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svcattle
08-16-2016, 00:13
I have a question for somebody that knows about electrical interference. I finally got my bumper lights wired up made a nice little harness for them and ran power off the battery and grounded directly to the battery as well anyway when I flip the lights on I get static through my radio . I think the problem is from running the 12 volts into the cab . My question is how can I fix the problem ? Not much good bieng able to see but not have a radio.

Dvldog8793
08-16-2016, 03:30
What type of lights are they?

svcattle
08-16-2016, 18:40
What type of lights are they?

Led type

Dvldog8793
08-16-2016, 19:14
The power regulator in some LED type lights will generate spurious RF that can be picked up by radios. Sounds like you lucked out and got some LEDs that do just that.
If they are individual lights you can see if it is a defective unit by trying them one at a time.
If it is a large "bar" type then you could try taking it back to where you bought it or call the company.
The bad part about this type of interference is that it is not something that is coming through the power system, it is being broad cast. So the only real way to deal with it is to somehow shield the offending party from everything else.
I have an ISS PRO pyrometer that had a similar issue, I solved it by wrapping the offending power supply in foil. Not really an option with your lights.
Hope this helps!

svcattle
08-16-2016, 22:35
No but maybe I can wrap the power coming in and the antenna wire with some of that foil backed ducting tape?

Dvldog8793
08-17-2016, 03:58
You can....but the interference isn't coming from the power wires. It is being transmitted through the air to you radio. Could be coming in through the antenna or directly into the radio. If your power wire is in DIRECT contact with the antenna wire then separating them might have some effect.
This is some of the most difficult to eliminate RF interference. In my experience we would just replace the offending component(lights or whatever).

DieselDavy
08-17-2016, 08:08
This is an problem in all of the LED lighting world, not just the automotive segment. The FCC is starting to finally pay attention to folks in the RF world. (HAMs and RF design engineers in particular) Dvldog is on the right track. You'll probably need to buy a higher quality LED product. Wrapping the switching Power Supply (the offending section of the design) could work, but as a jury rigged fix, it will be subject to all the vib and temp extremes of the automotive world, it will always be waiting to bit you further down the road. If consumers shun these offending units, the manufacturers will learn they need to do things right the first time. These type of offenders don't only effect your radio, they add to the noise floor, slowly causing more and more problems with other systems as the number of units get added to our environment.
With all of the above being said, I understand my fellow diesel junkies, you'll probably just fix it and move on....(I probably would also) But we really should hold the product manufacturers responsible by not supporting inferior products!
Dave

svcattle
08-17-2016, 13:20
Thanks for the replies guys I guess that's what I get for buying the 20$ for two lights on eBay . I will put these on the tractor and find some higher quality Lights for the truck .

svcattle
08-28-2016, 21:36
An update now I only have interference when the engine is running I can turn the lights on without the engine running and no interference

Dvldog8793
08-29-2016, 05:57
different lights?
If the noise is RPM related then I would suspect the alternator. Check all the grounds and related connections. Make sure the case of the alt is grounded good.
Does the truck have an aftermarket radio/Speakers?

DieselDavy
08-29-2016, 08:44
Wow! I don't know what the problem could be then. I still stand by my earlier post concerning LED lighting, but your lights may not be the issue in this case, unless it is susceptible to the noisier voltages that the alternator creates while charging the battery. Seems unlikely, but you never know...
A way to check this might be to put a charger on the battery with the truck not running and see if the noise is still generated when the lights are on?
Let's see if DMAXMaverick can jump in here and give his opinion.
Dave

DmaxMaverick
08-29-2016, 11:53
(since I was called)

I dunno. Seems like plenty of help already. If it were me, I'd start with a ferrite buffer tube around the LED power and ground wires (paired, looped through twice). Many computer power, serial data and video cables have these, and they work (and are free, from old computer junk). That will eliminate the LED's as the source. If it persists, I'd suspect a poor ground, probably the instrument cluster or dash support. It could also be an indication of an alternator about to head out. Additional loads, especially inverted circuits, can reveal or exaggerate existing issues.

Dvldog8793
08-29-2016, 14:20
Howdy
Did you replace the lights and then noise changed or did the noise change all on it's own?
Factory or aftermarket radio?
Is the noise present with the radio turned off? You might have to put your ear right up to the speaker to test this.
Does the "new" noise change pitch with RPM?
One way to eliminate the Alternator as a possible is by removing the belt and see if the noise goes away.

svcattle
08-29-2016, 20:37
I coated the lights with some cheap silicone on the back of each light I'll have to look for the noise button it is a factory radio