Off Road LED lights causing radio to cut out?

Site Notices

[ARCHIVED THREAD] - Off Road LED lights causing radio to cut out?

Posted: 7/24/2014 1:28:57 PM EDT

I finally got my FT-7900 installed and tuned. Works great, and I couldn't be happier with it! But last night I went for a drive and noticed that there was no talking going on, even though I knew a net should be taking place. I didn't think much of it, and kept driving. I stopped for a while and turned the truck off and suddenly the radio came to life! It was the usual 2130 chatting that I'm so used to hearing. Thinking maybe I was in a canyon before I reached in and turned the key back on to use the light bars to look around. As soon as they came on, the radio cut out. What could be causing this? I checked all the grounds, they are all separate and sturdy, all power connections are sturdy and tight. None of the wires from the lights cross over the coax or even any of the other power wires to the lights or radio.

Even on simplex it will kill the signal unless I'm really close, then it just converts to static with choppy audio. What did I do wrong? I'm at a loss.

Radio has constant power wiring, with the time out function at 30 minutes auto off.

Lights are wired to ignition power through a relay and then to the battery.

Doesn't matter if it's front, left, or right lights. All cut the radio out.

Posted: 7/24/2014 1:41:06 PM EDT

[#1]

Odds are the lights have a power supply that's got EMI issues. If you have another radio like a handheld,
turn it on and then turn on the lights, then move closer/farther away from them. My guess is you'll find
the lights are radiating a strong signal somewhere in the 2M band, or all across it.

Posted: 7/24/2014 2:43:15 PM EDT

[#2]

And I suppose there isn't a way to correct that problem without replacing each lights power supply, right?

Posted: 7/24/2014 3:28:16 PM EDT

[#3]

Quote History

Quoted:
And I suppose there isn't a way to correct that problem without replacing each lights power supply, right?

View Quote

Well... it depends. Ferrite beads might fix it if placed on the power leads right at the light, but no guarantee.

Also it'll depend on where the antenna is v. the lights. Worst case would be right next to them, best case would
be far away and the light power supply is in a metal housing, in which case the ferrites might accomplish something.

Edit: This is the critter you'd want to put on the power leads.

Posted: 7/24/2014 3:43:35 PM EDT

[#4]

Thanks for the help. Guess I'll have to go visit HRO and snag a few of those. The side lights are about two feet from the antenna. It's the front lights that will pose a problem, they are mere inches from the antenna. Guess I didn't do all my homework like I thought I did.

Posted: 7/24/2014 4:17:17 PM EDT

[#5]

Well, you can always live with it and know you can't radio and use lights at same time,
which would only be an issue when offroading at night I'd guess.

Try the beads, they might fix things. I'm genuinely surprised that lights made it out of
the factory with that level of RFI emissions, though. FCC would take a pretty dim
view of that, pardon the pun.

Posted: 7/24/2014 4:58:45 PM EDT

[#6]

my el-cheapo walgreens UBS/12volt adapter does the same thing

what kind of lights are they ?

regular 12volt halogens never gave me any RFI

Posted: 7/24/2014 5:07:07 PM EDT

[#7]

They are the newer style LED light bars. Hopefully the beads will correct it, I noticed it with my HT months ago when it would randomly stop on a channel and I'd hear static when the lights were on. Once I flipped em off, the radio would scan right past the channel.

Posted: 7/25/2014 3:06:28 PM EDT

[#8]

Which model in particular? I'm thinking about getting some... Now I'm not so sure.

Posted: 7/25/2014 4:53:31 PM EDT

[#9]

no issues with mine

Posted: 7/25/2014 7:16:42 PM EDT

[#10]

Quote History

Quoted:
They are the newer style LED light bars. Hopefully the beads will correct it, I noticed it with my HT months ago when it would randomly stop on a channel and I'd hear static when the lights were on. Once I flipped em off, the radio would scan right past the channel.

View Quote

A lot of those cheaper LED light bars are built in China. I'd be shocked if they WERE NOT putting off RF interference in some band. You just lucked out and it's putting off interference in your band.

Good luck, but I doubt you'll fix it without replacing the light bar.

<-- Halogens FTW.

Posted: 7/25/2014 11:38:36 PM EDT

[#11]

Quote History

Quoted:
And I suppose there isn't a way to correct that problem without replacing each lights power supply, right?

