posting.] do not archive




    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
  • 7-Day List Browse
  •   http://www.matronics.com/browse/aeroelectric-list
  • Browse AeroElectric-List 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.

    -- Please support this service by making your Contribution today! --