Libris Britannia 4/science library(b).zip/science library(b)/HAM_RAD/3926.ZIP/SSTVFAX4.DOC

Text File | 1993-01-21 | 6KB | 141 lines

    WELCOME TO THE SSTV AND FAX PROGRAM SSTVFAX4 VERSION 4.45

                        AUTHOR:ON5KN BBS @ON7RC-5
                            BELGIUM

    ***THIS IS NOT A PERFECT PACKAGE AND WILL NEVER BE***

    THIS IS AN EXPERIMENTAL RECEIVE AND TRANSMIT PROGRAM WRITTEN IN
    ASSEMBLER AND TO USE ON ANY IBM COMPATIBLE UNDER MSDOS

    THE UPSET WAS MADE TO BE ABLE TO RECEIVE AND TRANSMIT SSTV AND
    FAX WITH A MINIMUM OF ADDITIONAL EXTERNAL HARDWARE

    FOR RECEPTION OF BOTH MODES YOU ONLY NEED A SIMPLE 741-IC
    TRANSMITTING ONLY 4 RESISTORS AND 2 CAPACITORS ARE NEEDED

    RECEIVE HARDWARE IS POWERSUPPLIED BY THE RS232 FROM THE PC

    THE SCHEMATICS ARE ADDED IN THE FILE SSTVFAX4.SCH WICH YOU
    SIMPLY CAN PRINT UNDER MSDOS ON    A GRAPHICS PRINTER
    USAGE: COPY SSTVFAX4.SCH PRN /B

    THE INTERFACE IS BUILD WITHOUT ANY ADJUSMENT COMPONENT AND
    DOES NOT REQUIRE ANY ADJUSTMENT
    ALTHOUGH THE OUTPUT LEVEL TO YOUR TX-INPUT CAN BE ADAPTED
    TO YOUR NEED BY CHANGING THE VALUE OF R4 (22K)
    A 16-LEVEL GREYSCALE IS AUTOMATED ON TOP OF EACH SSTV PICTURE

    SSTV CAN BE RECEIVED FROM ALL ACTUAL PRESENT MODES HOWEVER
    THE IMAGES WILL BE DISPLAYED IN GREY-LEVELS EVEN FOR COLOUR
    SENDED PICTURES
    TRANSMISSION OF SSTV IS POSSIBLE IN 16 GREY-LEVELS AND IN
    FOUR STANDARD MODES 8SEC, 16SEC, 32SEC,(NORMAL) AND 64SEC
    (IN DOUBLE MODE)
    INITIAL FORMAT IS 8SEC
    WHEN POINTING THE UPPER-LEFT CORNER YOU ARE FREE TO CHOICE
    THIS POINT ANYWHERE ON THE SCREEN
    WHEN POINTING THE BOTTEM-RIGHT CORNER ACCEPTING THE MOUSE
    POSITION WILL KEEP A 1 TO 1 RATIO
    MOVING THE MOUSE ON BOTTEM-RIGHT WILL REDUCE OR ENLARGE THE
    TRANSMITTED PORTION OF THE SCREEN ALTHOUGH MAINTAINING IT
    IN THE SELECTED MODE BUT TRY TO DISPLACE DIAGONALLY

    FAX WILL BE RECEIVED AND TRNSMITTED IN 60,90,120,180,240,
    AND 480 LPM IN IOC 288 AT NORMAL AND IN IOC 576 IN DOUBLE
    480 LPM WILL GIVE YOU DRAFT QUALITY
    TRANSMISSION OF FAX WILL SEND EACH LINE TWICE IN NORMAL AND
    FOUR TIMES IN DOUBLE
    IN FAX THE FORMAT FUNCTION WILL SELECT THE PORTION OF SCREEN
    WICH WILL BE TRANSMITTED IN A 1 TO 1 RATIO
    ON STARTING UP THE PROGRAM SSTVFAX4.COM YOU MAY ADD A TIMING
    CORRECTION PARAMETER I.E.   SSTVFAX4.COM 2\E\-30
    THE 2 = COM PORT IN USE (MAY BE 1 OR 2)
    THE E = EGA VIDEO MODE (MAY BE C, H, E, OR V)
    THE -30 = TIMING CORRECTION FOR FAX (MAY BE FROM +99 TO -99)
    TO DETERMINE THIS FACTOR TWO WAYS OF DOING
    THE DIFFICULT ONE IS RECEIVING A FAX OF WICH YOU ARE SURE OF
    ACCURACY AND TRY AND CORRECT IN STEPS
    THE EASY WAY IS TO LOCATE YOUR PC-OSCILLATOR ON 14MHZ BAND
    THE STANDARD IS 1.193.180 HZ * 12 = 14.318.160 HZ
    SO YOU MAY EXPECT TO FIND IT BETWEEN 14.300 KHZ AND 14.340 KHZ
    RECEIVE IT USING A SHORT WIRE FROM THE ANTENNA TO THE PC
    AND READ THIS FREQUENCY AS F0 IN HZ
    DIVIDE FO BY 240 GIVING F1
    SUBSTRACT FROM 59.682 THIS F1 GIVING THE TIMING CORRECTOR AND SIGN
    AS AN EXAMPLE YOUR ZEROBEAT IS 14.330.880 HZ AS F0
    THIS GIVES US 14.330.880 / 240 = 59712 AS F1
    AND 59.682 - 59.712 = -30 AS CORRECTION FACTOR
    EVEN A READING ERROR OF 1.000 HZ WILL GIVE A GOOD APPROACH

