Editing TV and FM DX (section)

{{Short description|Long-distance reception of signals on the VHF frequency band}}{{More citations needed|date=May 2025}}[[File:Antenna-178969.jpg|right|thumb|amateur HF/UHF radio antenna]]
[[File:Antennes uhf.JPG|right|thumb|amateur UHF radio antenna]]
'''TV DX''' and '''FM DX''' refer to the active search for distant [[radio station|radio]] or [[television station]]s received during unusual atmospheric conditions. The term [[DXing|DX]] is an old [[telegraphy|telegraphic]] term meaning "long distance."

[[very high frequency|VHF]]/[[ultra high frequency|UHF]] television and radio signals are normally limited to a maximum "deep fringe" reception service area of approximately {{convert|40|-|100|mi|km|lk=on}} in areas where the broadcast spectrum is congested, and about 50 percent farther in the absence of interference. However, providing [[anomalous propagation|favourable atmospheric conditions]] are present, television and radio signals sometimes can be received hundreds or even thousands of miles outside their intended coverage area. These signals are often received using a large outdoor [[antenna (radio)|antenna]] system connected to a sensitive TV or FM receiver, although this may not always be the case. smaller antennas and receivers, such as those in vehicles, will receive stations from farther away than usual depending on how favourable conditions are.

While only a limited number of local stations can normally be received at satisfactory signal strengths in any given area, tuning into other channels may reveal weaker signals from adjacent areas. More consistently strong signals, especially those accentuated by unusual atmospheric conditions, can be achieved by improving the [[television antenna|antenna system]]. The development of interest in TV-FM DX as a [[hobby]] has grown over time, with enthusiasts installing and upgrading HF/UHF antennae for the purpose of gaining a higher range. The TV-FM DX hobby is similar to other radio/electronic related hobbies such as [[amateur radio]], [[MW DX|Medium Wave DX]], or [[short-wave radio]]; and organisations such as the Worldwide TV-FM DX Association have developed to coordinate and foster the further study and enjoyment of VHF/UHF television and FM broadcast DX.<ref>[http://anarc.org/wtfda Official WTFDA Club Website] {{Webarchive|url=https://web.archive.org/web/20030621134535/http://www.anarc.org/wtfda/ |date=2003-06-21 }}</ref>