What Causes Radio Noise Interference and Annoying Buzzes
Sometimes you might experience interference and annoying radio noise or buzzing while listening on the AM band in particular. The question is, what causes that?
Tip: A very good battery operated portable AM radio is great for preparedness.
Causes of AM Radio Noise Interference
A list from C.Crane, maker of one of the best long-range AM radios
| Dimmer switch (even in ceiling fans) | Touch lamp (even when turned off) |
| Fluorescent light bulbs | Fluorescent tubes |
| Incandescent bulb that is about to burn out | LED light bulb (non-FCC certified types) |
| Automatic on/off night lights | Automatic outdoor yard lights |
| Christmas tree lights & other blinking bulbs | Faulty electrical switches |
| Electronic bug and pest controllers | Ultrasonic motion detectors |
| Electric blankets | 120VAC smoke detectors (battery operated OK) |
| 12VDC inverters | Smart-meters from electric company |
| Streetlights | Dirty insulators and transformers on nearby power pole |
| Nearby televisions or monitors | Cable or satellite boxes |
| Ionic Breeze® or other electrostatic air purifier | CPAP machines |
| Smart speakers | Cordless phones (2.4GHz) |
| Scanners | Treadmills |
| Appliances with motors | Modems and/or routers |
| Desktop Computer or Laptop | Tablet or Smartphone |
| Cell phone chargers | Switching AC adapter |
How To Eliminate Radio Noise and Interference
The most obvious solution is to turn off the offending device.
Temporarily switch the radio from AC power to battery power to see if the interference is coming from the electrical outlet. If the noise stops, a Radio Noise Filter/Surge Protector (view on amzn) can dramatically reduce the interference.
Turn off all circuit breakers to see if the noise stops. If it does, then you know it is something in your house. Turn on one circuit at a time to isolate what area the noise is coming from.
Use a battery-operated radio as a direction finder. Turn the radio until the loudest noise is heard. The front and back of the radio will usually point to the noise origin.
Carry a battery-operated radio around the neighborhood paying attention to where the noise may be coming from.
If a power pole is suspected, call the utility company. They will usually check the area. Sometimes it’s from a transformer. I’ve also heard that it may have something to do with the insulators.
I have had the best success finding the source (sources) of AM radio band interference by simply using a small portable AM radio as a direction finder. Tune the radio to a frequency with no station (just noise). Then walk around until it gets louder – until you have pretty much determined where it’s coming from.
One of my biggest sources of interference in my home is the solar power system inverter (48V DC battery bank to 120 VAC house power). If I really want to spend a little time during an evening tuning in distant stations, I’ll just shut it off for awhile.
CCRadio 2E by C.Crane
Here’s a picture of my C.Crane AM Radio:
What a great AM radio! The audio is tuned for the spoken word. Sounds great! The “2E” model is especially good for long distance tuning.
[ Read: Best AM Radio for DX Long Range Listening ]
[ Read: Best Cheap Portable Pocket AM/FM Radio ]