    THE RECEPTION SCREEN CAN BE ONE OF THE CURRENT MODES EXCEPT
    S-VGA WICH IS NOT YET SUPPORTED

    SOME VIDEO CARDS MAY NOT BE COMPATIBLE

    IN SSTV BEST SYNC WILL BE OBTAINED WHEN RIGHT BOTTOM OF IMAGE
    IS POINTED WITH RIGHT MOUSE BUTTON

    START POINT OF IMAGE ON SCREEN CAN BE REDEFINED WITH MOUSE-
    POINTING AND LEFT MOUSE BUTTON

    ON SOME MODES OF COLOUR SSTV IT MAY BE INTERESTING TO USE
    DOUBLE COMPACTATION

    ON RECEPTION OF 96 SEC OR MORE IMAGES USE OF "U" TO DISABLE
    VERTICAL SYNC UNTIL NEXT "T" AVOID SPURIOUS SYNC BY QRM

    AS TIMING IS CRITICAL ON SUCH AN APPLICATION THE POSSIBILITIES
    ARE FUNCTION OF THE SPEED OF YOUR PC AND TYPE OF SCREEN

    THE PROGRAM WAS WRITTEN ON  AT 286/12MC 640K  VGA 256K

    MAINLY CGA AND HERCULES MODES ARE NOT QUALIFIED BUT CAN BE
    BE USED WITH LIMITED RX-ONLY FUNCTIONS

    A LOWER SPEED LIMIT IS BUILT-IN ON THE START-UP AND IF BELOW
    PROGRAM WILL ABORT

    THE MINIMUM MEMORY SPACE REQUIRED IS 400KB IF BELOW PROGRAM
    WILL ABORT ON START

    A FEATURE WICH EXPANDS THE POSSIBILITIES IS A STANDARD
    MOUSE WITH MOUSE-DRIVER

    THE BUILT-IN SCAN FUNCTION IS BASED ON THE GENIUS GS-4500
    THE SSTVFAX4 PROGRAM DRIVES DIRECTLY ITS INTERFACE CARD
    AND CONVERTS ITS BLACK AND WHITE DOTS TO A 16 GREY LEVEL
    THE AMOUNT OF FREE MEMORY DETERMINES THE MAXIMUM SCAN-LENGHT
    BEST RESULTS ARE OBTAINED IN HORIZONTAL SCANNING AND EGA

    ALL PICTURES CAN BE STORED ON AND RETRIEVED FROM DISK IN
    GIF87a FORMAT. THE 4-GREY-PLANES FORMAT OF SSTVFAX3 AND
    SSTVFAX2 IS STILL SUPPORTED FOR LOADING PICTURES.

    IF YOUR SYSTEM IS EQUIPED WITH ANOTHER SCANNER YOU ARE ABLE
    TO CREATE YOUR OWN PICTURES AND IMPORT THEM AS GIF-FILES

    MAKING SLOWSCAN AND FAX ON A REAL LOW-BUDGET WAS THE
    MAIN TARGET OF THIS PACKAGE BY INTRODUCING THESE MODES OF
    RECEPTION AND TRANSMISSION AS A SIMPLE ADD TO THE BECOMING
    COMMON-USE-PC IN THE RADIO-AMATEUR WORLD

    TRY FIRST THE RECEPTION MODULE !
    IT IS EASY AND YOU WILL SEE THE ACTIVITIES ON HF AND VHF
    NEAR 14.230KHZ YOU ARE SURE TO SEE THEM FIRST

    ENJOY THIS FREE SOFTWARE PACKAGE AND LET ME KNOW WHAT YOU
    ARE THINKING ABOUT AND GIVE SOME SUGGESTIONS
    MAKE REFERENCE TO SSTVFAX4 VERSION 4.45

    IF YOU MAKE A COPY FOR FURTHER DISTRIBUTION PLEASE LEAVE IT
    IN THE SELF-EXPLODING FORM SSTVFAX4.COM OR AT LEAST BE SURE
    THAT IT INCLUDES SSTVFAX4.TXT/SSTVFAX4.SCH/SSTVFAX4.EXE
    AND THIS SSTVFAX4.DOC FILES

    LAST REMARK ... YOUR TIMER MAY BE DISTURBED AFTER RUNNING
    SSTVFAX4 JUST TILL ANOTHER START-UP OF YOUR PC

    HAVE A LOT OF FUN AND SEE YOU SOON ON THE BANDS
                73 ON5KN BBS @ON7RC-5 BELGIUM