RudiGreyling

RudiGreyling

Well Known Member
Hi Guys,

Just wanted to show my final wingtip lights:

rv_wingtip_light_01.jpg


LED's very bright and only 0.7 AMPS per wingtip
rv_wingtip_light_02.jpg


HID Xenon very bright and only 3 AMPS per wingtip
rv_wingtip_light_03.jpg


Let me start out to say, they are not perfect, but I am happy with my experiment, and going to keep them. You also will need to tinker with them and change a bit. It is not a buy and fit exercise!

Jeff was so kind as to send me a set of his Luxeon LED kits, Well I changed his kit a bit, cut a hole for the light and moved the LEDs around. http://www.jeffsrv-7a.com/ Thanks Jeff!!

Then I bought the cheap HID FOG lamp set from Harbour Freight http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=95058
95058.gif


Being fog lamps the spot was not what I needed, so I opened them up and changed the internal reflective mirror upside down, to get the reflection on the side I wanted. Below is how I mounted the Fog Lamps.
wing_lights_05.jpg


So what about Radio Frequency Interference? There is, but...read on!
I have not flown but the best test I could do in the garage is take the handheld radio and see what I get.

I turned on the handheld radio and increased the sensativity until I get RX from normal backround noise then I close it just a bit and enoughto get crispy clean channel without any RX showing up. I put the Radio 6 feet from the lights

Then I turned on the LED's and I get RX on the Radio 6 feet away. Turning the sensativity down by only a 1/4 turn and it goes away. The LED's Jeff send me has a current limiting regulator pack on, this current regulater produce some RFI, He told me via email I should get rid of the current regulator and fit a special resistor which I could not get hold of in South Africa yet. Anyone in USA want to send me 2 from Radio Shack please ;-)

I was more concerned over the HID's. They have a ballast driver unit, and the light is produce by an ARC in the gas, and when one power them up you can hear them with the naked ear. Testing the HID the same way with the radio, starting on a very sensative but crisp and clean channel, I found that I had to turn the hand held sensativity down just past 1/4 turn (maybe 1/3 turn) to still get a clean channel again, no RX.

So I compared it to my Strobes that are suppose to be RFI and EMI compliant. The 'compliant' strobes also emit RFI with the radio on the most sensative setting, closing it 1/8 turn cleans up the strobes noise.

So if you want to tinker and willing to turn your radio sensativity slightly down, go for it! Just remember I have not flown yet, but that is what home building is all about, Experimenting. Your milage may vary, but these were my findings so far.

Good luck,
Regards
Rudi
 
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Rudi,

Nicely done. Sorry to play 20 questions, but I'm sure I'm the first of many.

Do you have any photos of the insides of the HID lights?

I'm interested in the reflector mod. Any pictures of the beam pattern?

I've heard HIDs tend to emit RFI during start up, and tend to quiet down after a couple of minutes. Did you do your RFI testing after they were warm?

Finally, from what I've seen the lights look like they use a H3 type base, would it be possible to pull the lamps out of the HID fog lights and install them in a Duckworks reflector?

Thanks,
Paige
 
Hi Paige,
I'll try and answer in line to your quote...

PaigeHoffart said:
Rudi,

Nicely done. Sorry to play 20 questions, but I'm sure I'm the first of many.

Do you have any photos of the insides of the HID lights?
I'm interested in the reflector mod. Any pictures of the beam pattern?
--> Sorry no picture of what you need, but in essenence the fog lights as Standard make a 180 degree pattern down mounted to the bottom of a car, so if you fit it sideways to a wingtip standard you only get one side lighted up inboard or outboard of your lamp. So it was a simple case of just removing the blocking bar in the reflector to get a better SPOT if you know what I mean.

I've heard HIDs tend to emit RFI during start up, and tend to quiet down after a couple of minutes. Did you do your RFI testing after they were warm?
--> On startup they are a bit more noisy, for 5 seconds or so and then settle down, but I only ran my test for about 2 minutes. I don't know if get even better after 2 minutes, but like I said not much much more than the RFI/EMI compliant strobes.

Finally, from what I've seen the lights look like they use a H3 type base, would it be possible to pull the lamps out of the HID fog lights and install them in a Duckworks reflector?
--> Sorry I haven't seen the Duckworks lights up close and personal so I don't have experience on them.

