ÉÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ» º M I C R O S C A N 1 . 3 º º º º The shareware SSTV & FAX program for the IBM-PC º º º º (c) Copyright 1994 CombiTech º º Morelstraat 60, 3235 EL Rockanje, The Netherlands º º This program may be copied in its original integral form º ÈÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍͼ TABLE OF CONTENTS 1 THE PROGRAM MSCAN 1.1 Installing the MSCAN software 1.2 Installing the Multiscan interface 1.3 Installing the Microscan interface 1.4 Screen layout 1.5 Adjusting the hardware 1.6 Computing the calibration factor 2 OPERATION 2.1 Scrolling 2.2 The endmarker 2.3 Overview function keys 2.4 Overview miscellaneous commands 2.5 Overview editor commands APPENDIX I - TECHNICAL INFORMATION A Start- and stoptones B About colours C Troubleshooting II MODE DESCRIPTION A SSTV B FAX C RTTY AND NAVTEX MSCAN 1.3 (c) Copyright 1994 CombiTech CombiTech, Morelstraat 60, 3235 EL Rockanje, The Netherlands, Tel/Fax: +311814-4252. Agents: Belgium: Spitz telecom, P. Verhaegheplein 15, 8310 Bruges, Tel: 050-353639, Fax: 050-353938 Denmark: Norad Tele-center a/s, Frederikshavnsvej 74, DK-9800 Hjírring, Tel: 98909999, Fax: 98909988 Germany: Garant-Funk, Kommerner Str. 119, 53879 Euskirchen, Tel: 02251-55757, Fax: 02251-59214 Switserland: ALINAG, Dammweg 53, 5000 Aarau, Tel: 064-227066, Fax: 064-241263 UK: AMDAT, 4 Northville Road, Northville, Bristol, BS7 ORG, Tel: 01179-699352, Fax: 01179-872228 1 THE PROGRAM MSCAN MSCAN version 1.3 is a program for receiving and transmitting SSTV and FAX images, and for monitoring RTTY, TOR-FEC and NAVTEX transmissions. MSCAN is written for the IBM-compatible PC-AT with an (S)VGA graphics adapter, and optionally a Microsoft compatible mouse. MSCAN is available in two versions: one which is used in conjunction with the Multiscan modem, and one which uses a very simple interface (Microscan). When a description in this manual is only intended for one of these versions, it is marked with '[Multi]' or '[Micro]'. Multiscan [Multi] The Multiscan modem consists of two boards (one for receiving and one for transmitting) which can be connected to each other. The receive board can also be used stand-alone. The Multiscan uses a high-quality PLL circuit for decoding and a sinewave generator for generating signals. This ensures the best pictures even under worse conditions. Microscan [Micro] This is a very simple interface circuit which consists of a single OPAMP for decoding signals. Signals are generated using the PC speaker. This interface is also known as HAMCOMM or JV-FAX interface. The Microscan version is also distributed as shareware. When a description in this manual only refers to the shareware version, it is marked with '[share]'. Some parts of this manual only apply to the receive & transmit (TRX) version of MSCAN, these parts have been marked with '[TX]'. MSCAN is a unique program. No other program offers the multitude of multitasking possibilities you will find in MSCAN. While you are transmitting or receiving a picture, MSCAN enables you to load another picture, or digitize it, and overlay it with text. To make all of this possible, MSCAN uses many of the advanced (often not used) features your computer, graphics adapter and mouse have to offer. It is therefore absolutely necessary that these parts have a high degree of compatiblity and that MSCAN will not be influenced by any other program which would be present in memory (so called resident programs). MSCAN consists of two files: MSCAN.EXE - the main program MSCAN.CNF - the configuration and registration file. 1.1 Installing the MSCAN software P.S.: If a memory manager like QEMM, EMM386 or 386MAX has been installed in your computer, then disable it first. On some PCs memory managers can greatly influence timing. This can cause MSCAN to function incorrect or even not at all! You can disable the memory manager by placing the text 'REM ' in front of where the command is placed in your AUTOEXEC.BAT or CONFIG.SYS file. Then restart your computer and run MSCAN and check its proper functioning. If all is ok, then enable the memory manager, reboot your system and run MSCAN again. If you detect any problems, or a degraded picture quality, then you cannot use this memory manager while running MSCAN. The MSCAN software is supplied on floppy disk which should be copied to the computer hard disk before use. At the DOS prompt type : MD \MSCAN CD \MSCAN Now copy the software from the distribution disk to this new directory, e.g.: COPY A:*.