TV DXing
TV DXing and FM DXing are similar in that they both typically involve receiving distant signals via tropospheric ducting and sporadic E-skip.
When a temperature inversion occurs in the troposphere, it can act as a duct, which causes VHF and UHF waves that encounter the duct to travel along it for significant distances before they return to the earth's surface. Television signals can travel along a tropospheric duct for hundreds of miles until the signals escape the duct and return to the earth's surface.
Sporadic E-skip is another fairly common method of long-distance TV signal propagation. It occurs when a TV signal bounces off a highly ionized patch of the atmosphere's E layer and returns to earth some 500-1,500 miles from the transmitter. The summer months are best for E-skip propagation.
Your chances of successful TV DXing are best on analog channels 2-13 because they use frequencies conducive to long-range propagation. You can verify a distant station by channel identification information or newscasts being broadcast on the channel.
Analog TV DXing is possible with a rabbit-ear antenna, but an external directional antenna such as a Yagi design provides better reception of distant signals.
Digital TV DXing is a growing hobby, but participation is limited due to the high cost of digital television.
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