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Looking for knowledge on LED light interference of TV signals.

What specifically does it impact - UHF, VHF-high, VHF-low, FM?

What Is the impact level of different LED sources? For example, do LED streetlights cause more interference than household lights? How close does the LED light need to be to cause interference?

Do Ferrite Beads/Cores eliminate the LED interference?

Application of beads/core - clamp on incoming coax from antenna, before/after pre-amp, amp...?
 

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I can't say definitively without measurements but I would say the LED light will most likely produce less interference than fluorescent or other high efficiency lamps. That's because LED lamps rely on a solid state light source and typically consume less power. Other high efficiency lamps often used in streets rely on gas discharge or heavy metal ionization, processes that creates relatively high levels of RF interference. The most common household interference I've run into comes from conventional florescent lamps, small appliance AC motors and computers or other devices with high powered processors. (The computer interference is usually from poorly shielded high frequency circuits and cables, not the processors themselves.)
 

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Agree is tough to say without any measurements or definitive sources being pinned down.
eg - from identification and on/off testing.
ferrites can be useful for "supression" at the source. For example that is why you always saw a ferrite on the VGA interface cable of VGA monitors. But I don't think it will "eliminate".
If your looking to "eliminate" the best thing to do is identify and turn it off. A given...Not always practical. Beads are typically used on individual signal leads to a multi conductor control cable, before it leaves equipment or inside a connector shell. Some design has to go in to it however... At a minimum, in order to even choose a ferrite material to use you first have to at least know the frequency of the signal your trying to suppress, as there are different mixes of ferrite cores that are designed for specific frequency ranges. Choosing the wrong mix may not help at all.

Someplace around here I think I posted an example of some man made IX identification on VHF Lo caused by an LED TV set. Not being practical to merely turn off the TV set obviously...Ultimately I wound up moving the VHF antennas to the other end of the house, much further away from the source. As well as swapped out the Stellar Labs VHF HI antenna (PCB balun) for something else (uses a traditional 300/75 ohm xfmr) that didn't seem as susceptible to picking it up.
 

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On another note, with the advent of cheap SDR receivers that can be used as cheap spectrum analyzers, I have seen cheap EMI / EMC probes available on ebay and the like. They might be helpful in identifying sources of IX.
Google "Near-field Magnetic 9KHz-3GHz Field Probe EMC EMI"
 

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On another note, with the advent of cheap SDR receivers that can be used as cheap spectrum analyzers, I have seen cheap EMI / EMC probes available on ebay and the like. They might be helpful in identifying sources of IX.
Google "Near-field Magnetic 9KHz-3GHz Field Probe EMC EMI"
How to differentiate inherent noise in the receiver/other background noise from actual sources?

From what I’ve heard, LED noise is mostly due to poorly designed/made power supplies. What’s the remedy -ferrites or better power supplies?


Sent from my iPhone using Tapatalk
 

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All diodes produce some noise. However, it would be at a much lower level than CFLs.
 

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I use a portable AM radio. Just hold it up to an LED bulb. Amazing the amount of noise heard.
 

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From what I’ve heard, LED noise is mostly due to poorly designed/made power supplies. What’s the remedy -ferrites or better power supplies?
The right answer is better LED lamps. Switching power supplies all make some noise but it should be filtered out with good design. Small size and a race to the bottom on price points end up with some companies making inferior products. Maybe it would be worthwhile to get several makes of lamps and measure their noise output.
 

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Don't even get me started with LED Bulbs/Lamps... They are all junk in my opinion.
 
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