The AM DX hobby goes back to the first days of radio. No doubt the first question the budding transmitter designers and builders asked was "How far does this thing get out?". So, people were out there with their homebuilt receivers trying to answer that question. Marconi got across the Atlantic. Fessenden broadcast to ships far out in the ocean. Later transmitters were more powerful, and receivers improved, all in the name of trying to increase the distance a signal could be heard.
Early listeners sent "Reception Reports" which, if correct, were rewarded with a QSL, or verification of reception. Other things like Ekko stamps were added. Engineers looked forward to receiving these reports. The furthest got the bragging rights with their peers, and management could impress their advertisers.
The hobby thrives to this day, with a dedicated cadre of enthusiasts using a whole new collection of equipment and techniques. Computer-based receivers, flag directional antennas, various filters and tuners are employed. Computers keep recorded files of the whole AM band for later DXing. E-mail based lists provide up to the minute tips of what stations are being heard. Propagation forecasts help with predicting expected conditions.
It's been interesting to see that IBOC on AM hasn't been at all popular. The interference it's caused has been detrimental to DXing.
|Last update: 21 January 2012|