View Quote

You might open up one of the power supplies, and see what it has (or lacks) for filtering, particularly on the side that connects to the vehicle battery.

Chinese supplies tend to be real chinzy on the quantity and quality of the bypass caps they use - Often, adding a few quality caps will help quite a bit.

Another trick is to connect the lights directly to the vehicle battery, through their own dedicated wiring. The battery itself is a pretty decent filter, but only if the offending device uses a separate connection to it from any others used by interference-prone devices.

Posted: 7/26/2014 4:44:48 AM EDT

[#12]

that is a good point. those lights SHOULD be connected directly to the battery through a relay.

Posted: 7/26/2014 5:20:19 AM EDT

[#13]

Point of interest. My cheap china backup LEDs create all kind of when I throw my truck in reverse.

My Baja Designs LED bumper lights and LED light bar, produce no noise or interference.

Buy once, cry once.

Posted: 7/26/2014 7:10:28 AM EDT

[#14]

600.00 vs 120.00

i could live with some rf noise for that difference.

Posted: 7/26/2014 9:18:50 AM EDT

[#15]

I've got all LED's pointed forward on my Jeep. Everything is made in China…nothing radiates. Prior to the 11" light bar, I had a 2 KC Daylighters, and then I had 4 KC Slim Lites on the roof rack. I adapted the Daylighter's wiring.

The head lights are even LED…I still have problems with VHF/UHF QRM on several traffic lights, but no problems with the LED tail lights, LED head lights, LED reverse lights, or LED light bar.

Posted: 7/26/2014 6:48:43 PM EDT

[#16]

A couple more tricks:

1. Tightly twist the DC power wires, all the way from the light bar to the battery. This makes them "self-shielding", and can reduce the amount of RFI emitted by them.

2. Cut open some RG-8 coax, strip out the outer braid, and run your light bar's DC power wires through it. Ground it at the battery end.

Posted: 7/26/2014 6:59:26 PM EDT

[#17]

Quote History

Quoted:
<-- Halogens FTW.

View Quote

+1

When you stop and think about all the zillions of frequencies that you might operate on.....well, why waste time trying to filter out RFI, when, once you think you have it taken care of, you drop down to 15meters and find more.

make mine halogen

Posted: 7/26/2014 9:43:22 PM EDT

[#18]

I hope auxiliary HID lights don't cause the same problem.

I went with KC Daylighter HID for my roof lights.

Haven't ordered the led light bar for the bumper yet. Going with something around 12" for use when winching.

Haven't decided what I am going with for roof rack side lights or back up lights.Still have to fabricate a roof rack mount and the rear bumper, tire carrier, fuel can holder.

Posted: 7/27/2014 11:16:20 AM EDT

[#19]

Quote History

Quoted:
I hope auxiliary HID lights don't cause the same problem.

I went with KC Daylighter HID for my roof lights.

Haven't ordered the led light bar for the bumper yet. Going with something around 12" for use when winching.

Haven't decided what I am going with for roof rack side lights or back up lights.Still have to fabricate a roof rack mount and the rear bumper, tire carrier, fuel can holder.

View Quote

Aftermarket HID's are notorious for RF noise actually.

If you're going with HID's, look into these.
LED Headlight

I run them on my Cherokee with a Anytone mobile (we all know how not so great the squelch circuits are on Chinese radios) and I've yet to have a problem with them. They don't bug the CB in the same vehicle as well.

Posted: 7/28/2014 8:26:52 AM EDT

[#20]

Quote History

Quoted:
I hope auxiliary HID lights don't cause the same problem.

I went with KC Daylighter HID for my roof lights.

Haven't ordered the led light bar for the bumper yet. Going with something around 12" for use when winching.

Haven't decided what I am going with for roof rack side lights or back up lights.Still have to fabricate a roof rack mount and the rear bumper, tire carrier, fuel can holder.

View Quote

My aftermarket HIDs made 2m work impossible...went back to stock.

Posted: 7/29/2014 3:13:53 AM EDT

[#21]

Quote History

Quoted:

Aftermarket HID's are notorious for RF noise actually.

If you're going with HID's, look into these.
LED Headlight

I run them on my Cherokee with a Anytone mobile (we all know how not so great the squelch circuits are on Chinese radios) and I've yet to have a problem with them. They don't bug the CB in the same vehicle as well.

