Getting a complaint about my radio causing interference with DTV Reception

Discussion in 'Discussions, Opinions & Editorials' started by N0MIO, May 20, 2011.

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  1. N0MIO

    N0MIO Ham Member QRZ Page

    Hello all, this is KD0JWY Richard from Ozark, Missouri. I am getting all kinds of complaints from one apartment which happens to be across the hall. I am running a Yaesu FT-60R and even with my Yaesu FT-60R they still complain. I am getting verbal complaints and also physical complaints. I need to know what to do. I have a copper j-pole and only run 50 watts to use simplex. Otherwise it is only 5 watts. It does interference with our television in the house and since we use DTV over the air I know what they are talking about. But my wife doesn't mind it most of the time. I know it's not my equipment but they just moved in and will be here for at least 10 more months and I don't want to have to get the cops all involved to fix this. Any help would be appreciated. Thanks again.
  2. KA9VQF

    KA9VQF Ham Member QRZ Page

    I’d probably use a claymore.
  3. N0CRS

    N0CRS Ham Member QRZ Page

    Could you reason with these people and work out a time they watch tv , and stay off for that time period ? Also ,if you
    can get by using low power , by all means , do so . When you rent , you have no rights .
    One other idea , move your ham radio activity to a remote location . Or find a local ham , or someone who has
    property that wouldn't mind antennas . Other than that , there is always mobile operating .
  4. K0SPN

    K0SPN Ham Member QRZ Page

    If someone is physically threatening injury/damage to you, your wife, or your property, you need to document it as completely as possible (e.g. dates, times, actual language used) just in case anything does actually happen; if you really feel threatened at some particular instance, you should definitely call the police.

    I'm no expert, but everything I've seen says that as you are a licensed operator, and you are interfering with a (presumably) Part 15 device, they can't stop you from using your equipment; as long as it's within it's legal specs. I'm sure someone will correct me if/where I'm wrong.

    In the May 2011 CQ Magazine, there is a nice article called 'Fighting TVI in the Digital World' (pp. 77-80) and gives a schematic for a simple high pass filter. If you aren't a subscriber, I'd recommend you pick it up at your local magazine outlet as there is some good info in the article (and some stuff I didn't realise).
    There are a number of places online where you can find calculators that will give you the same schematic and let you input your own parameters to customize the filter, though the CQ schematic uses standard value caps, so unless you want to try and create the right values with multiple caps, just stick with the published version.

    I also use OTA TV, and while I haven't had any issues (yet), I don't really watch TV and operate at the same time, but I do plan to make one very soon and see if it helps my reception (I have some minor issues, just an annoyance really) and as a preventative because of some info given in the article.
    If you'd like, I can give you my parts list for my order.

    Online calculator that I used in my research (set: high pass; 5 pole' 170MHz; 75 ohm; use the Chebyshev values in the second circuit [DC open to ground])
  5. K0SPN

    K0SPN Ham Member QRZ Page

    This is not true.
    You have a lease, just like everyone else there, and you need to read it and be sure of what it says.

    My lease says that I cannot "install" any antennas (without approval), yet I have a HF vertical, 2m/70cm vertical, and a 6m dipole, yet have not made any modifications to the building.
    The HF vertical is attached to a pipe in a 5 gallon bucket sitting on my deck, the 2m/70cm antenna is C-clamped to a railing, and the 6m dipole uses some hooks that a previous tenant used (presumably to hang plants). The cables go through a 3/4" plywood board that fits in my window. I'm sure I suffer some thermal inefficiency with my setup, but nothing is "installed", i.e. permanently modifies the building; when I leave, no one can tell that I did anything.

    You may be in a different situation, but that's why you need to read your lease and know exactly what it says.
  6. N0AZZ

    N0AZZ Ham Member QRZ Page

    I run legal limit on HF and 300w on VHF I have DTV off the air plus Direct TV 4 LED/LCD TVs + 6 computer monitors all of them in same room as shack except for one laptop.

    In one instance that do have any problems and it is with a new 60" Sony wall mounted in the living room and that is on 20m only. What it does is bring up the menu screen on the TV when I transmit that's it and at legal limit only then.

    I do have yagi's for all bands 40-440m and a vertical for 10-80m and also a wire for 80/160m.

    I think it is in your neighbor's system if so and you are legal he must accept it legally but it's better if you can work with them.

