Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

FM Radio Station on House Electric?

  1. Feb 3, 2005 #1

    Moonbear

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Okay, I guess this falls into the electrical engineering category.

    Ever since I moved into my house, I've noticed this odd problem of picking up a particular FM radio station on my phone receivers as well as it bleeding through across ALL the FM stations. I only have this problem in my house, not in my car, not on cell phones, not anywhere else in town. I never really knew what caused it and it's really only a minor nuisance.

    Well, not long ago, I had a set of speakers plugged in and turned on with no receiver connected (it's an old set that I used to use on a computer, but had just been plugging a small CD player into and had disconnected the CD player). They started playing that same radio station! Is it possible I'm somehow picking up this radio station through my household electrical wiring? Or is there some other way this interference can be occurring? I realized I don't pick up this interference on a battery-operated radio, only if it's plugged in.

    And, then the big question...if I AM picking this up on my electrical wiring, does that mean something is wrong with the wiring that I need to get an electrician in to fix something, or does that mean there's something wrong with how the radio station is transmitting their signal and I should be calling and complaining to them or the FCC or something? Or is this just some weird quirk from living in too close of proximity to the radio tower (I'm not sure where they are exactly, but I think they transmit from someplace near my house).
     
  2. jcsd
  3. Feb 4, 2005 #2

    NoTime

    User Avatar
    Science Advisor
    Homework Helper

    Sounds like you live fairly close to the transmitter tower.

    Nothing particular to worry about on the house wiring.
    This is not an indication that there is something wrong with the wiring.

    What you can do about the issues you are having is more complex.

    The house wiring can act as an antenna.
    One thing you might try is installing a balun on the power cord of devices having problems, as close to the device as possible.
    Radio Shack does or did carry these.
    It is a ferrite core. Wrap the power cord into the slot as many times as will fit and snap it shut.
    Might help with the phones as well on the phone cord.

    If this doesn't help there are other things you can do as well.
    Like installing shielding or specialty traps.

    Good luck.
     
  4. Feb 4, 2005 #3

    Moonbear

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Thanks. I was starting to think I was nuts about this and nobody was going to answer. I'm glad to know it's not a problem with the wiring. What is a balun, and how does it work? I've never heard of that before (how is it pronounced? Is the 'u' short or long? If I go into a Radio Shack and ask for one of these, I don't want to sound like a complete idiot.) I'm not too worried about the phone lines, because it usually isn't loud enough to hear on those, and when I do, I just tell people it's the wire taps the FBI has on my phones :rofl: But, it certainly is a pain on anything that has speakers (like the radio), so that's where I'd really like to eliminate the problem. I have an old radio I can play with if this does anything to the wire itself.

    No possibility of tuning the house wiring to the station I want to listen to more often, huh? :biggrin: :rofl:

    Anyway, it's good to know that even though it can be a nuisance, it isn't indicating anything wrong. I have enough things to fix in this house, and wiring is the one I don't consider a do-it-yourself project (other than minor things like replacing light fixtures, switches or outlets).
     
  5. Feb 4, 2005 #4

    NoTime

    User Avatar
    Science Advisor
    Homework Helper

    Well, you could buy a house next to a station you liked :rofl:
    Or make a lot of requests :surprised

    The 'u' is like in undo.
    Not exactly sure what they call it at radio shack.
    Perhaps "power cord RFI filter".
    RFI=radio frequency interference.

    Functionally you would be adding an inductor.
    It does not cut or otherwise damage the cord, so you can remove it later.
    No need to practice :wink:

    Cheap radios are most likely to be a problem.
    The circuitry is not good enough to reject a strong signal, even if the power cord is fully isolated.
    Not usually a problem for car radios.
    These tend to be designed very well.

    For stereos with separate speakers a couple .001 mf caps across the speaker terminals can work wonders.

    I used to do a lot of this stuff for my ham friends.
    The neighbors tend to get annoyed when they hear you on the TV or stereo.
     
  6. Feb 4, 2005 #5

    Moonbear

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    *smacks forehead* Why didn't I think of that before? :rofl:

    Okay, good. Well, I can always browse around Radio Shack...oh, wait, that only ends up costing more money...I'll just look for the oldest guy working there and play my dumb blonde routine "Well, I need this thingy, but I'm not sure what it's called..." Only the old-timers can figure out what you need from that sort of description.

    :frown: All I have are cheap radios. Haven't invested in a stereo system yet. There didn't seem much use when I can get one station loud and clear through anything plugged in. :biggrin: I figure I should probably get myself a proper table before I worry about stereos (I still eat at a card table).

    Um, yeah. I used to pick up CB radio transmissions on my TV when I lived in an apt near a busy road. Though, to tell the truth, it was more interesting than anything on TV.

    Thanks again!
     
  7. Feb 4, 2005 #6

    NoTime

    User Avatar
    Science Advisor
    Homework Helper

    Ain't that the truth.
    500 channels... and nothing on :biggrin:

    You could always use that card table to play cards :smile:
     
  8. Feb 4, 2005 #7
    Radio interference is always an FCC issue

    The station in question may be operating in violation of its licence. My experience in radio tells me that if you call the FCC, they will be very interested to hear about this and will take care of it right away. Here is a toll-free FCC phone number that might work:
    888-CALL-FCC (225-5322)

    By the way, what are the call letters? Is it a pirate station? If it is a pirate station, it may literally be transmitting from next door to you. A related possibility is that someone living near you hooked up a small transmitter (lots of these little FM transmitters are on the market these days) to his computer so he could hear his MP3 collection throughout his own house, and that he didn't realize he might be bleeding out into the neighborhood.

    If the latter is the case, the FCC will triangulate him (pretty easy to do) and go knock on his door. As an alternative, you can triangulate him yourself right now with a portable radio and go knock on his door.
     
  9. Feb 5, 2005 #8

    Moonbear

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    No, it's not a pirate station, it's a pretty popular oldies station in the city (well, as popular as an oldies station can be :biggrin:).

    Thanks for the number to call. That's what I wasn't sure about, whether this is an FCC issue or just my problem to deal with (and I really didn't want to call the FCC if it was something wired wrong in my house causing the problem, which it now seems is not the issue).
     
  10. Jul 30, 2008 #9
    OK, I understand the phones picking up radio. How about HVAC ductwork or household conduit? Several of my neighbors in our new subdivision in Lockport Il are picking up WJLL am1160 on thier phones AND THROUGH THE WALLS! Sorry for yelling but I cant believe it. Again, I can see the phones picking it up, but they hear this at night with all phones off and baby monitors off and such. We live only about 3000 feet away from the 6 antenna aray that pumps out the night time broadcast. Can anyone explain the ductwork and fireplace picking up the transmission? Here is a good site to check for transmitter locations. Our subdivision is just to the NE of the antennas. http://www.radio-locator.com/cgi-bin/finder?sr=Y&call=WYLL


    Thanks!!

    Mark
     
  11. Jul 30, 2008 #10

    NoTime

    User Avatar
    Science Advisor
    Homework Helper

    Welcome to PF.
    <lol> I've been posting here a while.

    Just about any chunk of metal can rectify an AM radio transmission, given the proper conditions, even dental tooth filings.
    In this case improper, but...

    For ductwork, a lot of it is just put together as slip fittings and sticky tape wrapped around the joint to seal it.
    Build up a little oxidation in the joints and you have a rectifier.
    You could try pushing or pulling on the offending segments to see if it stops.
    A few sheetmetal screws in the joints might help.
    Edit: if there are screws try tightening them a 1/4 turn or so.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: FM Radio Station on House Electric?
  1. Fm radio receiver (Replies: 9)

Loading...