Thanks,
Paige
Click to expand...

My Pleasure,
Regards
Rudi
 
Thoughts.....

I have a similar setup to Rudi that I have been flying for almost 2 years.

I made LED Navs that I run with big current limiting resistors and have never had any noise on my SL-40. I run them all the time with my APRS tracker.

My Homebrew HID from an audi A4 is fit into a duckworks mount and reflector. It works well and I get noise for the 1st 10 secs on ballast startup, then it is dead quiet.

I have looked at the HF light kit and might put it in for a taxi/rec light setup to replace the M16 halogens I currently have in my tips.

Great work Rudi!!
 
Rudi,

The constant current drivers require a capacitor across the power input wires for noise control. The directions for these units state to apply a 220uF 50V polarized capacitor across the incoming power supply lines.

Did you do this? If not, I would recommend trying this before going to the simple voltage drop/current limiting resistor. The constant current driver will give you the best color and brightness over various operating conditions and will not produce a ton of heat like the resistor will.

The only advantage to the resistor/led combo is that it is a totally passive system that has no possiblility of producing any noise and it is cheaper than the driver and capacitor.

Just make sure you get the polarity right on the cap or you will make a really effective firecracker.:eek:
 
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If concerned about noise and you use a large capacitor to solve it (i.e. 220 uF electrolytic), I recommend placing a smaller ceramic capacitor (maybe .1 uF, 100V) in parallel with it. At RF frequencies, most electrolytic capacitors become inductive, which essentially means they stop filtering RF noise and may even serve to boost the noise. The small ceramic capacitor will continue to filter the higher frequency noise well into the RF freqencies we are concerned about.
 
Hi Rvators,

Someone asked me about the beam patterns and strenght of my modified Fog lamp HID's, so I'll post the comparive results below for all to see.

The digital camera was set to manual, and the comparison photos were taken with the exact same camera settings to show the difference:

TEST 1: Distance 4 meters, garage door 2m x 2m
HID:
beam_1.jpg


50W 12 degree Spot lamp:
beam_2.jpg


TEST 2: Distance 1 meter, wooden square blocks +/- 350x350 mm
HID:
beam_3.jpg


50W 12 Degree Spot lamp:
beam_4.jpg


Comparison:
The modified HID fog lamps gives a long Oval beam, with lots of surrounding light, very bright
The 50W 12 Degree Spot, makes a nice round beam, not very bright.

My opinion:
My modified Fog Lamp HID is bright enough to be used as a landing light, AND gives enough surrounding light to serve as a taxi light, so no need to aim 1 wingtip as taxi and one as landing light, meaning you get double the power and utility in both compared to other systems ;-)

Not recommending it to others, but if you want to try you can, I am happy with my experiment.

PS: I have not one further RFI testing since I do not have the CAPS yet, once I do I will comment again.

Regards,
Rudi
 
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Rudi,
Thanks for the update. The lights look great! Later I may do some experimenting with replacing my 100w Ductworks bulbs.

Brian,
Does the 220 uf capacitor have to be polarized? The manual I have and the reference Rudi has in his post shows a normal capacitor. Thanks
 
Rockyjs said:
Brian,
Does the 220 uf capacitor have to be polarized? The manual I have and the reference Rudi has in his post shows a normal capacitor. Thanks
Click to expand...


Either will work, the non polarized will likely be larger. That symbol in that PDF is a symbol for a polarized cap just without the + symbol which some people use and some do not. If you use a polarized, just make sure to get the polarity correct or it will explode after a few minutes of on time.
 
Excelent Workmanship Rudi

Thanks for the post and pictures, I keep thinking I'll finish my wing tips and along comes your creation, which is almost exactly what I'm planning on.

Look forward to any additional comments ideas.
 
Hi Guys,

Well the whole airplane is assembled, test flight in 2 or 3 weeks, but I thought I report back, ready to fly all instruments and lights installed in the airplane

The HID's produce almost no noise after heating up, With the tail down (RV7) I get enough surrounding light to serve as taxi light as well. They are supper bright!

