Topband: Difference in Annual Propagation

[Herb Schoenbohm]

Topband Dx-ers have discussed the difference in topband propagation
during the various changing seasons for as long as I can remember but
apart from the increased summertime thunderstorm static I never heard
the difference express in db. The statement "The difference between
summer minimum and spring and fall maximums (there is another dip in the
middle of winter) is about 15 db at 500Khz and reduces to 3 db at 1700
kHz." is from a series of papers on propagation, antenna modeling,
ground wave and sky wave prediction methods available for your viewing
in .pdf form at http://www.its.bldrdoc.gov/pub/pubs.html.  The documents
were prepared for the NTIA as part of a program for the ATIS (Advanced
Traveler Information System) which plans for medium wave usage up to
1705 Khz.  There is a treasure trove of valuable information available
for download that relates to topband technology in so many ways. Some of
the data is for the ITS (Intelligent Traveler Information System) which
will use the spectrum adjacent to topband to notify rural travelers of
road conditions, road hazards, weather and incident reporting.

Plenty of great stuff about both ground wave and sky wave propagation.
Let me know if it is of use to you.

Herb Schoenbohm
Box 4419
Kingshill, VI
00851


--
FAQ on WWW:               http://www.contesting.com/topband.html
Submissions:              topband@contesting.com
Administrative requests:  topband-REQUEST@contesting.com
Problems:                 owner-topband@contesting.com