Radio static w/LED’s

[NewValker]

I changed out the halogen driving lights for LED’s last winter. Same Kury billet chrome housings, just went LED’s. They are 50 watt equivalent, 500 lumens, 12 volt, 8 watt, rated for indoor/outdoor use. They are wired from battery with fuse in line.

Yesterday I used the radio for the first time this year, and with the driving lights on I get nasty static. Can barely hear the music over it. Shut the lights off, radio is perfect. iPod is not affected by lights at all. No CB on bike.

I do have an after market rubber antenna in place of OEM, this has been on bike since the first time I drove into my garage and the tip smashed the 2 bulbs in the ceiling light...

Static does not change with RPMs & it happens on all stations.

Anyone run across this before? Any & all-ideas welcome,
Craig

[Ramie]

Can cause interference.

http://betterautomotivelighting.com/2014/12/31/how-to-remove-radio-interference-using-ferrite-coils-for-hid-and-led-headlights/

[DGS65]

While a coil can help it is usually a bad ground on one of the devices that causes this issue.
I would see it you can at least run a temporary wire directly the battery ground to the radio and see if the problem goes away if so then find a better ground for the radio.  Does the radio have a light that turns on with the lights in question like a back light for the radio.
Back in the day I used to install stereos in cars,  hunting down issues like this were never fun but usually not to difficult to find.   The last resort is the coil you may actually correct the problem during the installation of said coil

Let us know what you find.  Led light were not around when I was doing this but there were other sources of noise like alternators.  usually the was mostly an AM issue for some reason.

[Valkyrie0002]

I have this issue on my Wrangler from my front aux. lights, the rears did not do this.  My Aux lights are wired direct to battery and have separate ground and the wires do no get near the radio.  I read that ferrite core snap-on rings would eliminate the static so I put them on the positive feed and ground but the static did not decrease.

[WintrSol]

I have this issue on my Wrangler from my front aux. lights, the rears did not do this.  My Aux lights are wired direct to battery and have separate ground and the wires do no get near the radio.  I read that ferrite core snap-on rings would eliminate the static so I put them on the positive feed and ground but the static did not decrease.

Ferrite beads and coils only help when the EMI is conducted through the wires, not radiated through the air. If the noise is conducted to the wires behind the LED drivers, then a ferrite as close to the driver as physically possible can reduce. Otherwise, Faraday shielding is the solution for radiated EMI, if you can't stop the source from radiating through the wires. Going through the connections to the bulbs, polishing contacts with DeoxIt, may help reduce it, but it the LED drivers are radiating directly, you have to make a shield with copper or aluminum screening and ground it. I wouldn't use something like foil, because of the possible heat problems.

[NewValker]

Wow, quite the education...never heard of this stuff.
Will check grounds and if still there go find some ferrite beads.
Thanks for the responses,
Craig

[Bagger John - #3785]

The main problem with a lot of the high-intensity LED lights is the scheme by which they're supplied power and dimmed.

Almost all use something known as pulse-width modulation. That is, the voltage sent to the lights is constant (battery voltage or near it) but the duty cycle is controlled as the function of a square wave...where the "On" portion can be anywhere from 0 to 100%.

In a constant-brilliance arrangement, some OEMs favor LEDs which are being run at or over their maximum values...they keep the power dissipation factor within specs by means of a PWM controller.

Square waves generate harmonics and hash all through the radio spectrum. It's a bad way to do things in terms of engineering but the approach is more cost effective than a linear (bypass regulator) controller scheme, which is why they're employed in so many applications.

I'm looking into "quieting" a set of Clearwater lights down so I can use my bike's CB with them. All the usual bypassing tricks won't work with these, so out comes the portable spectrum analyzer and other test gear...

[WintrSol]

Better designed controllers use filtered trapezoidal waves, instead of square; they also have shielding. Of course, they cost a bit more than the cheaper square-wave controllers.

[Steel cowboy]

Here is an example of what is being said. As a back up aid for my pick up I installed 2 4x4 off road LED lights below the rear bumper. When I put the truck in reverse the LEDs come on with the backup lights ( I hooked them to the center pin on the round trailer plug). The back up camera catches the pulsing of the LEDs but if you look in the side mirror your eye sees just solid lighting. Weird to see, but that's the pulsing. You can use your smart phone camera to catch the effect too.

[NewValker]

Thanks for that example Steel Cowboy.
That explains why when I took a pic of my last bike’s odometer at 100,000 miles it was pulsating on the phone face, but not to my eyes.
Craig

[NewValker]

Well, I finally got around to fixing the static problem.
I called Dan at Radiodan.com. Told him my problem, and he proceeded to make my eyes glaze over.
Turns out he says I need RFI Chokes on the wire to each light.
Ok, minimum order is 5 of them, with shipping totaled 17 bucks.
Put 1 on each and no static! He said 2 might be needed on each but 1 did the job.
If anyone else has these issues I highly recommend Radiodan.com
Craig