The LEDs with the 2 caps and the powerpuck produce a lot of radio noise. I need some resistors instead of the power puck. Can't find the ones I need in SA (Somebody in the USA please PM me to ship me 2 non inductive 8ohm 20watt resistors ASAP PLEASE!) http://www.radioshack.com/product/index.jsp?productId=2062288

My strobes produce some noise, over the aircraft radio I need to see if I can eliminate that.

Shows what experiments outside the aircraft produce is not always the same when you hook everything up inside the aircraft on the same power source!

Regards
Rudi
 
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Rudi,

Did you try Jeff's suggestion as well or just the bigger cap? If you did not try his idea, it may be worth a go at it because the benefits of the constant current source are great.

Also, what configuration are you planning to use for that resistor size?

There is a calculator here that makes finding the best value for a passive resistor easy for people that do not want to do the calculations.

The problem is that most reds have a lower voltage drop than the cyan ones.

http://www.ledsupply.com/reca.php


Jeff R said:
If concerned about noise and you use a large capacitor to solve it (i.e. 220 uF electrolytic), I recommend placing a smaller ceramic capacitor (maybe .1 uF, 100V) in parallel with it. At RF frequencies, most electrolytic capacitors become inductive, which essentially means they stop filtering RF noise and may even serve to boost the noise. The small ceramic capacitor will continue to filter the higher frequency noise well into the RF freqencies we are concerned about.
Click to expand...

RudiGreyling said:
Hi Guys,

Well the whole airplane is assembled, test flight in 2 or 3 weeks, but I thought I report back, ready to fly all instruments and lights installed in the airplane

The HID's produce almost no noise after heating up, With the tail down (RV7) I get enough surrounding light to serve as taxi light as well. They are supper bright!

The LEDs with the 2 caps and the powerpuck produce a lot of radio noise. I need some resistors instead of the power puck. Can't find the ones I need in SA (Somebody in the USA please PM me to ship me 2 non inductive 8ohm 20watt resistors ASAP PLEASE!) http://www.radioshack.com/product/index.jsp?productId=2062288

My strobes produce some noise, over the aircraft radio I need to see if I can eliminate that.

Shows what experiments outside the aircraft produce is not always the same when you hook everything up inside the aircraft on the same power source!

Regards
Rudi
Click to expand...
 
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frankh said:
Now can one use HID's as wigwags??

Frank
Click to expand...

My understanding is no. Something about the internal construction of the bulb and ignitor.
I plan to use one of these for a taxi light but will stay with a traditional lamp for Wig-wag.
 
You can wig wag with HID's...

You can wig wag with HID's, but the wig wag controller is different. Duckworks has a controller that you can use.

If you have any other questions, I am sure Don at Duckworks would be more than happy to help.
 
Brantel said:
Rudi,

Did you try Jeff's suggestion as well or just the bigger cap? If you did not try his idea, it may be worth a go at it because the benefits of the constant current source are great. <SNIP>
Click to expand...

Yip, 2 caps 220uf and .1 uf in parrallel with the 700Mah Powerpuck.
I can only get normal resistors here in SA, not the non-inductive type.
Anyone know the difference?
Maybe someone has better experience with other constant current drivers, I need 700mA, but I don't want the RFI!

Regards
Rudi
 
Inductive vs. Non-Inductive

The difference is in the construction. There is no such thing as a perfect resistor.

An inductor is essentially a coil of wire. They're primarily used for RF type electronics either as a part of a tuned circuit, or to block the flow of RF as a choke.

Wire wound resistors present both resistance and inductance. For DC this doesn't matter, for RF this is a big no-no. Carbon composition resistors are basically a chunk of graphite...lots of resistance, very little inductance.

Another difference between wire wound and carbon resistors is how they behave when they heat up. Carbon has a negative temperature coefficient; so when it heats up, the resistance value actually decreases (causing more current flow and more heat). Wire wound or metal resistors have a positive temperature coefficient.


I'm not sure why a LED ballast resistor would have to be non-inductive.

Paige
 
Rudi,

I know your most likely tired of fooling with that driver but I do feel that they can work in an aircraft with radio's given the right combo of filter is found. I did like you and tested mine with a handheld and saw no problems but since I don't have a complete aircraft to test them in, that has left me with no way to do trial and error. I want the driver to succeed because of the fact that the constant current source is the best for the LED's for long life, consistent color and brightness and lower heat generation. The resistor is going to put off excess heat.

