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FCC Really needs to enforce Part 15 Compliance…

pclover

pclover

Over the past two months some device near me outside my control has emissions so bad that a chunk of the FM band at 95 MHz is gone and replaced with a block of noise. I’m going to say likely a horrible solar inverter with no regards to actually designing something to suppress emissions. The strength of is intermittent at times tho. When it’s strong, A portion of the FM band is just gone.

And yes the AM band is also wiped out with noise and unusable.

I took a radio out in the street and it’s still very present.

I’ve complained before, But does the FCC actually review part 15 certifications with random checks?
 
Several years ago the Commission shut down several of its local field offices which used to deal with nuisance complaints like yours. Unless the matter is flagrant, and affects a lot of people, it's pretty unlikely that a regional field office would mobilize a team for a visit.
 
Kelly A said:
Several years ago the Commission shut down several of its local field offices which used to deal with nuisance complaints like yours. Unless the matter is flagrant, and affects a lot of people, it's pretty unlikely that a regional field office would mobilize a team for a visit.
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Yeah, I've never filed a compliant for a Part 15 violation. Just meant that I've complained about it on here.

But it seems like if you did file a complaint nothing likely will happen.

I figure resources are only actually used for cellular, aviation, or public safety interference.
 
pclover said:
Yeah, I've never filed a compliant for a Part 15 violation. Just meant that I've complained about it on here.

But it seems like if you did file a complaint nothing likely will happen.

I figure resources are only actually used for cellular, aviation, or public safety interference.
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Why don’t you actually file a complaint and find out?
 
I suggest reading Part 15.

Read it as a disinterested third party without an agenda, bias or leading conclusion. Try interpreting it as a regulatory agency or attorney representing a client would. Consider that Part 15 is a Federal regulation and there are political implications, just as in other acts of government.

Consider the users of radio-frequency devices that would be impacted by a change in the status quo.

Consider impact on consumers and quality of life if things are changed in order to have a more pristine radio frequency environment.
Such as- how many billions would it cost to reduce incidental electromagnetic wave radiation by electric power lines?
Who would ultimately pay for this, and is everyone OK with the physical changes in their neighborhood?

Think of this as an environmental quality matter, and view it through the eyes of the general public and human nature.

Then read Part 15 again.

Federal Register :: Request Access

www.ecfr.gov www.ecfr.gov
 
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pclover said:
But does the FCC actually review part 15 certifications with random checks?
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The short answer is no. They barely have enough staff to deal with pirates in major markets. If you're a licensee, your complaint will carry more weight than if you're not. If you have the equipment, identify the source of the interference. If you do most of the work, they might handle the enforcement. You could also get in touch with an affected licensee and propose to file a joint complaint.
 
WIFI will mess up all but the strongest FM signals with white noise all over the dial and something that sounds like a bunch of tones on certain frequencies.
 
Flying Dutchman- do you mean WIFI will soon be overloading FM receivers or broadcasting on the same frequencies as FM stations?

I think anyone who files a complaint about interference from device they own and operate inside their home, will appear foolish. That person filing the complaint would be objecting to their own action. Like calling the police about too much noise, when you are the one making the noise.

I have WIFI transmitter, and keep it on the other side of the house. I don't make a point of listening to AM radio next to it, or right next to some ethernet cables running to my computers. I keep my cell phone on the other side of the room. No need to be near that transmitter all day. I am a bit annoyed at electrical noise that may be coming from a UV bug light array the neighbor operates next door, but whatever.

This subject connects to many fundamental issues. Like to what extent can people in adjacent apartments in a building complain about actions of their neighbors.

We are not all living on 640 acres granted to our family from one of the Homestead Acts.
 
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Greg Strickland said:
Flying Dutchman- do you mean WIFI will soon be overloading FM receivers or broadcasting on the same frequencies as FM stations?
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I think it's some subharmonic of 2.4 GHz. causing the issue. Take a portable FM radio near your router and you'll hear it. I can even hear it out in the yard. Some routers put out half a watt. The FCC allows up to 4 watts on 2.4 GHz. There's a lot of stray RF now days.
 
