Vince_Condella's Blog

I vividly remember as a kid growing up in the Chicago suburbs being in my room in the evening and picking up long-distance radio stations on my little AM transistor radio.  It fascinated me to listen in to WWL in New Orleans, WSB in Atlanta, or WWVA in Wheeling, West Virginia.  These were powerful transmitting radio stations that suddenly came in clearly on many nights.

I went through a similar experience driving in my car this evening.  It was 6:45 p.m. and as I went up and down the AM dial I could clearly hear WSB in Atlanta, then WABC 770 out of New York City broadcasting the New York Rangers hockey game.  Another click down the dial brought in the sounds from Detroit talk radio WJR.  This was cool stuff and brought me immediately back to Lombard, Illinois and an 8-year-old nerdy kid.  I would write to these faraway radio stations, tell them the time and programming I heard so I could prove to them I actually heard them, and they would send me a cool 3 x 5 postcard with the station's call letters and city of origin.  (These are called QSL cards)  I would proudly hang these cards up on the bulletin board in my rooom right next to the Bobby Hull autographed photo and the White Sox line-up from the Chicago Tribune sports section.

An example of a QSL card commonly used by Amateur Radio (HAM) operators.

I didn't know it at the time, but our ability to hear AM radio stations long distance is due to ionospheric refraction.

If an AM radio station transmits a powerful signal, e.g. 50,000 watts or higher, it may refract (bend) off of the ionosphere hundreds of miles above the Earth.  This is called a Sky Wave.  (The ionosphere is a layer of charged particles surrounding the Earth)  Radio stations also transmit a Ground Wave, but this doesn't travel far, perhaps 50 to 100 miles depending on the station's power.

Many AM radio stations only transmit during daylight hours and power down at night.  This allows the more powerful stations to come through loud and clear.

Talk about a flashback to the days of my youth!  That ride in the car this evening took me back 45 years.