Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.1 6/24/83; site mgweed.UUCP
Path: utzoo!watmath!clyde!burl!we13!mgweed!rjr
From: rjr@mgweed.UUCP (Bob Roehrig)
Newsgroups: net.ham-radio
Subject: arrl propagation forecast bulletin nr 15
Message-ID: <8380@mgweed.UUCP>
Date: Mon, 9-Apr-84 19:13:49 EST
Article-I.D.: mgweed.8380
Posted: Mon Apr  9 19:13:49 1984
Date-Received: Wed, 11-Apr-84 00:25:42 EST
Organization: AT&T Consumer Products - Montgomery Illinois
Lines: 38


qst de k9eui
hr propagation forecast bulletin nr 15  from arrl headquarters
newington ct  april 8, 1984
to all radio amateurs  bt

sunspot numbers and the solar flux have been  falling  steadily
since  the  end  of  march.  the visible portion of the sun was
almost devoid of spots at bulletin time.  the  solar  flux  was
down to 101, and it is expected to drop further in the next few
days.  these conditions will make for lower f  layer  muf  than
would  normally  occur  at  this  season.   seasonal  and solar
effects will be most noticeable on 21 and 28 mhz.  skip will be
poorer  on all frequencies, and the number of useable hours per
day will go down.

the good side of this picture is that, with a quieter sun,  the
quality and strength of signals will improve, though the useful
day is shorter. geomagnetic activity was above normal  much  of
the  time recently, and conditions tended to be below normal on
all frequencies.  we  are  also  moving  into  the  season  for
sporadic  e propagation, which enlivens the 28 and 50 mhz bands
at this time of year.  characteristics to be expected are  very
high  signal levels at times, but with frequent changes in skip
distance and direction.  there  have  been  phenomenal  e  skip
sessions on 50 mhz, and linkages of this mode with the seasonal
transequatorial propagation have provided exciting 50  mhz  dx.
in  the  southern part of the country, 50 mhz was active nearly
every day since the middle of march.  on  april  5  and  6  new
zealand,  australia  and  several  small  pacific  islands were
worked on 50 mhz from most u.s.  call  areas.   obviously,  the
transequatorial  mode  does not require high solar flux levels.
watch for it in the afternoon hours on  days  when  the  wwv  k
index is 3 or higher.

american sunspot numbers for march  29  through  april  4  were
between 63 and 118 with a mean of 89.1  ar