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- F2_propagation abstract "The E layer of the ionosphere is not the only layer that can reflect VHF television signals. Less frequently, the higher F2 layer can also propagate VHF signals several thousand miles beyond their intended area of reception.Solar activity has a cycle of approximately 11 years. During this period, sunspot activity rises to a peak and gradually falls again to a low level. When sunspot activity increases, the reflecting capabilities of the F1 layer surrounding earth enable high frequency short-wave communications. The highest-reflecting layer, the F2 layer, which is approximately 200 miles (320 km) above earth, receives ultraviolet radiation from the sun, causing ionisation of the gases within this layer. During the daytime when sunspot activity is at a maximum, the F2 layer can become intensely ionized due to radiation from the sun. When solar activity is sufficiently high, the MUF (Maximum Usable Frequency) rises, hence the ionisation density is sufficient to reflect signals well into the 30 – 50 MHz VHF spectrum. Since the MUF progressively increases, F2 reception on lower frequencies can indicate potential low band 45-55 MHz VHF TV as well as VHF amateur radio paths. A rising MUF will initially affect the 27 MHz CB band, and the amateur 28 MHz 10 meters band before reaching 45-55 MHz TV and the 6 Meter amateur band. The F2 MUF generally increases at a slower rate compared to the Es MUF.Since the height of the F2 layer is some 200 miles (320 km), it follows that single-hop F2 signals will be received at thousands rather than hundreds of miles. A single-hop F2 signal will usually be around 2,000 miles (3,200 km) minimum. A maximum F2 single-hop can reach up to approximately 3,000 miles (4,800 km). Multi-hop F2 propagation has enabled low-band VHF reception to over 11,000 miles (17,700 km).Since F2 reception is directly related to radiation from the Sun on both a daily basis and in relation to the sunspot cycle, it follows that for optimum reception the centre of the signal path will be roughly at midday.The F2 layer tends to predominantly propagate signals below 40 MHz, which includes the 27 MHz CB band, and 28 MHz 10-metre Amateur radio band. Less frequently, television and amateur signals in the 45 – 55 MHz VHF band are also propagated over considerable distances. In North America, F2 is most likely to only affect VHF TV channel 2.Television pictures propagated via F2 tend to suffer from characteristic ghosting and smearing. Picture degradation and signal strength attenuation increases with each subsequent F2 hop.".
- F2_propagation wikiPageExternalLink dx_faq.htm.
- F2_propagation wikiPageExternalLink tropo.html.
- F2_propagation wikiPageExternalLink lasereme.htm.
- F2_propagation wikiPageExternalLink channels_2-6.html.
- F2_propagation wikiPageExternalLink tvfmlog.html.
- F2_propagation wikiPageExternalLink rdsdx.
- F2_propagation wikiPageExternalLink listinfo.
- F2_propagation wikiPageExternalLink fmdx.
- F2_propagation wikiPageExternalLink kw4rz.
- F2_propagation wikiPageExternalLink index.html.
- F2_propagation wikiPageExternalLink radioprop.htm.
- F2_propagation wikiPageExternalLink antenna.
- F2_propagation wikiPageExternalLink www.dxfm.com.
- F2_propagation wikiPageExternalLink gallery.
- F2_propagation wikiPageExternalLink www.fmdx.altervista.org.
- F2_propagation wikiPageExternalLink www.fmdx.it.
- F2_propagation wikiPageExternalLink www.fmlist.org.
- F2_propagation wikiPageExternalLink www.fmscan.de.
- F2_propagation wikiPageExternalLink dx.html.
- F2_propagation wikiPageExternalLink tech_burst_tech.aspx.
- F2_propagation wikiPageExternalLink www.mixture.fr.
- F2_propagation wikiPageExternalLink K1MOD.
- F2_propagation wikiPageExternalLink index.php?PHPSESSID=4024ec296a6162577b43581f30c19c02&board=301.0.
- F2_propagation wikiPageExternalLink www.skywaves.info.
- F2_propagation wikiPageExternalLink www.ukdx.org.uk.
- F2_propagation wikiPageExternalLink www.wtfda.info.
- F2_propagation wikiPageExternalLink www.wtfda.org.
- F2_propagation wikiPageID "14393992".
- F2_propagation wikiPageLength "7688".
- F2_propagation wikiPageOutDegree "31".
- F2_propagation wikiPageRevisionID "581920156".
- F2_propagation wikiPageWikiLink 10-meter_band.
- F2_propagation wikiPageWikiLink 6-meter_band.
- F2_propagation wikiPageWikiLink Amateur_radio.
- F2_propagation wikiPageWikiLink BBC.
- F2_propagation wikiPageWikiLink Brisbane.
- F2_propagation wikiPageWikiLink Category:Ionosphere.
- F2_propagation wikiPageWikiLink Category:Radio_frequency_propagation.
- F2_propagation wikiPageWikiLink Citizens_band_radio.
- F2_propagation wikiPageWikiLink Clear-channel_station.
- F2_propagation wikiPageWikiLink Crystal_Palace_transmitting_station.
- F2_propagation wikiPageWikiLink Federal_Standard_1037C.
- F2_propagation wikiPageWikiLink Hampshire.
- F2_propagation wikiPageWikiLink Holme_Moss.
- F2_propagation wikiPageWikiLink Ionization.
- F2_propagation wikiPageWikiLink Leeds.
- F2_propagation wikiPageWikiLink MW_DX.
- F2_propagation wikiPageWikiLink Norwich.
- F2_propagation wikiPageWikiLink Perth.
- F2_propagation wikiPageWikiLink Radio_propagation.
- F2_propagation wikiPageWikiLink Skywave.
- F2_propagation wikiPageWikiLink Solar_cycle.
- F2_propagation wikiPageWikiLink Southern_California.
- F2_propagation wikiPageWikiLink Sun.
- F2_propagation wikiPageWikiLink Sunspot.
- F2_propagation wikiPageWikiLink Sussex.
- F2_propagation wikiPageWikiLink TVQ.
- F2_propagation wikiPageWikiLink TV_and_FM_DX.
- F2_propagation wikiPageWikiLink Television.
- F2_propagation wikiPageWikiLink Ultraviolet.
- F2_propagation wikiPageWikiLinkText "F2".
- F2_propagation wikiPageUsesTemplate Template:Audio_broadcasting.
- F2_propagation wikiPageUsesTemplate Template:Citation_needed.
- F2_propagation wikiPageUsesTemplate Template:Cite_web.
- F2_propagation wikiPageUsesTemplate Template:Main.
- F2_propagation wikiPageUsesTemplate Template:See_also.
- F2_propagation subject Category:Ionosphere.
- F2_propagation subject Category:Radio_frequency_propagation.
- F2_propagation type Physic.
- F2_propagation type Plasma.
- F2_propagation type Thing.
- F2_propagation comment "The E layer of the ionosphere is not the only layer that can reflect VHF television signals. Less frequently, the higher F2 layer can also propagate VHF signals several thousand miles beyond their intended area of reception.Solar activity has a cycle of approximately 11 years. During this period, sunspot activity rises to a peak and gradually falls again to a low level.".
- F2_propagation label "F2 propagation".
- F2_propagation seeAlso Tropospheric_propagation.
- F2_propagation sameAs Q17011551.
- F2_propagation sameAs m.05t0z1v.
- F2_propagation sameAs Q17011551.
- F2_propagation wasDerivedFrom F2_propagation?oldid=581920156.
- F2_propagation homepage www.fmdx.it.
- F2_propagation isPrimaryTopicOf F2_propagation.