* Before the software can be used it must first be configured. To enter the calibration menu type: MSCAN /C followed by a . A number of questions will be asked in sequence, with each entry the current status is reported (...). If you do not want to change a parameter a simple is sufficient. Video adapter 1=VGA 2=SVGA (...) : If your computer is equipped with a standard VGA adapter, then select VGA. MSCAN will now support 16 greyshades and 16 colours. If a SVGA adapter is installed, selecting SVGA will give you 64 greyshades and 256 colours. In this case the next question will be asked: SVGA chipset 1=Trident 8800/8900 2=Trident 9000 3=ET3000 4=ET4000 5=PVGA1/WD90Cxx 6=OAK 7=Cirrus 8=VESA (...) : Select the chipset which is present on your graphics adapter. If MSCAN does not support your chipset select VESA. The following question will then be asked: 0=standard VESA 1=hybrid#1 2=hybrid#2 (...) : Select standard. If you do not get the correct image on your display, then try starting MSCAN again with the hybrid#1 and hybrid#2 settings. It is possible that your graphics adapter requires a VESA driver to be loaded in order to be VESA compatible. For the Microscan version you can now select which type of interface you want to use. RX interface 1=DTR+/RTS-/PTT 2=RTS+/DTR- (...) : For the Microscan and HAMCOMM interface select type 1. For the (older) JV-FAX interface, which has no PTT connection, select type 2. COM port 1/2 (...) : Enter the serial port number on the PC to which you have connected your hardware. Only port 1 and 2 are supported. Initial program mode 1=SSTV B&W 2=SSTV Wraase 3=New SSTV 4=BW-FAX 5=SFC-FAX 6=RTTY 7=TOR-FEC (...) Select the initial program mode. MSCAN will auto-select this mode after startup. RX display sequence 1=1 2=2 3=1&2 (...) : TX display sequence 1=1 2=2 3=1&2 (...) : [TX] These questions allow you to determine the default transmit and receive screen settings in the SSTV modes. You always can change these settings afterwards in the program using the key. Default path to picture directory : ... The default directory in which you want to store your SSTV and FAX pictures. You may choose for example the current directory (.\) or a directory named 'pictures'. Enable mouse support y/n (...) : If your mouse is not fully Microsoft compatible this may cause problems in the functionality of the program. By entering 'n' MSCAN makes no use of the mouse at all and thus it won't give you any troubles. If there is no mouse present MSCAN will detect this automatically. Crystal calibration factor (...) : Both new SSTV and FAX modes rely heavily on synchronism between transmitter and receiver, the PC has to be able to precisely set timing. Therefore you will have to calibrate the PC. The computed correction factor (see 'Computing the calibration factor') can be entered here. If you have already computed this factor for a previous version, simply enter the old factor here. Call to be transmitted (...) : [share] For the shareware version of Microscan you can now enter your callsign which is transmitted with every picture. 1.2 Installing the Multiscan interface [Multi] (text omitted) 1.3 Installing the Microscan interface [Micro] If you do not have a Microscan-like interface, you will have to build one yourself. Please refer to the Microscan schematic. Connect CN1 to the serial port of your PC (COM 1 or COM 2). Connect your receiver to 'audio in', and your transmitter (mic or line input) to 'mic input'. Connecting the PTT connection to the PTT input of your transmitter will enable MSCAN to remote control it. Now connect the two wires labelled 'speaker' to the speaker of your PC. Check the audiosignal which is applied to your transmitter and adjust its volume with R3. If the sound is weak and distorted, exchange the wires which are connected to the speaker. (drawing: interfac.txt) This interface is designed to be used with the Microscan version of MSCAN, and is equipped with a PTT connection. 1.4 Screen layout In the SSTV modes most of the screen is filled with two screens, numbered 1 (left) and 2 (right). These screens are used to display incoming and/or outgoing images. All other modes use only one big screen. Below this we find the console which consists of three parts. 1. On the left the spectrum of the current audiosignal. The spectrum contains a sync-indicator. When a correct syn- chronization is established this indicator lights up. In SSTV modes you can see three markers at the bottom of the spectrum, these mark the frequencies (from left-to-right) 1200, 1500 and 2300 Hz. In FAX modes the 1200 Hz marker is omitted since it has no function. The other two mar- kers either mark 1500 and 2300 Hz for 800 Hz shift or 1750 and 2050 Hz for a 300 Hz shift. 2. To the right the statusbars and the command field. Here all messages from the program are displayed and commands are entered. 