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Comment by andyidsinga | Hacker News Reader

speaking about interference : moved my home office to a new spot in the house the other day ago - which has 3 LED light bulbs for light in the space.

Turned on the ham radio - in scan mode - picked up someone talking, but noticed a bunch of static also being picked up. Didn't think much of it until I turned off the lights and the static went away. radio antenna was about 4 feet away from 2 diff bulbs (!).

These things are noisy ..thinking about trying a few diff brands to see if there is a difference.

also thinking about borrowing a buddy's spectrum analyzer to see if I can isolate the frequencies of the noise, might be able to put a a filter on the antenna.

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There are serious RF interference problems with some LED, CFL lights and dimmer products. Even low power (5W) lights can swamp the spectrum badly enough to jam out DAB and FM radio receivers.

[1] http://www.ledbenchmark.com/faq/LED-interference-issues.html

I wish the FCC would crack down. These devices are in violation of Part 15.

Also from some monitors and TVs. My Samsung monitor spews all across the 1.25 meter ham band. The form of the interference is a serious of regularly spaced narrow spikes across the whole band.

You might try adding snap-on ferrite beads to the power cord. If the monitor has an external switching power supply you could try replacing it; some of those are noisy. Otherwise, if it's an older monitor, the noise is probably coming from the CCFL power inverter (an internal AC power supply that powers the fluorescent backlight.) New monitors usually use LED backlighting.

Yes, I just installed new LED headlights in my car[0], and my FM radio gets staticy when I turn them on.

[0] https://www.amazon.com/gp/product/B07D3H1HWL

There is a lot of information available about this problem and how to solve it. Read this for starters [1]. The cause is the LED "driver" (power supply) and power cables; the PWM supply is making your LED power cables radiate RF energy.

[1] https://betterautomotivelighting.com/2014/12/31/how-to-remov...

I recall seeing a garage door manufacturer selling LED bulbs for $15 or $20 that don’t interfere with openers.

Personally, I’d just cover the bulb in a few layers of grounded chicken wire. But I’m cheap like that.

"Personally, I’d just cover the bulb in a few layers of grounded chicken wire. But I’m cheap like that."

Shielding the bulb won't help when the switching PS in the bulb is making the house wiring resonate. RFI problems frequently fail to yield to silver bullet solutions.

You may try to wind a few rounds of the AC wires to the LED bulb on a ferrite core. That may (or may not) reduce RF bleed through AC.

(shrug) RF is hard.

Yeah, my big plasma TV makes a heck of a lot of noise in the 70 cm band. I need to keep the rubberducky antenna far from it if I want to be able to receive anything.

Also, I've replaced the headlights on my car with LEDs. Much better visibility now, but the FM radio performs much worse. I'll have to figure something out, it's annoying.

For a room where you have radio equipment, I'd either install regular old incandescent bulbs, or DIY some LED strips driven by a constant-current linear voltage regulator (efficiency of the latter kinda negates the point of having LEDs though).

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