Some of these bigger power resistors are wire wound inside. If they had high currents going thru them and were next to something that would be impacted by the inducive field or if they were to be used in a circuit that was critical of induction, it would be bad.

That being said, your application is a simple current limiting circuit by dropping the excess voltage accross the resistor, a totally passive circuit. It should not matter one way or the other in your case.

I used the BuckPuck. Not sure if it would perform better or not. The only way to know is to try it on your airplane.

Another thing you could try Rudi is to run the power leads thru a ferrite core a couple times as close to the driver as possible. These things block RF very well. You may have some of these on old computer cables or power cords that you are no longer using. You could cut them out and use them or they should be locally available at an electronic supply store.

beads.gif


RudiGreyling said:
Yip, 2 caps 220uf and .1 uf in parrallel with the 700Mah Powerpuck.
I can only get normal resistors here in SA, not the non-inductive type.
Anyone know the difference?
Maybe someone has better experience with other constant current drivers, I need 700mA, but I don't want the RFI!

Regards
Rudi
Click to expand...
 
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HI Guys,

Thanks for the explanations, I can get some normal resistors locally so I might try them.

I managed to get some of the ferrite rings locally, just waiting for them to ship it to me, I'll try that first, before taking the Powerpuck out.

Brian I am using the standard Luxdrive Powerpuck 700ma unit and it is giving me RFI once connected to the airplane source.

Regards
Rudi
 
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Brian,

That is exactly who I got them from, (great minds think alike) they are shipping out to me today. Hope to get it before the weekend to try them out.

I am getting both types the bead type and the clipon type.
I am going to use the bead type close to the LED's and the clip on at the back of the Radio and Intercom.

Rudi
 
Good deal Rudi,

Thats even better because MGL claims they have selected theirs to have selected them for good RF choking in the airband range.

If that does not work, I give up... Take the powerpuck out and smash it with a hammer!

Let us know how it goes!


RudiGreyling said:
Brian,

That is exactly who I got them from, (great minds think alike) they are shipping out to me today. Hope to get it before the weekend to try them out.

I am getting both types the bead type and the clipon type.
I am going to use the bead type close to the LED's and the clip on at the back of the Radio and Intercom.

Rudi
Click to expand...
 
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Another thought...

Rudy,

One more experiment you might want to try if you haven't already is to power the LED's from a separate DC source. This would tell you if the interference is radiated or getting into your system via the power lines. I'd try connecting the separate power source directly to the driver right at the wing tip with short wires (i.e. don't use the wires running through the wing). Use shielded wire if you have some. If the problem goes away you know the interference is from the power lines.

I'd then power the LED's with the separate source using the wires running in the wings. If the problem returns it means the power lines are radiating the RF. The ferite beads may fix this or you may need shielded wire. If the problem does not return with the separate source using the wing wires, my guess would be a grounding issue. I have never been very good at tracking down grounding problems. I just remember a wire that looks like a short at DC, doesn't look like a short at RF. So short wire runs are best. Braided cable is better for making sure ground at DC is also ground at RF.

Good luck. I am going this route as well soon. So, I look forward to hearing your results.
 
apatti said:
Rudy,

One more experiment you might want to try if you haven't already is to power the LED's from a separate DC source. This would tell you if the interference is radiated or getting into your system via the power lines. <SNIP>
Click to expand...

Hi Tony, I have done it and tested it that way, if you read some of the earlier posts I have made. I think it is a bit of BOTH Radiated and via power lines.

Anycase see the full update I will post below...

Regards
Rudi
 
Hi Guys,

OK the final update on this Project now that I am flying...

I fitted the choke beads on the LED's with the Powerpucks still in tact and 2 more chokes at the back of the Radio and Intercom. The result was that the Audible noise on the radio went away BUT there was still some NON audible noise (let's call it White noise for not having a better word) on the system that limited the Radios receiption range.

What I mean is that I could get good Radio receiption from far away sources, but the second I turned the LED's on with Chokes and powerpuck, those far away radio sources went quite, not picked up, but no audible noise was on the system. When I turned the LED's OFF the far away radio sources was picked up again and clear.

