HID Lights and Radio Noise

I have the CreativAir HID landing lights in my wing tips and have noticed a small amount of white noise on both radios (GNS 430W and SL-40) when the lights are on. The white noise remains even after the HIDs have warmed up. Any thoughts on how I can stop the white noise? Bill from CreativAir had no suggestions.

RFI to ant or pwr inputs

Usually, RFI gets into a radio either via the antenna or the power input. Wiring to other attached peripherals is a possibility, but far less likely. Could try unplug antenna and see if noise still there (I assume you hear it on receive). If so, the usual remedy would be to better isolate the source, or protect the affected device, reroute wiring, check shield grounds, etc.. If gone with antenna disconnected, then obviously it's the antenna location, connections, and/or the noise source must be lessened. I know there's different kinds of HID lights and some are supposedly far worse with RFI generation than others. One debate on shielded line, i.e. to strobes, etc., is do you ground at the likely source end of RFI or at the other end only, i.e. the power supply. Get into the same debate re field line to an alternator. Staying away from that discussion.

Where are your antennas Jason? I have a wingtip antenna for my #2 Comm, with HID lights from Duckworks in the tips and if the lights are on, the #2 Comm is completely trashed. it's just something I manage operationally. If you have fuselage antennas, well, then you're on an RFI hunt as Link talked about...

Paul

Ironflight said:

Where are your antennas Jason? I have a wingtip antenna for my #2 Comm, with HID lights from Duckworks in the tips and if the lights are on, the #2 Comm is completely trashed. it's just something I manage operationally. If you have fuselage antennas, well, then you're on an RFI hunt as Link talked about...

Paul

Click to expand...

Does your Duckworks system use a D1S bulb or some other automotive kit bulb and have shielded cables from Ballast to bulb. It should be easy to tell if shielded or not by looking at both ends of the cable and how it interfaces to the ballast and bulb. Is it a Philips brand Ballast, or other brand ballast? What brand of ballast and bulb? Duckworks used a Philips brand ballast for a few years.

If using high quality components with proper shielding and installed optimally, these issues should not be unless installed very close to an antenna.

After I get some clarifications (details) I can make some suggestions. We must first determine if it is radiated or conducted "noise." You can power the ballasts off of an independent battery to isolate the problem. This will help determine if the noise is coming through your wires (conducted) or transmitted (radiated).

HID noise

Steve here from Planelights

Sorry for not being very active on VAF, I have a hard time participating in a forum if we are not a paying advertiser on the site. Now we have the ad a set up, so let me try to answer your questions:






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Paul,

It sounds like you have our MR16 set purchased from Duckworks. You shouldn't be getting that much(if any) interference. The MR16's are just about the "cleanest" system we sell. Check out this page:

http://www.planelights.com/index.php?id=702

How are your lights wired? How close is the ballast to the antenna? Is it on both sides or is the comm 2 antenna on one side(wing) only? We have had many sets of the MR16's installed next to "tape" antenna's(comm and nav) in wingtips with no problems. You will always have a little bit of noise with any HID light, doesn't matter if it's a D2S or D1S bulb. An HID bulb is a big spark gap generator, but it is very controllable. I am leaning toward something broke or loose causing that much noise. Let me know and we'll get this figured out. Feel free to call, #'s on the website, I am more than happy to send you a replacement to try.

Thanks
Steve
www.planelights.com

flyboeing said:

You will always have a little bit of noise with any HID light, doesn't matter if it's a D2S or D1S bulb. An HID bulb is a big spark gap generator, but it is very controllable.

Click to expand...

Have to clarify the facts on these 2 statement. I have 3 of our 50 watt (higher power) HID units on my airplane and with all three on steady or pulsing, I get no sound anywhere, anytime, not even with the squelch way down. I never hear noise from the HID's in any mode of operation. I have no special line filters etc. in place either, std install.

HID generates a DC "spark" for a fraction of a second during the ignition cycle, after that a Metal Halide plasma is formed to carry the current, no more spark(s), just a constant flow of ~ 400Hz AC at ~85 VAC once warmed up.

D1S (igniter integrated to the bulb) is a superior system. NO HID system without shielded cables from ballast to bulb and Using an integrated bulb/igniter (D1S) will be as quiet.