    Good Luck and lots of good DX.
  7. NN4RH

    NN4RH Subscriber QRZ Page

    If I read correctly, the interference also occurs in your own apartment. So the problem is not just with the neighbor's TV. You'd be a lot better off if you could demonstrate that no interference occurs to your own TV. Then you could safely blame it on the other guy's TV instead of your ham gear.

    A couple of things not clear from the post, though.

    Does the interference occur with 5 watts or only the 50 watts transmit?

    By "DTV over the air" do you mean that the TV reception is over the air? Not cable or satellite?

    Where is the J-Pole relative to the TV antenna or TV feedline for the antenna?

    Is the J-pole inside the house or attic, is it near any electrical wiring?

    How well is it matched to your feedline? Any chance of high SWR or high common-mode currents on the feedline?

    Is your grounding appropriate? i.e. you are not trying to use the electrical power ground in the building for RF grounding.

    Once you're sure that your ham setup is clean, and if you still get interference on your own TV, you can experiment a little to see what it takes to get rid of it, before suggesting to the neighbor a fix. For example, ferrites on the power cords or TV feedline (assuming it's coax not twinlead).

    The neighbor most likely won't accept any solution you offer, and if you even touch his TV he'll probably will blame you for anything that ever goes wrong with his system for the rest of your life, but suggesting a solution may be taken as a sign of good faith at least.
  8. WA9SVD

    WA9SVD Ham Member QRZ Page

    First of all, you have to make sure YOUR station is "clean." You may (probably) have radiation from the outer conductor of your feedline to the J-pole, and THAT is the first issue. In your situation you may need a "balun," which can be a coil of about 10 turns of coac would around a 2 liter soda bottle (as a start; ) a more effective solution would be about a dozen appropriate ferrite beads as close to the feedpoint as possible. (Palomar and other suppliers can recommend the proper beads for your coax size and frequency.)
    If you can eliminate the interfewrence to YOUR home installation, and demonstrate that to your neghbor, then the problem is within the neighbor's installation of the DirectTV; it could be a bad shield cable connection along the way, or an unauthorized tap in the system, either at your neighbor's or somewhere "up stream." Either way, if your installation is "clean," it's time for the DirectTV folks to work on a solution.
  9. N0MIO

    N0MIO Ham Member QRZ Page

    yes it does It even if I run 5 Watts. the antenna is up in the attic and has an swr of 1.2. my yaesu ft60r also does it. only at 2.5 and 5 Watts. furthermore I even tried the elk antenna which is what I use for portable satellite work and its the same issue. the j pole has great shielding on it. I may try some other things. the neigjboor does use a cheap radii shack amplified antenna which personally is what I think the problems is. would a low pass or high pass filter fix it.
  10. KB1NXE

    KB1NXE Platinum Subscriber Platinum Subscriber QRZ Page

    If you are being physically threatened, do not hesitate to call the cops. For each incident you allow to go unrecognized, the next one will be an escalation of the previous one. The first one may be a push, the second you'll get knocked on your butt, the third a punch, etc. Or it may be vandalism to your property. It will follow a similar pattern. Remember, as a licensed Ham, you are not doing anything illegal! DO NOT LET IT GO!

    Technically there has been some sound advise here. Heed that. Heed this also!
  11. KG4RUL

    KG4RUL Ham Member QRZ Page

    From the Technician Class Licensing Question Pool:

    T7B06 (A)
    What should you do first if someone tells you that your transmissions are interfering with their radio or TV reception?
    A. Make sure that your station is operating properly and that it does not cause interference to your own television

    T7B07 (D)
    Which of the following may be useful in correcting a radio frequency interference problem?
    A. Snap-on ferrite chokes
    B. Low-pass and high-pass filters
    C. Band-reject and band-pass filters
    D. All of these choices are correct
  12. K0SPN

    K0SPN Ham Member QRZ Page

    Something I meant to add in my first post about the filter was that you can try making one to test with your TV to see if it solves the problem, and if it does, give it to your the neighbor (making another for yourself). You should also mention that while you are federally licensed and not legally obligated to fix issues with his equipment, you are doing so as a good will gesture (making sure to document this).

    As I said, the parts are easy and cheap to obtain and you almost certainly won't damage anything by trying.
    The CQ article says building the filter in a shielded box is better, but it works pretty well using just 'dead bug' construction.
    I've got some spare double sided copper clad (PC) board that I'll be using to fabricate a box for mine, but any smallish metal box you have or buy should work just fine.
    The article also shows a Radio Shack FM Trap (~$8) which some TV stations who broadcast in the channel 8-13 range are giving away. You may be able to open this box up and have most of the parts already installed and in a nice package.