3. At the bottom the menubar. Using displays another set of functionkeys. 1.5 Adjusting the hardware [Multi] (text omitted) 1.6 Computing the calibration factor Precise timing is vital for especially the FAX mode. A slight deviation in the crystal frequency of the PC will result in bad synchronization (picture skew) when receiving FAX stations. If you detect this picture skew when receiving 'commercial' FAX stations (i.e. calibrated stations) then the crystal in your PC will have a slight deviation. This deviation can be compensated with the calibration factor, which is entered in the configuration menu. This is done using the following method: 1. Make sure the crystal calibration factor is 0 (to be entered in the configuration menu). 2. Switch the program to FAX mode. 3. Receive a picture and make sure, using the <+> and <-> keys in the F6 menu, that the picture does not skew. 4. Compute the deviation in % of the now selected linetime by computing the difference with the normal value of the linetime and dividing this difference by the total value. The linetime can be read in the statusbar. 5. Enter this value, the calibration factor, in the configurationmenu. Example: A picture is received at 120 lpm, the linetime should be 60000ms/120lpm = 500ms. The real linetime (which you selected using the <+> and <-> keys to prevent skew) is however 499.98 ms. The calibration factor will then be: ((499.98 - 500.00) / 500) * 100% and that is -0.004%. You will enter thus -0.004. If afterwards you still detect a small skew you can adjust this by slightly changing the entered value. Make sure you use a reliable station for your calibrating. Beware that commercial stations can transmit skewed pictures, this is not caused by deviation in linetime, but simply because someone placed to chart askew in the FAX machine! A good alternative is to use a timepulse station (look around 10 MHz) which will transmit a bleep e.g. every second. These bleeps appear as small lines on your screen. When your calibration is ok, all these lines must appear directly under each other. 2 OPERATION To start the main program type MSCAN followed by . The program will enter the default mode which was defined during configuration. The program supports both operation by keyboard or by mouse. A command can be given by pressing the desired button or by positioning the mouse over the button and pressing the left mouse-button. The middle mouse-button enables you to leave a menu. The right mouse-button is equal to the key. To fully understand the operation of some functions, first the terms 'scrolling' and 'endmarker' will be explained. 2.1 Scrolling To be able to display long FAX images which could not be displayed on the standard screen size, the program uses scrolling (vertical movement), which enables the rest of the image to be shown. This scrolling is done mostly automatically. Only when the cursor is visible, no scrolling will take place (unless the cursor itself is moved). 2.2 The endmarker The endmarker is used to mark the lower border of the current image. The endmarker works mostly automatic. When a FAX image is received and reception is stopped (in auto mode this is done automatically) the endmarker will be placed at the last received line, the same is done after for example a picture is loaded from disk. Processes like transmitting or saving use the endmarker to determine the end of a picture. The endmarker is displayed as a black & white chequered line. 2.3 Overview function keys Commands which can be given using function keys are displayed in the menubar at the bottom of the screen. By pressing the key or the right mouse- button more functions will be displayed. The function of the various keys depends partly on the program mode. F1/alt-F1 Shows a context-sensitive help. Press to end. F3/alt-F3 Pictures can be printed using the alt-F3 command, at this moment only IBM- graphics compatible printers are supported. In RTTY and TOR modes the received text can be printed real-time using the F3 command. F4 Saving images to or loading images from disk in GIF format, only non- interlaced images with 16-256 colours are supported. Enter the filename or press (or right mouse button) and pick a file from the directory. Press 'delete' if you want to erase a file. If a filename was just selected it is displayed for your convenience. You may press if this is the file to be erased, or enter a new filename or press and select one from the directory. Autoload loads a picture from the auto directory, this is where pictures are saved in the FAX auto mode. The multi command shows a directory of images in FAX mode. In SSTV modes, images will be shown