Only D1S with shielded cables will pass the GM (General Motors) CISPR noise standards to prevent problems with RFI, EMI for the ECU and other computer controlled systems. This is also true for DO160E noise stds. which we have exceeded.

Paul--

Both my Com antennas are on the belly of my plane (right under the seat pans). I do have a marker beacon antenna in one wingtip and a Archer VOR in the other.



Jason

Duckworks or Creativair lights?

Did you say you have the Duckworks HID's or the HID's from Creativair? I thought you said in the original post they were from Creativair, but the other posts say Duckworks. Just curious in case there is a difference.

eurof2 said:

Did you say you have the Duckworks HID's or the HID's from Creativair? I thought you said in the original post they were from Creativair, but the other posts say Duckworks. Just curious in case there is a difference.

Click to expand...

Those are 2 different posters with similar problems purchased from 2 different sources.

flyboeing said:

How are your lights wired? How close is the ballast to the antenna? Is it on both sides or is the comm 2 antenna on one side(wing) only? We have had many sets of the MR16's installed next to "tape" antenna's(comm and nav) in wingtips with no problems. You will always have a little bit of noise with any HID light, doesn't matter if it's a D2S or D1S bulb. An HID bulb is a big spark gap generator, but it is very controllable. I am leaning toward something broke or loose causing that much noise. Let me know and we'll get this figured out. Feel free to call, #'s on the website, I am more than happy to send you a replacement to try.

Click to expand...

Steve - thanks for takign the time to comment!

Yes, it appears that my lights from Duckworks are your system. The bulbs themselves are mounted about the only way they can be done in a Creativair tip (I used to have their Halogens - pretty low light output), you can see in the picture how I mounted the power supplies.



They are grounded locally, and I have an Archer Comm antenna mounted in the tip, and grounded to the outboard rib as well. I have the identical setup in the other tip, except that the antenna is for Nav, and I have noticed no degradation in Nav reception with the lights on or of.

This hasn't been a high priority, so I haven't pursued it, but I am happy to see you posting here!

Paul

That looks like the same power supply I am using with the CreativAir HIDS... mounted about the same as well. However, I do not have com antennas in either tip.


Jason

jrouault said:

That looks like the same power supply I am using with the CreativAir HIDS... mounted about the same as well. However, I do not have com antennas in either tip.


Jason

Click to expand...

Try powering the HID(s) from a separate source (car battery). While HID(s) are on, see if you still have the same problem(s), if so filters in the power wires (either at the ballasts or the affected radios will not help). It is an RF (radiated) not a conducted noise problem in that case. When doing this test also isolate the ballast case from ground (the airframe).

When making this test, If operating the ballasts independent of the aircraft electrical system the problem either all or mostly goes away. The ballast is putting the noise onto the electrical buss, + - or both. Some times isolating the ballast case (metal housing) from ground can also help this. This way the ground wire is the ONLY grounding path (no ground loop is created).

One filter which should help or eliminate a buss conducted noise problem is available from ACS made by Lonestar, it is called the "Eliminator" ACS P/N 11-08055 or from many other sources LS P/N 122253-10A $110-$120 each depending on source. It can be located at the offender(s) or at the affected radio etc. It is limited to a 10 amp current flow.

In the end if its RF radiated, Cable shielding may be needed from ballast to igniter and igniter to bulb and greater distance from HID to antennas may be required. Just isolating the ballast case from ground may do the trick, so that the ballast neg power wire is the only grounding path.


Note: FAA DO160E testing requires both conducted and radiated noise stds be met. CISPR (automotive std.) testing also requires both types of noise be covered and the std minimums be met.

Thanks for the information Dan. When I get a chance, I will try as you suggest. Right now the white noise is not bothersome enough to make resolving this a priority. Flying my phase 1 hours is top on the list. I need to have all my flight testing done by the end of July so I can bring the plane to Glo Custom for paint.

Fixing the noise?

I'm just finishing up a Duck Works installation with the HID's in both wings and have a marker becon antenna in left wing tip and an Archer "J" nav antenna in the other (it serves as VOR, Glide Slope and FM antenna).

