This video can help users of Gigahertz Solutions High-Frequency Analyzers tell one type of RF radiation source from another. Here is a webpage with some RF sounds:
http://www.gigahertz.es/sonidos-generados-por-equipos-de-medicion.html
Acoustimeters also have similar sounds. Surveyed here are: Cell phone antenna at a distance, WiFi unit, cordless phone, "smart" meter, and cell phone. Do your own tests, too, to help sort out the various elements of the electro-smog soup we live in.
Where to buy:
http://www.safelivingtechnologies.ca/RF/products_rf_meters.htm
http://www.lessemf.com/rf.html
http://www.gigahertz-solutions.com/en/Online-Shop/Measurement/High-Frequency/Instruments.html