So I took out the Chokes and the Power puck and fitted Normal 20Watt Carbon resistors just before the LED's which I chose for a supply voltage of 13.8 Volts to get the correct voltage drop for the LED's amp rating. (Remember RED and GREEN has different Voltage drops in the Luxeons). I could not get the exact RESISTORS so you get the one closest but slightly higer rated.

The Result now is that there is NO noise, no Audible and No white noise either. Far away radio transmisions are received clear no matter if the LED's are On or OFF. The LED's are only slightly less bright than running the Powerpuck, but still plenty bright over any candascent bulb.

Discovering the White non audible noise syndrome, I decided to re-check my HID lights. If you remember I said the audible noise go away as soon as they heat up? Well there is some white non audible noise also on them, after they heat up, but very very little compared to the LED's. I only have to touch the sensativity knob on the radio to pick up that far away radio transmisions on the ground with the HID's ON.

Now that I am flying I am very happy with my experiment, one does not even notice a difference in the radio performance with the HID's on or off, or with the LED's on or off.

I hope this sheds some light on the subject for some future experimenters.
Good luck with your experiments, and I hope you get good results with yours.

Regards
Rudi
 
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Hummmmmmm

Powerpucks.....? I belive they are called "Ferrite Beads". Avail everywhere inc radio shack.
 
Powerpucks are a constant current LED driver. The choke he referenced is a Ferrite Bead. The ones from Radio Shack may or may not be the proper material or size to attenuate RF signals in the airband.

Sticky1 said:
Powerpucks.....? I belive they are called "Ferrite Beads". Avail everywhere inc radio shack.
Click to expand...
 
Hummmmmmm

One of these days I'll learn how to read and then I might read all the posts instead of scanning them....:eek:
 
I've got the same problem that Rudi had. Lots of Interference on my VHF radios while running my LED Nav lights.

Rudi,
Did you ever test the Ferrite Beads only on the LED power supply end? I'm wondering if the beads on the the radio/intercom side caused a VHF signal attenuation that dropped the reception of far away stations.

Brian,
I believe you tested your LED setup with a separate source of power on a bench test. Did you ever try it on ships power?

I'm going to do some testing tomorrow and pull the led lights out of the aircraft. I have confirmed that my handheld radio is also getting blasted, when my nav lights are on so I'm assuming the Power Pucks are the culprit. I'll also call the supplier to see if they may have a solution. I may attempt to wrap the power supply in aluminum foil and see if that helps shield some of the stray trons.

Rocky
 
I just got off the phone with LED Supply where I purchased all my components. I was told the power supplies are very noisy. They recommended placing a .1uf ceramic capacitor on the OUTPUT side between the LED - and + leads. They said placing the power supply in a metal box may also help with shielding.

Rudi,
I reread your post and you already answered my question, sorry.
 
If you try the extra cap on the output and the metal box, let us know how it goes.

I cannot test mine with a real radio and ship power yet.

The easiest thing to do is just go with the resistors but I would like to find a good way to use the constant current drivers without too much complication or added weight.

Here is what I would try if I had the time and needed them soon:

1. On each array I would put 2 caps 220uf and .1 uF in parrallel with the drivers input leads
2. Another .1uF cap on the output leads
3. A ferrite bead on the input and output leads
4. Put all of this stuff in a small aluminum project box from Rat Shack with flying leads sticking out of it and ground that box. Should be able to fit this in a small rectangular box like this:

http://www.radioshack.com/sm-aluminum-project-enclosure--pi-2062217.html

pRS1C-2160124w345.jpg


Keep in mind that all of this is just me putting my knowledge of electronics in motion to attempt a low cost/weight solution at helping prevent the RF noise radiation off of these things. Try this at your own risk because there is no guarantee it will work. RF noise is a pain sometimes.
I talked via email to the engineer that designed these drivers and he told me that there was no effort put into making them RF quiet but instead making them small was the goal. He said most people do not use them as discrete components but instead as a part of a more elaborate circuit which would have the RF suppression built into the overall design.

Shame you can't buy a quiet one for slightly more money.

In the end we all may be back to using just the resistor which is cheap and easy. I just like the constant current driver for it's benefits like consistent brightness over time, cool running, small size ect. The resistor is harder to mount, creates a ton of heat and wastes ship power.
 
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I really like this design... ie the mirror plexi, led navs and the HID landing light in the wingtip... is there not a company that manufactures such a kit or am I stuck making my own?
 
