Hello to my fellow hamateur radio and SWL radio enthusiasts around the world.
Welcome to my abbreviated
“not for profit” daily HF radio wave
propagation forecast and solar, space and geomagnetic weather
discussion.
If you find this "not for profit" daily HF radio wave
propagation forecast and solar, space and geomagnetic weather discussion useful
to your hamateur and SWL radio activities, feel free to drop me a line and let
me know that at
thomasfgiella@gmail.com .
Feel free without prior
permission to redistribute this "not for profit"
daily HF radio wave
propagation forecast and solar, space and geomagnetic weather discussion, as
long as you redistribute it in its entirety and
give me credit for
it.
Supporting images associated with my "not for profit" daily HF radio
wave propagation forecast and solar, space and geomagnetic weather discussion
can be found in my Facebook account at
https://www.facebook.com/thomasfranklingiellaw4hm
and
at
http://lists.contesting.com/mailman/listinfo/spaceweather but without
supporting images.
It's a NO SPAM "opt" in email type group hosted by
contesting on line (COL), so you have to sign up by using an existing email
address and creating a password.
And last but not least I also post some
snippets of solar, space and geomagnetic weather goings on and images in my
Twitter account at https://twitter.com/GiellaW4hm
.
---------------------------------------------------------------------------------------------------------------------
#234
Issued on Tuesday August 22, 2017 at 2330 UTC
Global Daily HF Radio Wave
Propagation Forecast-
HF radio wave propagation condition-
A
deteriorated state.
HF radio wave propagation trend-
A
deteriorating state.
NORTHERN HEMISPHERE RADIO WAVE
PROPAGATION
80-60 (75-60) meters- poor at night and very poor at
day, 40-30 (41-25) meters- fair at
night and poor at day,
20-17 (22-16) meters- fair at night and fair at
day, 15 (13) meters- poor
at night and fair at
day, 12-10 (11)
meters- very poor at night and very poor at day.
Keep in mind that almost
daily during the northern hemisphere summer season you will find that the 10
(11) meter bands will open via short north-south and east-west propagation paths
via sporadic E (Es). Also when multiple sporadic E (Es) clouds form and line up
favorably much longer propagation paths open up on east-west paths. And last but
not least north-south propagation paths occur across the equator via trans
equatorial propagation (TEP).
SOUTHERN HEMISPHERE
RADIO WAVE PROPAGATION-
80-60 (75-60) meters- fair at night and poor at day,
40-30 (41-25) meters- fair at night and fair at day,
20-17 (22-16)
meters- very poor at night and fair at day,
15 (13) meters- very poor at
night and poor at day,
12-10 (11) meters- very poor at night and very poor at
day.
Received RF signal strength scale-
Very Good- +1 over S9 Or
Greater
Good- S7-9
Fair- S4-6
Poor- S1-3
Very Poor- S0
Meter
Band Equivalents
Ham & SWL
160-> 90
80->
75
60-> 60
40-> 49, 41
30-> 31, 25
20->
22, 19
17-> 16, 15
15-> 13
12,10-> 11
We are now
firmly in summer/winter solstice type of HF radio wave propagation
conditions.
This means generally poor HF radio wave propagation conditions in
the northern hemisphere especially at day and generally good HF radio wave
propagation conditions in the southern hemisphere especially at
day.
Globally HF radio wave propagation conditions are most evenly
balanced
during the fall and spring equinoxes and most diametrically opposed
during
the summer and winter solstice.
Conditions change daily,
weekly, monthly, yearly and by decade, as the
sun rises and sets at
different times and at different angles from the
ecliptic, as well as by
radio wave frequency. This is due to changes in the
maximum usable frequency
(MUF), lowest usable frequency (LUF) and F layer
critical frequency
(FoF2).
---------------------------------------------------------------------------------------------------------------------
This
HF Radio wave propagation forecast is produced based on the SIGINT_CAP HF radio
wave propagation prediction software. I wrote it beginning in the late 1980’s
but I’m sorry to say that it can’t be distributed to the general
public.
And though this HF radio wave propagation forecast is produced
based on the SIGINT_CAP, I do check the actual band conditions at my location in
the USA and tweak the forecast manually where and when necessary. I also check
global HF radio wave propagation conditions via remoted radio receivers around
on every continent of the globe and tweak the forecast manually if and when
necessary.
The hamateur radio JT65A mode RF signal levels received are
based on 5 watts and ½ wave dipole up at 40 feet.
The hamateur radio
PSK31 mode RF signal levels received are based on 25 watts and ½ wave dipole up
at 40 feet.
The hamateur radio CW mode RF signal levels received are
based on 50 watts and ½ wave dipole up at 40 feet.
The hamateur radio SSB
RF mode signal levels received are based on 100 watts and ½ wave dipole up at 40
feet.
The HF shortwave broadcast band AM Mode RF signal levels are based
on 100,000 watts (100 kw) and a typical VOA type curtain array
antenna.
