Topband: Summer Propagation
KN4LF, Thomas Giella
kn4lf@tampabay.rr.com
Sat, 28 Jul 2001 15:02:58 -0400
Yes 160 meter propagation does exist in northern hemisphere summer but
it's still way down compared to winter, especially below approximately 32
deg north lat. on NE-E paths to Europe and north Africa and NW-W paths to
Asia, as the sun is at a higher angle at our latitude and therefore D layer
absorption higher. Shorter nights and longer days also mean longer time
periods of D layer absorption.
Even in winter as AA4MM and KK4TR can attest to, the path from Florida to
Europe and North Africa opens last here or sometimes not at all, well after
states to our NE have an open path. Many times we have heard stations in
Georgia working Europe and not just W8JI, when we could not here a peep here
at 28 deg. north lat. Sometimes it's D layer absorption and sometimes the
160 European signal falls out of the E-F layer duct to our NE and just dies.
Conversely we have an advantage into the Caribbean, Central America, South
America in summer and winter due to a shorter propagation path and we also
get into Australia pretty easily in our northern hemisphere winter due to
antipodal focusing!
73,
Thomas Giella, KN4LF
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