My question after reading all the posts is "what works to keep the noise out". I have a 530 and SL 40 for coms and with one antenna on top and the other on the bottom. I'm going to go out tomorrow and give it a try in the hangar. I'll let you know what happens either way.

Roger

RV-6 N200RH with 1000+ hours

Henderson, NV

flyboeing said:

It sounds like you have our MR16 set purchased from Duckworks. You shouldn't be getting that much(if any) interference. The MR16's are just about the "cleanest" system we sell.

Click to expand...

That's what I have in my -8. The MR16's significantly reduced the range of my wingtip Archer nav antenna. So much so that I removed it and went with a cat whisker nav antenna mounted on the fuselage belly back by the tailwheel. That antenna works GREAT, as does my belly mounted bent whip comm antenna. I get noise in the system when I first turn on the HID lights for less than 10 seconds as the light warms up. I have a wig wag controller installed as well, and I also occasionally get a 'crackle' of noise when in wig wag mode. I think that is caused by an occasional bulb misfire, or by electricity leakage to ground in the wires from the ballast to the bulbs. I wish that part of the system was a little more robust - a shielded cable or somehting similar.

My ballasts are mounted with stainless screws is a similar fashion to Paul's. I am re-doing my EFIS system and had thought about mounting the magnetometers in the outboard rib in the wingtip, but am a little worried to do so because of potential interference from the ballast and/or lights.

One other thing: my HID lighting systems are powered by a non shielded conductor, and are grounded to the airframe locally. When I install my new EFIS system, there will be a lot of rewiring going on, and I'll probably run shielded wiring out to the tips to try to eliminate any power wire interference (if there is any), and also run my grounds back to my main grounding block in the fuselage.

to shield or not to shield

trying to power up this thread again.

This is my setup: RV-8 with Two leading edge 50w HID lights (used for landing), and Two Wingtip Round LED lights, these two pulsating via WigWag (all five items are Duckworks).

I am almost about to close the wing, so my question is: for each different light setup, should the wire be shielded, or it doesn't really matter?

Thanks!

I have 50W MR16 HID systems in each wingtip. The ballast and starter look just like the pictures posted earlier.

In the beginning, they broke the squelch on both my 430 and SL40. I used a handheld radio to see how much RF was radiating (and try to determine the source). This was partially successful. The RF appeared to be coming from the igniter (the box in the leads from ballast to bulb).

I fabricated a grounded shield around the igniter with a wire and some aluminum foil. For me, it has reduced the RF just enough such that it stays under my squelch level after the arc is established.

I think it could be better. The next time I have the tips off, I will probably put on some more shielding, or maybe try the idea above about insulating the ballast from the airframe (my grounds go back to the firewall).

GOT IT!

Yaa Hoo!.
I fixed it for good. Found by accident.
As stated above, the aluminum foil faraday cage helped. I grounded it to the airframe with a wire. Still had noise but it was less. I had the right tip off, trying to figure out what to do next. I was using a handheld tuned to ATIS and wanding it around all the HID parts. I moved the harness and suddenly the noise dropped big time. A little inspection showed that the aluminum foil was touching the end rib. Ah ha!. My grounding wire is not doing the job! I firmly zip tied the foil covered box to the end rib so there was firm contact between the foil and the rib. Noise was gone as far as I could tell with the handheld.

Flew today and confirmed it. No squelch break and little to no hiss during receive/transmit. Tower said I was 5x5 and I could hear them very clearly.

Another long term nuisance squawk FIXED. The list is getting very short.

Now I will start doing some night flying.

Its been a year since my last post on my HIDs. I am finally doing some night flying in order to commute for work. I have gotten questions by the various ground controllers a few times asking what I was packing in the light department. Brings a smile to my face.

This is with the MR-16 jobbers in the wingtips. Works great, less filling.

Yeah, night landings with HIDs is almost like cheating.

I installed HID lights with my build and get a noise in my VOR antenna at the wing tip. I moved the power supply and wiring further away and it helped enough that I have lived with it. I run my lights on a Wig-Wag and the VOR reception would flash just like the lights when at 60 to 100 miles out.
However I have now lost my second power supply in 15 months so I am changing over to the Whelen LED.
Hopefully as bright and less noise.