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- 900227.23:07 ral hfmagic1.doc
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- HF MAGIC VERSION 1.0 DOCUMENTATION
-
-
- 1. INTRODUCTION
-
- HF MAGIC 1.0 is an HF propagation prediction program which is
- different from those available from other sources today. This program
- is designed for use by the amateur or shortwave listener who wants to
- maximize communications over "practical" HF distances, generally up to
- 2500 miles in length. It not only presents the maximum usable
- frequency (MUF), which is only part of the story, but computes the
- received signal strength in "S" units including the very important
- contribution of "D region absorption". This factor is often missing
- from propagation models, but is very important in determining total
- signal strength during the daytime hours. The program is based on
- MINIMUF and NBS absorption expressions.
-
- The outstanding features of this program include very compact
- size and rapid execution.
-
-
- 2. PROGRAMS
-
- The program package consists of 4 files:
-
- HFMAGIC1.FNL main BASIC program
-
- MAGICSRC.BAT batch for screen output
-
- MAGICFIL.BAT batch file to send output to a file
-
- MAGICPRT.BAT batch file to send output to line printer
-
- The version which provides only screen output can be directly
- executed by entering the command: BASICA HFMAGIC.FNL . The file
- version will load the output into a file A:MAGICOUT.FIL; you can edit
- the batch file MAGICFIL.BAT to create the output file on any desired
- drive or directory.
-
-
- 3. INPUT DATA REQUIRED
-
- The program will issue prompts for all required data.
-
- The first prompt will be for which version of the program is
- desired; enter 1 if you desire S-meter predictions for the 5
- traditional ham bands (80,40,20,15, and 10 meters); enter 2 if you
- desire 9 bands (5 traditional plus 160, 30, 18, and 12 meters); enter 3
- if you desire the computation for arbitrary frequencies which you can
- input; and enter 4 if you are only interested in MUF predictions.
-
- The next prompt will ask for the number of solar flux points
- and increment. This permits you to have multiple runs which can be
- referred to in order to evaluate the best band to use for a particular
- set of solar flux conditions. If only a single run is desired, enter
- 1,1 at this prompt.
-
- The next prompt will ask for the number of runs to be
- executed. If you desire computations for more than 1 set of
- conditions, enter the appropriate number here else 1 for only a single
- set of conditions.
-
- The fourth prompt will ask for the details for the path being
- computed. This data should be entered with a comma between each number
- as a delineator. The data consists of the latitude and longitudes of
- the two endpoints of the path (in degrees and decimal degrees, north
- and west positive), day of the month as a number, month as a number,
- the starting value of solar flux (if multiple flux values are being
- computed, else the particular flux value desired for the computation),
- and a field of alphanumeric characters to document the run (these will
- be printed out on the output). Current values of solar flux can be
- determined by listening to station WWV or WWVH (2.5,5,10,15,20 Mhz) at
- 18 minutes past the hour.
-
- After completion of the data entry, the entered parameters
- will be echoed back for confirmation. Hit enter if the string is
- correct.
-
- 4. OUTPUT
-
- The output will consist of a matrix of time, frequency, and
- signal strengths (in dB over/under S-9) based on the assumption of 100
- watts transmitted and the use of non-directive antennas such as
- vertical and dipole antennas. A value of -98 in the output indicates
- that the band will not be open, and a value of -99 indicates very high
- D-region absorption. The normal range of useful communications will be
- down to an amplitude of -54, corresponding to 54 dB below S-9, or S-0
- (an S unit is 6dB by convention). An output of 20 indicates a signal
- level of 20dB over S-9.
-
- The time presented is Universal Time (UT), based on the local
- time at the prime meridian at Greenwich, England. Remember to convert
- this time to your local time.
-
-
- 5. ACCURACY
-
- Most people who have used this program have reported that the
- predictions match the actual conditions with a reasonable degree of
- accuracy in predicting the best band to use and the signal strengths
- which will result. The accuracy is quite good for distances up to
- about 2500 miles.
-
-
- 6. COMPENSATION
-
- Disemmination of this program via BBS systems is encouraged
- so that many people can use it. If you feel that this program is
- useful for you, please send a token fee ($10 suggested) to:
-
- Dick Lodwig W2KK 2201 Duvall Rd. Woodbine, Md. 21797
-
-
- 7. EXAMPLE OUTPUT
-
- An example output for the case of a Maryland to Florida path
- on the 27th of February with a solar flux of 200 is provided below.