alternately on both screens. You can use this command during SSTV transmissions to send multiple images. For this you will have to select both screens for transmission using . After this activate the multi mode and enter the filename from which to start loading, or press and select a file from the directory. The 'box' command is used to set the box size contained within the screen. Press the left mouse button to select the top left corner, then drag the box to size and press again the left mouse button. The picture will be loaded and fits within the selected box size. The commands 'dith on' and 'dith off' activate and deactivate the dither function which creates the illusion of more colours. You can only use this function when loading original 256 colour GIF images, images which have been saved by MSCAN cannot be dithered. To write a picture to memory press 'write', to read a picture from memory press 'read'. Afterwards select desired screen (or box) and memory. Memories are non-volatile and are stored on disk. The 'path' command allows you to temporarily change the disk path used for load and save. Select 'image' to load one of the standard images for testing. alt-F4 MSCAN directly supports the high-resolution Iris truecolour videodigitizer (framegrabber). In this menu you can choose the input (composite or S-VHS/Hi- 8) and digitize the videoimage to a screen or a box with a simple push off a button, just as if you are loading a picture from disk. When in a colour mode, dithering can be used optionally. F5 Select the desired mode and its parameters. alt-F5 Select the desired program mode. This will set all parameters to default. F6 In B&W and Wraase SSTV modes this will toggle the autosync mode. This mode makes reception less sensitive to noise. By looking 'intelligent' to the synchronization of the SSTV signal, display of received images will improve under noisy conditions which is especially helpful in Wraase colour SSTV mode to prevent coloursync hickups. This mode only works when the transmitting stations have correct timing. In the New SSTV modes you can choose for 'linesync' or 'synchr'. In the linesync mode reception works just like in normal SSTV modes: every line starts after a line syncpulse. In synchrone mode reception is synchronized after the frame syncpulse. After that synchronization is crystal-controlled, just like in fax modes. In both new SSTV and FAX modes the linetime can be changed using the '+' and '-' commands. 'Clr&home' clears the screen and starts reception at the top. In FAX modes you can move the incoming line 'left' and 'right' for manual synchronization. The 'video' command allows you to invert, mirror, or convert to b&w the incoming signal. The 'auto' command activates the auto mode. In this advanced mode MSCAN automatically sets IOC, LPM and shift and detects b&w or colour transmissions. After reception the picture is saved to the auto directory with the following name format: mmddhhmm.gif (month|day|hour|minute). alt-F6 Image processing functions. You can mirror a screen, invert or move it (used to set a new top-left corner). Or you can change the colours if a picture did not start correctly in colour SSTV or FAX mode. 'Aspect' can be used to correct a picture which is received in the wrong IOC. Select 'draw' to be able to draw white (left mousebutton) or black (right mousebutton) dots on the screen. F7/alt-F7 Setting screen display sequence. All SSTV modes have two screens available for both reception and [TX] transmission. selects the screens for the current mode, for the other mode. Example: when receiving, the command <1> causes received pictures to be displayed in the left screen. By pressing <2> the right screen will be selected for transmission. The status bar will show: RX:1 TX:2. A '1&2' command selects both screens, which are then used alternating. F8 Text editor settings such as fontsize and -colour. F9 [TX] Pressing starts the transmission, pressing again will toggle auto-stop-tx (stop at end of picture or repeat). alt-F9 [TX] Switch directly between transmit and receive. When in FAX modes skip APT tones. F10 Quit program. Checks for printer spooler busy. 2.4 Overview miscellaneous commands ctrl-Home Display of received images will start at the top of the screen. This command can be given from within any menu. Ins Change colour-sequence in colour SSTV and FAX modes. Esc Leave a (sub)menu. 2.5 Overview editor commands To be able to place text in an image, MSCAN has a simple screen-editor which uses the following keys: - cursor keys: moves the cursor around - Home: moves cursor to top-left corner of screen - End: moves cursor to bottom-right corner of screen - ctrl-cursor