These self-appointed experts about interference matters, really say some incorrect things. Below are a few examples from a message board that I recently read Ham Radio Interference. That thread contains quite a bit of incorrect information...which I will debunk with fact.
"A few years ago the FCC started imposing new restrictions on hams including scanning their emissions for unintended directionality and the like. I believe every ham was required to scan the area for their particular modes of operation."
The FCC has never imposed broad restrictions on ham radio operators, beyond the rules and regulations published in Part 97. Unless there has been some level of enforcement action, operating restrictions are rarely imposed. The rules state, the FCC can impose quiet hours on hams (47 CFR 97.121). However, in my experience, I have never heard of anyone being restricted by the FCC for causing interference to their neighbor's TV set or Stereo. Long ago the FCC realized, 99.9% of interference to home entertainment equipment is usually caused by the poorly designed receiving equipment being sold in the U.S. from China and Southeast Asia. Even well known name brand products from companies based in Japan, many times do not have adequate shielding and filtering.
To maximize profits, manufacturers of home entertainment products take a chance to save a few dollars on each unit by not properly shielding and filtering that equipment. They count on the fact, that most of the equipment will never be co-located near an RF transmitter. Combining that equipment with the poor installation usually performed by most consumers, it's a recipe for interference. When consumers use cheap poorly shielded wires from the local big box stores or Wal-Mart, to interconnect that equipment, and then leave a rats nest of wire behind the TV or Stereo, they've also built themselves a great antenna to increase their vulnerability for interference.
Not withstanding that posters comments, the FCC does not randomly scan ham radio emissions for "unintended directionality". I don't even know what that term implies. The expectation from the FCC is we self-police our own. If a station is out of compliance, and is experiencing technical issues, that condition is usually immediately noticed by other hams. The offending station is usually informed there is an issue that requires their attention.
Another post in that thread reads...
"It is not legal for a ham operator to interfere with his neighbors' electronic devices. There are laws to protect the citizens from invasive radio frequencies."
There are no federal laws that "protect the citizen from invasive radio frequencies." There are no laws against something that does not exist. There is no such thing as an "invasive radio frequency." I believe the poster was trying to say "invasive radio frequency signals" a fact of life in our modern society. We are all subjected to it, and our bodies are invaded by it each day without our consent. Radio frequency energy is used by our cars, cell phones, broadcast radio and TV transmitters, radar systems for aircraft and weather, public service communications fire/police, home entertainment devices, even using an IPod/IPad or computer subjects us to small amounts of RF energy at various frequencies, it's everywhere.
There are some state and local nuisance laws in the U.S. that various localities try to enforce. However, those laws are only applicable to interference caused by non-licensed stations, such as CB radio operators using illegal non-type excepted equipment and high power external amplifiers. Since amateur radio is a licensed service regulated by the FCC, local and state law enforcement has no jurisdiction over the operation of a amateur radio station. The courts have repeatedly stated, the FCC has sole jurisdiction in the United States over all matters relating to any station licensed under the radio services regulated by the FCC.
In closing, one poster actually provided factual information....
"More than likely the fault is due to lack of/or inadequate filtering inside the TV or a break in the cable system. FCC Part 15 specifically states that the TV user must accept any unintentional interference from transmitters operating within specification. Check your user's manual."
That is a true statement. 47 CFR 15.5b, states that "Operation of an intentional, unintentional, or incidental radiator is subject to the conditions that no harmful interference is caused and that interference must be accepted that may be caused by the operation of an authorized radio station, by another intentional or unintentional radiator, by industrial, scientific and medical (ISM) equipment, or by an incidental radiator." In laymen terms, if you own and operate any device that is regulated under Part 15 of the Commission's rules (which most home electronic entertainment devices full under those rules), it must accept any interference that may be caused by the operation of an authorized radio station (i.e. a licensed amateur radio station; emphasis added), and may not cause interference to any licensed radio station.
When the marketplace became flooded in the 1980's with cheap electronics and home entertainment devices, the FCC revised Part 15 (54 FR 17714, Apr. 25, 1989, as amended at 75 FR 63031, Oct. 13, 2010), to state that Part 15 devices must accept interference from licensed stations FCC Part 15.
If you are a consumer, and are experiencing Radio Frequency Interference, do not jump to the conclusion that the source of the interference is from "that ham down the street." Interference that affects the operation of a device can come from many sources, sometimes even within your own home. Do not demand that he or she cease all operation. It is an unreasonable request, and can set a tone for non-cooperation. Unless the station is being operated not in accordance with good engineering and good amateur practice as determined by the FCC, amateur radio operators are under no obligation to help you solve the interference condition you are experiencing. Rather, if you suspect an amateur radio station is interfering with your equipment, politely tell him or her what you are experiencing and ask if they can help. Most amateur radio operators will be happy to help you track down the source of the interference, even if they are the source. Many times they can provide the technical assistance needed to help you correct the situation.