    And of course, there is plenty of other good advice already given.
  13. K0RGR

    K0RGR Premium Subscriber QRZ Page

    We need a lot more information here. There is no way that a healthy TV set, DTV or otherwise, should be affected by a 5 watt handheld, particularly if the antenna is outside!

    What channels are affected on the TV, and what does the interference look/sound like? Let's start with your TV - what channels, and what kind of antenna are you using, and how close is it to your transmitting antenna?

    My 2 meter antenna sits directly above my TV antenna, and no problems with DTV here at any power level up to 100 watts.
  14. WB2WIK

    WB2WIK Premium Subscriber QRZ Page

    No problem with DirecTV here with 1 kW output on two meters, using antennas that the dish is looking right into.

    Interfering with the LNB is almost impossible unless you're working the 1.3 cm band.

    I suspect something is very amiss. RFI/TVI might happen if someone's using the "RF input" of their TV set (tuned to CH-2 or CH-3) from the converter, instead of using direct connections that bypass the tuner, which is normally done, and then the TVI would be to the set itself and not really DirecTV. Although I've really never seen that, either, but it seems possible.
  15. KE7AUB

    KE7AUB Premium Subscriber QRZ Page

    Digital TV over the air with amplified TV antenna is bad news. I had same issue with Analog TV and an amplified antenna. VHF/UHF ham antenna was 25 feet away, and with the amplified antenna 'on' even at 5 watts I could notice the VHF signal from the radio. Once I turned 'off' the amplified TV antenna, the problem went away. Try to have the party in question turn off the amplified antenna and see what happens. It's also possible that the wall wart cord for the amplified antenna is helping pick up your radio signal and feeding it in to their TV. Sort of how it works with external PC speakers and their wire connections.

    Also, do you have an amplified antenna for OTA Digital TV reception (cheap or expensive)? You shoud not be interferring with your own TV. XYL should not have to suffer (well, it is probably not too bad of interference, based on my experince, but still....) Check the connections and make sure they are tight. Same applies to whatever else you have connected to your TV (like a DVD player or VCR).

    Also make sure all your conntections between the radio and antenna are good. If you have an HT try transmitting with that and see if you get the same issues. Get close to your own TV and see what happens.
  16. WB2WIK

    WB2WIK Premium Subscriber QRZ Page

    Oops, sorry, my comments weren't really relevant. I just re-read and see by "DTV" you only meant over-the-air digital TV, and not via satellite.

    Sure, it's possible to interfere with that, especially if anyone's using preamps or your transmitting antenna is in very close proximity to their (or your) receiving antenna.

    It's best to use the best receiving antenna possible, aimed properly, and avoid preamps.
  17. KF6ABU

    KF6ABU Ham Member QRZ Page

    id try a 1/4 wave vertical instead of the j pole.
  18. KB9BVN

    KB9BVN Ham Member QRZ Page

    Junk TV sets are a problem. If your 5w HT on 2m or 70cm is screwing with their TV set then they need to junk it and buy a different one. If they have made threats to kick your butt, then call the cops and make them document it, then file a complaint with the owners of the rental. Tell them you filed a police report and if the idiot carries out his threat, you will be forced to sue.
  19. AG3Y

    AG3Y Ham Member QRZ Page

    In an earlier neighborhood where I lived, my transmissions would cause all kinds of TVI in an apartment about a quarter block away from me. I was using all Collins equipment at the time, with high quality RG-8 coax feeding a three band cubical quad. I was very sure that my setup was not causing the problem since our TV set was clean as could be.

    The cable company was called in to investigate the situation at the apartment building, and their findings were that the building was festooned with all kinds of illegal cable feeds to non-paying users. There were connections with wire nuts, coax to lamp cord, lamp cord to twin lead, etc. etc. !

    I never heard another complaint from people in that apartment complex! Your situation is not identical, but there could be some very interesting parallels in your situation!

    BTW, I was getting some noise in my cable system just during the last week or so. I got out the wrench, and checked several of the coax connections for tightness. Some were less than finger tight! All is OK now. Those things do have a tendency to loosen up over time!
  20. N0MIO

    N0MIO Ham Member QRZ Page

    A local Ham will be helping me try to do a homebrew filter using a BNC T adapter with a wire that is tuned to 146.000 to absorb and stop that signal from ever reaching the receiver.

    As to the comment earlier about my TV i am sadly running the exact same setup. A DTV box with an amplified antenna and it does it with mine 2. Also had the same problem with my last QTH in Springfield, Missouri.
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