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Discussion Starter · #1 ·
I know this is mainly a computer site, but I thought some of you propeller-heads (and I use that term lovingly!) might know about electronics in general.

I suspect that someone in my neighborhood is operating electronic equipment that interferes with my radio (AM broadcast - - lower end of band).

The station will be coming in clear as a bell - - then without me moving the radio or making any change at all, some heavy interference comes in (as if someone threw a switch!). After interfering for hours it will also vanish just as suddenly.

Question is: how do I handle it? If I report it to the FCC (or some other agency) will they even take notice of a single complaint?

I don't see how they can track this guy down unless they sit in my neighborhood at night with sophisticated direction-finding equipment.

Doesn't even happen every night. I'm sure it would be expensive for them to station people sitting there with equipment hoping to get lucky on a particular night.

So what can I do? Any way for me to track down what is happening personally?

Need some advice here.
 

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Hmmm when I was younger, a neighbor had a Ham Radio set up that would affect our TV reception. What he was doing was perfectly legal, he was supposed to monitor his interference I believe. :(

Not sure what would be causing your problem, but I have had a similar problem here recently. I was blaming it on solar flairs. :eek:
 

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Discussion Starter · #3 ·
I sent an Email to the FCC to see what they would say. They'll get back to me.

Bassetman said that the TV interference was legal. Doesn't seem right to me, but in this crazy day and age, who knows?

That's why I'm trying to get information. I'm not even sure that it IS illegal - - it may be my tough luck that I can't get reception. Or, it may be some Bozo who is doing something that he is not supposed to do.
 

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I would suspect John Ashcroft is monitoring you! :D
 

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Wino said:
I would suspect John Ashcroft is monitoring you! :D
Wino we all knew that! ;)

DN the guy was supposed to have his antenna aimed in a way as to not interfere with the neighbors TVs. However this was in the 60's and early 70's when we all got our TV by air waves (not cable) and the government wasn't as likely to care if your neighbor was bothering you with something that was legal.
 

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DNeurococo said:
I suspect that someone in my neighborhood is operating electronic equipment that interferes with my radio (AM broadcast - - lower end of band).
Need some advice here.
My advice? Quit listening to those damn socialist stations broadcasting from Cuba with their 1950's equipment. Need anymore advice? ;)
 

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You need to determine what type of interference it is and whether it is really "radio" interference or power line interference. Get a portable, something battery powered, and go outside. Do you still hear it? If you only hear it with the radio which is AC powered, then the interference is coming through the power line. Many types of electrical equipment produce it including outdoor lights.

Do you hear voices? (no not the schizo kind). If yes take a look around the neighborhood for someone with a Ham radio or CB tower. There's your culprit. Go have a talk with them, there are filters they can use to minimize the problem.
 

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When I lived in East Anglia (south east England), we would get a half hourly flypast by squadrons of around half a dozen F4 Phantoms from our local airbase. The combination of vibration caused by all that jet propulsion and static from the planes control surfaces used to cause near whiteout on all the local TV sets. Should someone have reported it to the broadcasting authority, who in turn would pay the USAF a visit? (Maybe even get them to invoice by proxy for a lot of laundry bills, as the jettisoned avgas would float down onto local washing lines)
 

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Discussion Starter · #10 ·
Lighthouse: The interference lasts for quite a long time, so I don't think it is a fly-by (unless they are circling my house - - waiting for orders to strike!).

Rollin’Rog: I haven’t tried putting the radio on batteries or taking it outside - - will give it a try the next time I experience static.

Also, I do NOT hear voices. What I hear is very strange. Like the electrical equipment in Frankenstein’s laboratory or the noises in the background of the “Outer Limits” TV show. Sort of like a low pitched whistle that goes higher and higher until it is almost painful to listen to, combined with some crackling noises - - but no voices. Happens with different radios. Goes down a little bit if I hold the radio at all sorts of weird angles or de-tune it from the proper frequency.

There is a microwave telephone relay station nearby. Could that be the culprit? I thought micro was a different frequency from AM, but maybe their equipment is leaking off different frequencies due to a disorder. Just guessing here.