LED RFI continues

Bad News!

Like Rudi, I tried to eliminate the RFI that my Buck Puck power supplies put out, but haven't found a reasonable solution. The side I am "experimenting" with is the Cyan K2 LEDs which have had some LEDs fail. I have never had a problem with the Red K2 stars, but I'm inclined now to believe that the power supply on the Cyan side is bad, at least I hope so. It is much noisier than the other power supply. I'm going to replace the power supplies with resistors.

I have the same setup as Brian 2 parallel 3 series (6 LEDs per side)

It looks like I can use a 4.7 ohm 2W resistor on each series string for the Cyan leds (3.6v voltage drop) and a 5.6 ohm 2W resistor on each series string for the Red (3.4v). This assumes a 14 volt supply voltage and 700ma current.
 
Oh well at least you tried Rocky.

I think I read somewhere that Jeff is recommending people ditch the constant current power supplies as well. Jeff if I am wrong, please forgive me.

It would be nice if there was an off the shelf driver that did not produce so much RF noise. Does not seem to be the case so I guess we will all settle with resistors in the end.

I just don't have the time to spend on developing a better driver solution. bigger fish to fry in this adventure of building a plane.
 
Hi Brian,
I'm interested in seeing what Jim Weir comes up with for a power supply in his next Kitplanes article on LEDs. Like everyone, I hate using the resistors and just wasting energy and adding more heat out there. The nice thing is in normal VFR cruise I'm only seeing about 23 amps total draw, so with my 60A system I've got lots of overhead. I'm waiting on a response about my Cyan K2 failures. As you know K2 stars weren't originally available in Cyan. I hope the power supply is the culprit, but at $7.50 each It's getting old replacing them. The strange thing is I haven't been using the NAV lights due to the RFI issues just me strobes. I found the last failed LED in the center position of one of the series runs. I'm up to about 27 hours in phase I and it is time to get the NAV light issues resolved.
 
I don't subscribe to that mag but please let me know what he does. I know there is an answer out there somewhere and yes a resistor works but if we can do better for cheap why not.

I ended up using Luxeon III in the cyan instead of the K2's for those because like you said, when I built mine, they were not making cyan K2's yet. Have not had any of these fail at this time but I have not ran them for more than a few hours at a time.

How is your heat sinking on that side? I would hope to think that it is the driver killing them.
 
I know it's of little consolation to those of you who are doing all the R&D and building your LED nav lights, but my Skybright "storebought" LED nav lights have had a few LED failures. Just thought you might like to know that some of the units that are for sale as completed nav lights still don't have all the bugs worked out of them.

Keep up the great work, folks. I'm watching intently to see how best to go about making LED strobes...
 
I bought these for the wings.
http://www.strobe.com/component/pag...id=0&option=com_virtuemart&Itemid=32&vmcchk=1

I also have a Kunzelman LED/tail strobe tube and and nova quickstrobe (12watt) single power supply. Compared the two and the LED is brighter, both subjectively and when using a very old camera light meter. Except when measuring to either side (where the LEDs are not pointing), at a range of 10 ft. No strict scientific testing here, just a garage gee whiz.
 
Bob


I haven't installed them yet, but I can't see any potential problems. The heat sink is only 6 inches long and made of 1/64 anodized aluminum, highly flexible. I have only had them on for 10 minutes or so, but in that time the sink never felt hot. Comes with 9ft of wire and no power supply to buy. They are not saving any $$ unless you count down the road in replacement tubes, but I really really like them. Even wiring a button in the cockpit to be able to change the flash pattern.
 
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guys, if you could do me a favor and give me a rundown on the LEDs that you're currently using, SPECIFIC luxeon model/current rating/color that you're using, I'm going to see if I can't get a good quiet constant current supply designed and prototyped. It's been on my list of things to look into for awhile, but it sounds like there's enough interest now to make it worth bringing to the forefront.

I have a Honeywell design engineer on my side to help with this, so I really think that if I can get input from you guys here as to what the performance goals are, we can come up with something nice. The only reason I haven't pursued this on my own yet is I'm not far enough along to know which LEDs I intend to use! If I can get some data points on the decisions everyone else has already made, we can design a driver which will meet those goals. Let me know asap!
 
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