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Computer Noise on AM radio band

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aljamri

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Hi everybody,

Computer became essential device in our life, where you find one in every 10 mtr. Being old style, AM radio fan, I always listen to my favorite programs while TicTicking on PC. This makes some loud noise on some stations ( 1000 kHz and above ).

any idea how to filter this signal out ?

Thanks
 
Make sure that all of the cover panels are securely in place on all PCs. Use connecting wiring that's no longer than necessary. Try moving processor cabinets, cables, peripherals, or the radio.
 
Make sure that all of the cover panels are securely in place on all PCs. Use connecting wiring that's no longer than necessary. Try moving processor cabinets, cables, peripherals, or the radio.
You are right, I've most of these points, and to make worse, I've got blue tooth and wireless mouse. But I can't avoid using any of them.

Any other idea?

Thanks
 
See if you can listen to your favourite station online.

I had the same problem with FM until I discovered I could listen to it on my PC.
 
It's a sinister plot, I tell you. The computers are taking over. First they tell us to abandon getting bills in the mail box so we have to use a computer to pay the electric bill . Then they interfere with radios, both AM and FM so we have to use a computer to listen to music. What next?
 
A high quality receiver with a coax input for antenna connection (instead of a built-in ferrite loop), nand then use a remote (far away from the computers). AM-FM-Stereo radios like would be dash mounted in a car work well for this...
 
Keep the radio away from your PC.

The words high quality and AM radio don't belong in the same sentence. Providing your Internet connection is fast enough, most digital stations are higher quality than AM.

If you don't have a fast enough connection or your radio station doesn't stream via the Internet, you can connect your radio's headphone socket to the line in socket on the back of your sound card and have the radio as longer distance away as possible. When I used to be on metered dial-up, I used to have my radio on upstairs, in me bedroom and ran a cable downstairs to my computer where it plugged into the sound card. I could listen to any station, AM or FM, without interference and I could record the radio on my PC.
 
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Hi everybody,

Computer became essential device in our life, where you find one in every 10 mtr. Being old style, AM radio fan, I always listen to my favorite programs while TicTicking on PC. This makes some loud noise on some stations ( 1000 kHz and above ).

any idea how to filter this signal out ?

Thanks

You have to get away/very far from any SMPS or any circuitry that can influence AM reception....best suggestion is time-out on a farm with wide open spaces. And not a computer or any Mains driven equipment anywhere in sight.
 
Hi,


This is not only a problem with PC computers, but also with microcontrollers. I had a radio/charger that came with a cordless drill a while back where the charger did not work right so i designed a uC chip into the circuit to charge correctly and monitor the battery status. That killed the AM reception on many channels.
Didnt try to eliminate or reduce the problem though as i dont listen to AM anyway.
 
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As others have indicated, there may not be much you can do about much of the noise. You have to prevent it from being radiated at the source and if you don't own the source then there is not much you can do about it.

In this area I have friends who enjoy baseball, NASCAR races and other programming that is offered by select AM broadcast stations. Usually these stations are in smaller cities and run at lower power. We've used tuned loop antennas with amplifiers to improve the reception and quality. No, it will not ever be great but if it's the only way to get a ball game, car race, etc it's better than nothing.

The tuned loop has two distinct advantages - it offers some gain (with the amplifier it's better) and it has a distinct and very sharp null. The null attenuates the signal in a particular direction. Sometimes you can null the interference allowing improved reception of the desired signal.
 
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The tuned loop has two distinct advantages - it offers some gain (with the amplifier it's better) and it has a distinct and very sharp null. The null attenuates the signal in a particular direction. Sometimes you can null the interference allowing improved reception of the desired signal.

Same applies to an AM portable or table-top radio that has a ferrite loop-stick type of antenna. It is sometimes possible to orient the radio so as to null the interference while still being able to receive the desired station.
 
I have no data but only experience to suggest that the performance of an 18 inch square tuned loop far exceeds that of built in loopsticks but if and only if the tuned loop is located well away from metal.

In my workshop with lots of stuff around the loop works ok. On the second floor of my house with less metal around (but still the house wiring, overhead lamp, etc) it worked better. Outside on a picnic table it performed incredibly well. Advice from some suggests mounting on rooftop away from metal - not an easy thing for most people. I do know some people have fashioned tuned loops from ferrite rods, somewhat larger than is standard. It's possible that the larger loopstick or even a standard mounted more remotely with an amplifier can improve reception. Still, it's an awful lot of work for moderate improvement.
 
Most interference is amplitude fluctuations.
An AM radio picks up nothing but interference because the "A" in AM stands for AMPLITUDE. A half-decent FM radio ignors amplitude fluctuations, has a much higher frequency where there is less interference, is hi-fi and is in stereo.
 
Most interference is amplitude fluctuations.
An AM radio picks up nothing but interference because the "A" in AM stands for AMPLITUDE. A half-decent FM radio ignors amplitude fluctuations, has a much higher frequency where there is less interference, is hi-fi and is in stereo.
All very true...... the listener must use an AM receiver if that's where the program is. Many of us no longer have perfect hearing like yours (the races don't help) so it's OK with us when AM is used for voice instead of music. Fortunately for us NASCAR fans most races are on the net.
 
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All very true...... the listener must use an AM receiver if that's where the program is. Many of us no longer have perfect hearing like yours (the races don't help) so it's OK with us when AM is used for voice instead of music. Fortunately for us NASCAR fans most races are on the net.

I can still hear normal high frequencies. AM radio and the telephone sound awful to me because the important high frequency consonants of speech and the harmonics of music are missing. Now my favourite News TV show is eliminating all the important high frequency consonants from their broadcast. Their sound guy must be deaf.
 
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