Discussions

[silvalves]

I live in an apartment building with a balcony facing SW (237º) in a New York City suburban area. To receive OTA TV in my TCL Roku TV, I have tried two different flat antennas, with and without an amplifier. Have also tried a small antenna made by Channel Master. All of these antennas receive dozens of channels and sub-channels. Today I was able to identify that pixelation occurs when there is interference with FM radio stations. This occurs at any time of the day, but most of the time from around 6:30 and 9:30 PM, but I have also identified interference at other times. The channels affected are 7, 9, 11, 13, 14, 33, 46, and 55 (and their sub-channels). I have moved the antennas to various locations in my 3rd-floor balcony and the result is always the same, the pixelation occurring when there is interference with FM stations, albeit it is weaker near the antenna as compared with inside the room with the TV set.
There are exceptions to this rule, but they have no distinguishable pattern, for one day I get a perfect signal all the time, while most of the other days the problem exists. Can anyone help me identify what is the cause of this unusual situation? Are there filters that could counter the interference? All the help of the community will be more than welcome.

[makaiguy]

@silvalves-

How have you determined that your problem is caused by FM interference? 

Standard commercial FM radio broadcast frequencies are tucked between the frequencies used for tv channels 6 and 7.  (Before tv went digital I used to listen to the audio for my local tv6 on my FM radio.). So it wouldn't seem that commercial FM would interfere with that wide a range if channels.   Some so-called digital tv antennas (there's no such thing actually, they work for analog as well as digital) have FM filters built into their electronics to trap FM broadcast frequencies, making them unsuitable for use as FM radio antennas.

At one place I lived I had occasional tv interference problems that were eventually traced to a neighbor with a CB radio broadcasting at way over the CB power limits.

[silvalves]

Hi, makaiguy,

Thank you so much for your insights. I believe there was a misunderstanding or I did not explain correctly my problem. I mentioned FM radio stations because, at my place in NY City’s suburbia, I have good reception of FM. Three days ago I noticed, that all of the FM stations were taken by interference from some source that so far I haven’t been able to pinpoint. I decided to check the TCL Roku TV that I have had for some 18 months and the interference was present over various channels, the strongest being channels 7, 9, 11 and 13. I kept monitoring the situation, hearing to the FM through earphones and watching the TV channels. The moment the interference stopped over the FM was the exact moment when the TV stations returned to normal. Later in the day, the same situation occurred and it has been re-occurring in the same pattern, mostly in the early morning (6:30/8:00) and early evening (6:30/8:30 or a little later).

I’m considering taking the matter to the FCC, for the interference must be in breach of some of its regulations. 

Do you have any suggestions for me regarding this unusual problem?

Once again, thank you for your interest in my problem and for your kind answer

[makaiguy]

@silvalves-

There's probably some specialized spectrum analysis equipment that could be used, but that's way beyond my pay grade.  I suspect for most of us a complaint to the FCC may be the only recourse, but I have no idea how responsive they will be if yours is the only complaint.  

The past interference problem I mentioned WAS finally traced to the over-powered CB as a result of several complaints to the FCC.