Thanks for the tips. Keep them coming. I’ll report back with taking the radio outside on battery power.
 

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I get this all the time on my old time (pre-1940?) radio which gets shortwave and am. Likely, it's somebody's vacuum cleaner or electric drill or something. Actually, even just turning on our floor lamp causes a low level of static.

Don't get this as bad with our modern radio's am band but get some. Station distance seems a bigger factor here. FM's OK though.
 

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Not sure how to prevent the interference. Maybe there's a way to "shield" the power cable? Of course, if it is microwave sourced, I suppose you would need some sort of filter. I have googled but don't get much addressing this simple problem. Here's something a bit techy but interesting:

Understanding and preventing radio frequency interference
William (Bill) L. Mostia, Jr., P.E. Amoco Corp.
Control Engineering Europe
July 1, 1998



Radio-based devices such as walkie-talkies and pagers have been used in our plants for many years but in recent years there has been an increased number of radio frequency sources both inside and outside our facilities. This combined with the greater clock speed of our microprocessor-based systems and increased use of digital communication systems complicates the electromagnetic environment in our facilities.

Our instrumentation systems must be able to function in the presence of high-frequency interference which is commonly referred to as radio frequency interference (RFI). It is also sometimes referred to as electromagnetic interference (EMI), though this is somewhat of a misnomer as EMI covers a wider range of frequencies.

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RFI can be defined as objectionable high-frequency electromagnetic radiation where the source is further away than the radiation's wavelength (l) divided by 2p, i.e. l/2p.

The area past this distance is called the far field and the radiation is called a plane wave. Shorter than this distance is called the near field and electric or magnetic fields will dominate the interference coupling mechanism. The effectiveness of coupling RFI into a system is a function of the radiating source, its strength, the characteristics of the transmission path, the distance involved, and the sensitivity of the receiver.

Four basic methods can minimize RFI effects:

* Eliminate the radiating source;
* Shield either the source or the receiver;
* Separate distance; and
* Improve circuit design.

The basic method for getting rid of a RFI source is to remove the radiating mechanism. Conversion of electromechanical contacts, for example, to solid state would remove the arc-generated RFI. Electrostatic discharge (ESD) generated RFI could be reduced by removing the charge generating mechanism or by providing a method to bleed off the charge.

Shielding is probably the most common means used to reduce the effects of RFI. Shielding can work both to prevent RFI from radiating out or to prevent RFI from getting in. The effectiveness of a shield is a function of the material, the frequency, the angle of incidence, coverage, and the thickness of the material. Metal is commonly used to shield RFI. Plastic materials used as shields are coated or impregnated with reflective and adsorptive materials or have embedded screens.

Often it is the enclosure openings, seams, and joints that are the limiting factors of the shield's effectiveness. The longest dimension of any opening should be less than l/20. Reduction in opening dimensions, screens, coatings, and special gasketing are some of the methods used to prevent RFI from getting into or out of enclosures. Cables in metal conduit are generally protected against RFI, but cables in a cable tray may open up windows of exposure. The effectiveness of cable shields such as aluminum foil, braided, and coaxial is a function of the material, frequency, thickness, and the shield coverage.

Distance can be used to provide separation between RFI generating equipment and the sensitive equipment by reducing the field strength of the RFI at the receiver. Administrative controls can also be used to prohibit RFI sources from being operated near sensitive equipment.

Circuit design can also help. Some common techniques used to minimize the effects of RFI include component location, conductor lengths, and component selection as well as the use of differential inputs, twisted pair cabling, common mode chokes, and ferrite beads.

RFI will be an increasing concern in the future. A good reference in this area is the book: Noise Reduction Techniques in Electronic Systems by Henry W. Ott.
RFI Terms

EMI: Electromagnetic interference, electrical interference from electric, magnetic, or plane wave fields.

ESD: Electrostatic discharge, the discharge of free electrons from an insulator to a conductor or to another insulator.

Far field: The area away from a receiving device greater than the incident radiation's wavelength divided by 2p.