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Flying Dutchman said:
I think it's some subharmonic of 2.4 GHz. causing the issue. Take a portable FM radio near your router and you'll hear it. I can even hear it out in the yard. Some routers put out half a watt. The FCC allows up to 4 watts on 2.4 GHz. There's a lot of stray RF now days.
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Which FCC rule allows 4 watts? 15.249 specifies a field strength of 50 mV/m at 3 meters in the 2450 and 5800 MHz bands. This calculates to roughly 0.5 milliwatts into a dipole antenna. I believe this section applies to consumer modems/routers.
 
I think a more likely cause of interference to FM broadcast receivers is digital data on associated ethernet. A reasonably well-designed 2GHz transmitter that is part of a WIFI device should not be radiating signal in the FM broadcast band.

Should be no surprise a 100 MB/s ethernet connection would radiate an electromagnetic wave. Or a computer.
Make a 100 MHz square or sine wave and connect it to a piece of wire about five feet long.

I don't think an electrical digital word (binary data) is a sine wave. It contains harmonics, which is the essence of a square wave.
At power (such as in an electric vehicle) it is possible that binary data is more efficient that sine wave.
At high power creation of on-off binary is more efficient than creation of sine wave (unless more steps are taken).

Cleaning up electric vehicles requires re-engineering the system to operate at data rates unlikely to cause interference to users of electromagnetic waves, and right now the spectrum is packed. Or it requires making "softer" data and adding more shielding.
 
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Flying Dutchman- Thank you for posting the link.

Kelly A- to your point about light bulbs-

One of the "issues" of Part 15 is individual device emission compared to cumulative emissions from a number of devices in a small area. One bulb producing 25 microvolts at 3 meters on the AM band is not a problem, but a house full of them could be.
Part 15 may not have anticipated a car stuck in a traffic jam on the freeway with a half dozen Part 15 devices within 125 feet.

Same could be said for linear sources of Part 15 emission, such as a electric power line.

Kelly A- As I'm sure you know, some Part 15 operators have set up multiple transmitters simulcasting their programming to to circumvent the limited coverage area of a single compliant Part 15 device.

I think those who are this enthusiastic about broadcasting should come over and join us on the licensed side.


pclover- now, finally actually responding to your question-

Perhaps try walking around with the radio to determine overall strength of the interfering signal, and where it might be coming from. If the radio has a telescoping antenna you could fully retract it to make location of the signal source easier.

Can you look around and see likely sources of the signal, such as rooftop solar? Once the source is located you can determine how to proceed.

I assume you have heard this on more than one radio? You are not really close to a licensed broadcast station, correct?
 
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Greg Strickland said:
Flying Dutchman- Thank you for posting the link.

Kelly A- to your point about light bulbs-

One of the "issues" of Part 15 is individual device emission compared to cumulative emissions from a number of devices in a small area. One bulb producing 25 microvolts at 3 meters on the AM band is not a problem, but a house full of them could be.
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Not if your radio is sitting less than a foot from a lamp with an LED bulb.
Greg Strickland said:
I think those who are this enthusiastic about broadcasting should come over and join us on the licensed side.
Click to expand...
Sure, like others they could game the system and set up LPFM's. Join the club.
 
Greg Strickland said:
Consider impact on consumers and quality of life if things are changed in order to have a more pristine radio frequency environment.
Such as- how many billions would it cost to reduce incidental electromagnetic wave radiation by electric power lines?
Who would ultimately pay for this, and is everyone OK with the physical changes in their neighborhood?

Think of this as an environmental quality matter, and view it through the eyes of the general public and human nature.

Then read Part 15 again.

Federal Register :: Request Access

www.ecfr.gov www.ecfr.gov
Click to expand...
Allowing people to do whatever they want will mean part 15 has no meaning. Having a device emit massive spurious emissions because it's clean is unacceptable and sloppy engineering. Part 15 sets limits for a reason.

A lot of RFI could reduced or even eliminated from devices if they would spend a few dollars on parts. Such as some extra filter caps, inductors, ferrite chokes etc. Of course they don't because it's penny pinched. Seems the most common offender is terrible low quality SMPS.

I guess until the FCC steps in actually cares it will continue to get worse. It seems they will if Aviation, Public safety, or Cellular is affected. There has been a few cases of Part 15 devices causing interference here.
 
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A few months later I found the the main source of my issues. Tho outside noise still exists.

The cause? An Air Ionizer...

Claims to be Part 15 yet it wipes out 95 MHz when an antenna 50 feet away. Sure...
 
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