- Note that for communicating at midnight Eastern time (5 UT), the 160
- thru 30 meter bands will give a path, but since the atmospheric noise
- is much larger for the lower bands, the 40 or 30 meter bands will give
- the best results.
-
- For communicating at noon Eastern time (17 hrs UT), the 20
- thru 12 meter bands will all give equivalent results and the choice of
- band can be made based on equipment capabilities and QRM observed on
- the bands.
-
- ------------------------------------------------------------------------
-
-
- ENTER:
- 1-5 VAL SM
- 2-9 VAL SM
- 3-ARBITRARY SM
- 4-3 VAL MUF
- ? 2
- ENTER NUM OF SF PTS,INCREMENT
- ? 1,1
- NUMBER OF RUNS
- ? 1
- STR FORMAT LAT,LON,LAT,LON,DAY,MO,SF START,ALPHA TITLE
- ENTER STRING NO. 1
- ? 39,77,23,80,27,2,200,Md-Fla
-
- FLUX PTS,INCR 1 1
- INPUT DATA STRINGS
- 39 77 23 80 27 2 200 Md-Fla
-
- PRESS ENTER TO CONTINUE?
-
- HFMAGIC 1.02 FOR Md-Fla BY W2KK.
-
- DATE: 27 FEB
- TRANSMITTER LOCATION
- LATITUDE 39 LONGITUDE 77
- RECEIVER LOCATION
- LATITUDE 23 LONGITUDE 80
- SUNSPOT NUMBER= 155 SOLAR FLUX= 200 (WWV AT HR+18 MIN)
-
-
- RECEIVED SIGNAL FOR 100W TRANSMITTED. PERFECT
- NON DIRECTIVE ANTENNAS. DB OVER/UNDER S9
-
- UT FREQUENCY
- HR MUF 1.9 3.8 7.2 10.1 14.2 18.1 21.3 24.9 28.5
- -- --- ---- ---- ---- ---- ---- ---- ---- ---- ----
- 0 20.4 19 13 7 5 2 -1 -98 -98 -98
- 1 17.8 19 13 7 5 2 -98 -98 -98 -98
- 2 16.3 19 13 7 5 2 -98 -98 -98 -98
- 3 15.0 19 13 7 5 2 -98 -98 -98 -98
- 4 13.9 19 13 7 5 -98 -98 -98 -98 -98
- 5 13.0 19 13 7 5 -98 -98 -98 -98 -98
- 6 12.3 19 13 7 5 -98 -98 -98 -98 -98
- 7 11.7 19 13 7 5 -98 -98 -98 -98 -98
- 8 11.1 19 13 7 5 -98 -98 -98 -98 -98
- 9 10.7 19 13 7 5 -98 -98 -98 -98 -98
- 10 10.4 19 13 7 5 -98 -98 -98 -98 -98
- 11 13.0 -4 7 6 4 -98 -98 -98 -98 -98
- 12 19.2 -99 -21 -2 -0 -1 -2 -98 -98 -98
- 13 22.6 -99 -54 -11 -5 -3 -3 -4 -98 -98
- 14 24.7 -99 -85 -20 -9 -5 -5 -5 -98 -98
- 15 26.2 -99 -99 -27 -13 -7 -6 -6 -6 -98
- 16 27.2 -99 -99 -32 -16 -9 -7 -6 -7 -98
- 17 27.7 -99 -99 -35 -17 -9 -7 -7 -7 -98
- 18 28.0 -99 -99 -34 -16 -9 -7 -7 -7 -98
- 19 27.9 -99 -99 -30 -15 -8 -6 -6 -6 -98
- 20 27.4 -99 -99 -24 -11 -6 -5 -5 -6 -98
- 21 26.6 -99 -69 -15 -7 -4 -4 -5 -5 -98
- 22 25.3 -99 -37 -6 -2 -2 -3 -4 -4 -98
- 23 23.4 -54 -5 2 2 0 -1 -3 -98 -98
-
- GRT CIR DIST= 1800 KM 1125 STAT MILES 978 NAUT MILES.
- PATH MIDPOINT= 78.6 LON 31 LAT
-
- HFMAGIC 1.0 COPYRIGHT W2KK 2201 DUVALL RD. WOODBINE, MD 21797
- ---------------------------------------------------------------------
-