View Quote View All Quotes

View All Quotes

Quote History

Quoted:

Quoted:
I hope auxiliary HID lights don't cause the same problem.

I went with KC Daylighter HID for my roof lights.

Haven't ordered the led light bar for the bumper yet. Going with something around 12" for use when winching.

Haven't decided what I am going with for roof rack side lights or back up lights.Still have to fabricate a roof rack mount and the rear bumper, tire carrier, fuel can holder.

Aftermarket HID's are notorious for RF noise actually.

If you're going with HID's, look into these.
LED Headlight

I run them on my Cherokee with a Anytone mobile (we all know how not so great the squelch circuits are on Chinese radios) and I've yet to have a problem with them. They don't bug the CB in the same vehicle as well.

I have decided to just use halogens for my headlights for now. The exposed fan on the back of the LED leaves me with doubts of long term off road use. There are no good quality HID conversion lights available for my headlights.. I have sealed beams and have to convert them to H4 bulbs.

I will say that I do like the other lights they offer especially the Pro Dual Row series. They are the only supplier to state they have RFI filtering.

If anyone is interested in this brand of LED lights they are giving members of Pirate4x4 a discount. You do not have to be a paid member.

Posted: 7/29/2014 5:20:15 PM EDT

[#22]

My lights are wired straight to the battery, and the relay is wired to ignition aux power to actually trip the relay.

A few local guys suggested ordering copper insulation tape and covering the power supply with that. It seems cheap and easy enough, I'll give it a try.

Posted: 7/29/2014 9:29:47 PM EDT

[#23]

Quote History

Quoted:

I have decided to just use halogens for my headlights for now. The exposed fan on the back of the LED leaves me with doubts of long term off road use. There are no good quality HID conversion lights available for my headlights.. I have sealed beams and have to convert them to H4 bulbs.

I will say that I do like the other lights they offer especially the Pro Dual Row series. They are the only supplier to state they have RFI filtering.

If anyone is interested in this brand of LED lights they are giving members of Pirate4x4 a discount. You do not have to be a paid member.

View Quote View All Quotes

View All Quotes

Quote History

Quoted:

Quoted:
I hope auxiliary HID lights don't cause the same problem.

I went with KC Daylighter HID for my roof lights.

Haven't ordered the led light bar for the bumper yet. Going with something around 12" for use when winching.

Haven't decided what I am going with for roof rack side lights or back up lights.Still have to fabricate a roof rack mount and the rear bumper, tire carrier, fuel can holder.

Aftermarket HID's are notorious for RF noise actually.

If you're going with HID's, look into these.
LED Headlight

I run them on my Cherokee with a Anytone mobile (we all know how not so great the squelch circuits are on Chinese radios) and I've yet to have a problem with them. They don't bug the CB in the same vehicle as well.

I have decided to just use halogens for my headlights for now. The exposed fan on the back of the LED leaves me with doubts of long term off road use. There are no good quality HID conversion lights available for my headlights.. I have sealed beams and have to convert them to H4 bulbs.

I will say that I do like the other lights they offer especially the Pro Dual Row series. They are the only supplier to state they have RFI filtering.

If anyone is interested in this brand of LED lights they are giving members of Pirate4x4 a discount. You do not have to be a paid member.

Finally remembered the brand of the bar I have on my Jeep. Longshot Lighting 11" flood pattern. So far, the Head light LED's have held up to mud and water just fine (there has to be on hell of a departure down into some water to even dip the head lights). I've been expecting the power supplies to fall off (thy are just lightly screwed into the underside of the head light buckets right behind the bumper).

I never converted mine to H4…pulled the new lenses out of the box and put the LED's in. I honestly only know three light modes on a Cherokee…stock (either me or my parents have had an XJ since I was born), stock with the original housings from 1999, and H4 housings with LED bulbs. One thing I will say about those LED's…the way the power supplies are wired, when you switch to the high beams the low beam LED doesn't cut out like how the vehicle is wired.

I'll just leave these here…
Low

High

Rear

[ARCHIVED THREAD] - Off Road LED lights causing radio to cut out?

Outdoors » Ham Radios

Warning

Confirm Action

About AR15.COM

Stay Connected

Newsletter

Contact Us