Mobile Ham Radios and LED lights

[Citizen Rob]

I'm relativley new to amature radio so bear with me. I was playing around with my radio in my truck the other night, listening to a group of guys talking on a repeater located on Mt Diablo, I'm in Stockton 40 miles away. Everything was coming in pretty clear until I turned my headlights on. As soon as I did that the radio went quiet. I turned the lights off and the banter continued. I adjusted the squelch on the radio and was able to listen in with the lights on but there was significantly more static. Are my LED foglights and headlights affecting how well I am able to transmit and receive 2m and 70cm? Has anyone else experienced this and is there a solution?

 

[Prerunner1982]

Most definitely, some LEDs are known to cause RFI. Believe it has to do with the switching circuit that turns the LED on/off very quickly.
I was concerned that the LED headlights and LED strips I purchased for my Jeep would have RFI but so far so good.
You could try using ferrite cores/beads around the coax to choke off the RFI.

 

[TheRealMcCoy]

Most definitely, some LEDs are known to cause RFI. Believe it has to do with the switching circuit that turns the LED on/off very quickly.
I was concerned that the LED headlights and LED strips I purchased for my Jeep would have RFI but so far so good.
You could try using ferrite cores/beads around the coax to choke off the RFI.

WOW, thank you for sharing the knowledge. I have LED's and preparing to install my GMSR soon and this will help me troubleshoot the issue if I have it.

 

[Citizen Rob]

Most definitely, some LEDs are known to cause RFI. Believe it has to do with the switching circuit that turns the LED on/off very quickly.
I was concerned that the LED headlights and LED strips I purchased for my Jeep would have RFI but so far so good.
You could try using ferrite cores/beads around the coax to choke off the RFI.

Thanks for the suggestion! I was thinking that I might have to choke all of the different LED lights, but I'll try choking only the antenna and see how that works.

 

[Prerunner1982]

May not hurt to put some on the power wires as well.

 

[J.W.]

If your radio was plugged into your truck, it could also have been interference from your alternator charging when you turned your headlights on. Common problem.

 

[Sparksalot]

What kind of rig? HT or mobile? How was the power connected, to the battery directly or through a cigarette lighter?

 

[Citizen Rob]

What kind of rig? HT or mobile? How was the power connected, to the battery directly or through a cigarette lighter?

Yaesu FTM400 grounded to chassis, receiving switched power through a SwitchPro 5100. I'll try direct to the battery this weekend and check if there is a difference. I'll also check to see if the switched auxillary LED lights attached to the SwitchPro have any effect when they are powered on or off.

 

[Sparksalot]

Yaesu FTM400 grounded to chassis, receiving switched power through a SwitchPro 5100. I'll try direct to the battery this weekend and check if there is a difference. I'll also check to see if the switched auxillary LED lights attached to the SwitchPro have any effect when they are powered on or off.

I’m not familiar with the switch pro. There could be some hash leaking there. I’ve tried to always run my permanent rigs directly to the battery.

as a btw kinda thing, my current fun vehicle is an ex cop car. From the factory, all of the radio power wiring is completely separate from everything else all the way to the battery.

 

[Redbear]

I don’t know much about radios but I do remember that if wires are running along side each other the interference is magnified. Ideally, wires should cross at a 90* to avoid interference (not that it is always possible).

Are any of your wires from your radio zip tied to any other wire bundles? Maybe just moving the wires to a different location would help Instead of buying additional Insulation.

 

[The other Sean]

Also, where is your antenna mounted?

I have LED headlights as well and I get no noticeable issues with my Kenwood dual band radio though, my antenna is mounted to the right rear bedrail.

 

[Dolf]

The RFI might be coming into the radio via the antenna. Turn your radio on along with the lights so you can hear the noise, then unplug your antenna. If the noise goes away, the RFI is coming in through the antenna. If the noise stays the same, then it's being picked up through the power line, and you can put on the ferrite cores as referred to above.

 

[TheRealMcCoy]

The RFI might be coming into the radio via the antenna. Turn your radio on along with the lights so you can hear the noise, then unplug your antenna. If the noise goes away, the RFI is coming in through the antenna. If the noise stays the same, then it's being picked up through the power line, and you can put on the ferrite cores as referred to above.

Great tip

 

[Citizen Rob]

The RFI might be coming into the radio via the antenna. Turn your radio on along with the lights so you can hear the noise, then unplug your antenna. If the noise goes away, the RFI is coming in through the antenna. If the noise stays the same, then it's being picked up through the power line, and you can put on the ferrite cores as referred to above.

That is a great idea. I'll try that tonight. I've been messing around with antenna locations and found that there is more noise if the antenna is on a mag mount vs if the antenna is on a permanent mount on the bed of the truck.

 

[TheBronze]

Any of the wires attached to the radio my be acting as an antenna picking up RFI and bringing it in. Even the shielding of the coax can do this. Often this can be easily fixed by running all of the wires through separate torrid coils. These little snap on devices can bought cheap online and are easy to install. Placing one on the coax and power wires will hurt nothing and may very well solve your problem.