Please keep in mind that this is a relatively simplified HF
radio wave
propagation forecast, so as to keep it easily understandable and
applicable by the average radio enthusiast.
Globally HF radio wave
propagation conditions are most evenly balanced
during the fall and spring
equinoxes and most diametrically opposed during
the summer and winter
solstices.
Conditions change daily, weekly, monthly, yearly and by
decade, as the
sun rises and sets at different times and at different angles
from the
ecliptic, as well as by radio wave frequency. This is due to
changes in the
maximum usable frequency (MUF), lowest usable frequency (LUF)
and F layer
critical frequency (FoF2).
The D and E layers also come
into play through RF radio wave signal
absorption and refraction. And then
there is sporadic E (Es) radio wave
propagation that can really throw a
wrench into the gears so to speak.
Things like sporadic E (Es) radio wave
propagation and lightning storm
static can impact HF radio wave propagation
in an unpredictable manner and
mostly bad.
Ongoing solar, space and
geomagnetic weather goings on also impact HF radio
wave propagation
conditions in a negative
manner.
---------------------------------------------------------------------------------------------
As
we move forward towards the next solar minimum between solar cycle #24
and
#25 the number of days with a 0 daily SSN will steadily increase.
Eventually
every day for many, many, many months will see a 0, the big goose
egg.
In 2008 I forecasted solar cycle 24 to be the weakest in the
past 100 years
and that forecast verified. I also forecasted that solar
cycle 25 would be
virtually nonexistent, similar to the Dalton type solar
minimum that
occurred in the early 1800's.
Other than sunspot
magnetic polarity it will probably be very difficult to determine when solar
cycle 24 ended and solar cycle 25
began.
---------------------------------------------------------------------------------------------------------------------
GENERAL
GUIDELINES CONCERNING CORRELATION OF PROPAGATION INDICES TO ACTUAL HF
PROPAGATION CONDITIONS-
NOTE!!! The propagation indices "interpretations"
are my personal
intellectual property. Therefore the radio wave propagation
indices
interpretations contained herein is copyrighted © 1988-2017 by
Thomas F.
Giella, W4HM, all rights reserved. Reproduction of information
herein is
allowed without permission in advance as long as proper credit is
given.
All 14 of the following indices have to occur as described below
in order to
see the best global high frequency radio wave propagation
possible,
something that happens rarely.
1.) Dropping geomagnetic
field indices numbers are better, Kp of 0 best.
2.) A daily sunspot
number of 150 or higher, 200 or higher best.
3.) A daily sunspot number
of greater than 100 for routine stable formation
of the E Valley/F Layer
ducting mechanism.
4.) Previous 24 hour Ap index under 10, fewer than 7
for several days
consecutively are best.
5.) Previous 3 hours Kp
index fewer than 3 for mid latitude paths, fewer
than 2 for high latitude
paths, 0 for several days consecutively is best.
6.) Energetic protons no
greater than 10 MeV (10+0).
7.) Background x-ray flux levels greater than
B1 for several days
consecutively, greater than C1 best.
8.) No
current STRATWARM alert.
9.) Interplanetary magnetic field (IMF) Bz with
a (positive number) sign,
indicates a lesser chance of high latitude path
aurora
absorption/unpredictable refraction or scattering of medium frequency
RF
signals, when the Kp is above 3.
10.) A -10 or better towards a
positive number Dst index during the recovery
time after a geomagnetic
storm, as related to the equatorial ring current. A
positive number is
best.
11.) Rising positive T index number. The T Index tracks with the F2
layer
critical frequency (foF2) and sunspot number (SSN) and indicates the
capability of the F2 layer to refract RF signals.
12.) Galactic
cosmic rays decrease to -3 units below zero and trending
towards
zero.
13.) Energetic electron flux levels no greater than 2 MeV
(2+0).
14. A solar wind speed of less than 300 km/s for several days
consecutively.
------------------------------------------------------------------------------------
Standard
Disclaimer-
Note! I use error prone RAW public domain data from the NOAA
Space
Environment Center, other U.S. government entities and educational
institutions, to produce my comprehensive HF radio wave propagation
forecast. This data is gathered and made public by the U.S. Government using
taxpayer $$$ (including mine).
However the solar, space and
geomagnetic discussions as well as the HF propagation forecast that I produce
from the RAW public domain
data is my personal intellectual property.
Therefore the solar, space and geomagnetic weather discussions and HF radio wave
propagation forecast contained herein is copyrighted © 1988-2017 by Thomas
F. Giella, W4HM.
Feel free without advanced permission to
redistribute this "not for profit"
solar, space and geomagnetic weather
discussion and HF radio wave propagation forecast, as long as you redistribute
it in its entirety and
give me credit for it.
Also solar, space and
geomagnetic weather forecasting is still an inexact
science. The forecasts
are not official but for educational and hobby
related purposes only and are
subject to human error and acts of God,
therefore no guarantee or warranty
implied.
