F2 Skip
Don't hold your breath for this one, but
be aware of its potentialities. This is the familiar long-haul skip which
bounces shortwave signals around the world in hops of roughly 2000 miles each.
During sunspot peaks F2 may extend up to 60 MHz, opening American channel 2 to
DX, plus a number of European, African and Oceanic TV stations operating at
these frequencies and below. F2 activity is greatest in years of peak sunspot
activity. As sunspot activity increases, F2 MUF also rise. F2 at VHF
frequencies is not probable in years of low solar activity. If you want to
keep track of F2 conditions, which tend to peak in the spring and fall,
monitor on a 30-50 MHz radio. Paging stations beyond 1600 miles or so on 35
and 43 MHz will give you a warning when F2 is "up".
Note that some foreign TV audio
transmission is AM, unlike North America where FM audio is used. North
American DX'ers should check during the morning hours when it is noon, or
slightly after noon, at the midpoint of the path to Europe. F2 is a daytime
propagation at these frequences, directly depending on solar radiation. F2 may
have a very sharp MUF, hovering just below or on channel 2 for long periods.
So on your radio, keep a check on known TV audio and video carrier frequencies
below channel 2. Beware of false signals if radiation near these last
frequencies are from your own or nearby TV sets! On a radio, video sounds like
a rough buzz. On a TV, video propagated by F2 is rarely clear; though it may
be strong, it will be heavily smeared.
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