Near field: The area nearer to a receiving device less than the incident radiation's wavelength divided by 2p.

Plane wave: Electromagnetic radiation where the source is further away than the radiation's wavelength divided by 2p.

RFI: Radio Frequency Interference, electromagnetic radiation where the source is further away than the radiation's wavelength divided by 2p, which is generally in the range of a few 100 kHz to the GHz.

Shield: A material placed between unwanted electromagnetic fields and a receiving or transmitting device with the purpose of minimizing the transmission of the electromagnetic fields past the shield.
 

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Microwave intereference is generally too high for AM radio, but can in some cases affect the FM band which includes TV audio. I do believe Microwave ovens, however, can be a source as they can disrupt the AC powerline, but the actual microwave radiation does not interfere with AM.

Electrical, CB and Ham radio can all affect AM. Electrical usually produces a buzzy static. I get it on AM most of the night from the local outdoor lights which come on at dusk; it goes off as soon as they do at day break; for some reason it has a periodic character, running for about 15 seconds out of every minute, possibly due to a timer that regulates it. But it will not rise to a high pitched whine. Batteries and moving the radio to a different location is the best way to determine what is causing it. AM interference that is local is usually pretty easy to isolate.

Actually your description, now that I think about it, reminds me of the type of interference I used to hear when I designed circuits that built up a capacitive charge for flash devices such as strobes. The low pitched whine occurs at the beginning of the charge cycle and keeps rising until the circuit is fully charged.
 

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Let's take a sanity moment here. No disrespect to DN but in his "profile" he has listed himself as independently wealthy and no longer has to work. Yet he is here asking us to help him solve a problem with an AM Radio! (which I didn't know they even made anymore). Hey buddy, rather then spend hours checking up on your neighbors and buying batteries and using different power outlets and on and on just buy a new fricken' AM radio and move on. If your life is currently spent fixated on the AM radio problem then we really need to get you a new life. In all honesty, there is nothing at the low end of the AM dial worth listening to anyway.
 

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Discussion Starter · #17 ·
Well, the radios that have this problem are good radios. One is a Sony ICF 4-Band. Another is a Sangean CC-Plus radio. Happens with several other radios - - so my being a cheapskate and not having a good radio is not the source of the problem.

As far as AM being not worth listening to - - I should remind GB that his drug-taking hero Rush Limbaugh is heard on AM! But that's not the point! How would you like it if I sat outside your house jamming TV/Radio that you listen to, then defended myself by saying, "well, that stuff is not worth listening to anyhow"!

I thought that one way I might "buy my way out" of this problem is to get satellite rado: XM or Sirius - - but I don't know too much about it. Do they re-broadcast regular AM stations?
 

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Yeah, and what about us ye olde radio collectors, gb?

Listening to a neighbor's power tools through his garage is one thing but when it interferes with a neighbor's enjoyment of a hobby, it's another.

BTW, if ever we have an emergency which requires us to listen to radio signals from a long distance, our FM frequencies won't be worth much. Living as I do a bit remote from the smoke, I don't find FM to be perfectly reliable in the signal strength department.

SW is similarly affected by RFI. Both am and short wave are most effective over long distances. And my old am radios mostly are set up to receive short wave as well.

I guess in an emrgency there may not be much left to cause RFI, however. But you may want to get thee to a SW or AM radio, preferably charged by winding.

:rolleyes:
 

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First, it was a joke.

Second, you are not allowed to collect anything if you continue to spell old "olde". Do you buy your collectibles at the shoppe?

DNeurococo said:
As far as AM being not worth listening to - - I should remind GB that his drug-taking hero Rush Limbaugh is heard on AM! But that's not the point! How would you like it if I sat outside your house jamming TV/Radio that you listen to, then defended myself by saying, "well, that stuff is not worth listening to anyhow"!
I can say with all honesty that I don't think I've ever heard Rush Limbaugh speak. I don't even know were his radio program is located. Hell, I don't remember the last time I listened to AM radio. And despite your protests listening to "Evening Chats with Fidel" or "Uncommon Sense with Norm" doesn't qualify as necessary listening.
 
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