keys: moves cursor to start or end of line - Del: clears screen, homes cursor - Tab: jumps to other screen - Backspace: deletes character left of cursor APPENDIX I - TECHNICAL INFORMATION Here is some technical info about MSCAN, and some very useful tips to solve problems. A Start- and stoptones In accordance with international standards, MSCAN uses the following start- and stoptones in b&w FAX modes: IOC start stop 288 675 Hz 450 Hz 576 300 Hz 450 Hz The colour FAX mode has been developed by radio amateurs, and as a consequence no international standard has been set. However the following start- and stoptones are semi-standard: IOC start stop 204 200 Hz 450 Hz 288 200 Hz 450 Hz Unfortunately no distinction is made for both IOCs, so MSCAN must assume 288 as a default (the starttone signals the IOC). B About colours If you have selected SVGA in the configuration menu, MSCAN will receive and transmit in 64 greyshades or 256 colours. MSCAN uses a fixed colour pallette. This means that all 256 colours are pre-determined and cannot be changed. This has many advantages but also one disadvantage. The advantages are that MSCAN can show multiple pictures at the same time and that incoming colour pictures are displayed full-colour and real-time! The one disadvantage is that some pictures, depending on the colours that are used in the picture, will not reproduce like you want them to. Although MSCAN does its best to approximate each colour, sometimes the difference will be noticeable. The solution is to use the dither option: by mixing several colours on screen, MSCAN will create the illusion of more colours. Because it can only do this if it can read the original colourvalues which are used in a picture, dithering will only work on original GIF files and on digitized images from the Iris videodigitizer. GIF files which have been saved by MSCAN already have approximated colourvalues and cannot be dithered anymore (better do it before saving). C Troubleshooting Because MSCAN is a multi-tasking program, it will take up all capacity of the PC. Therefore no extra tasks can be performed by the PC. Some problems which may occur because of this are discussed here. Use of resident programs Resident programs (permanently present in memory) occupy free memory and may cause extra system interrupts. Some caching programs for harddisk and/or floppydrives temporary disable the system interrupts. This is not allowed because this will desturb timing in MSCAN. Some memory managers (such as EMM386, QEMM or 386MAX) do an even better job in disturbing timing and may even crash the system. If you experience problems, try booting from a 'clean' DOS diskette and then start MSCAN. If there are still problems, try removing hardware (such as scanner cards) from your PC which could be generating interrupts or DMA requests. No image on the monitor Check if you have selected the correct chipset. If you choose VESA, check whether your graphics adapter requires a VESA driver to be loaded. Are you sure no memory manager or incompatible mouse is causing the problem? Printing does not work Is the printer connected to LPT1 and is it IBM graphics compatible (like IBM proprinter, EPSON FX-80 or STAR LC-10)? Program crashes immediately Try removing your mousedriver. Some mousedrivers (not the mouse itself!) like Genius seem to have some incompatibility, try loading a driver from Microsoft or Logitech. Interference in reception If loading a picture in one SSTV screen interferes with reception (or transmission) in another screen, chances are some caching program is the cause. If not, probably your computersystem is too slow. Remove all caches, memory managers etc. Use of the Multiscan modem instead of Microscan relieves the computer from one task and probably solves the problem. Else use a faster CPU or graphics adapter. If after trying the above you are still unable to get the unit to perform satisfactorily then contact your supplier who will try to help solve your problem. II MODE DESCRIPTION The Multiscan supports a number of modes. The outline specification for some of them is defined below. A SSTV SSTV pictures are transmitted only by radio amateurs. They can be received on HF (e.g. 3730 kHz LSB and 14.230 MHz USB) and on VHF (e.g. 144.500 MHz FM) and UHF frequencies. B&W SSTV SSTV is used by radio-amateurs to transmit images via a narrow (3kc) bandwidth radiochannel. The image is transmitted in lines, each line is preceded by a line syncpulse of 1200 Hz. Each image is preceded by a longer frame syncpulse of 1200 Hz. The video is modulated on a 1900 Hz carrier with an 800 Hz shift (1500 Hz is black, 2300 Hz is white). Wraase colour SSTV Derived from B&W SSTV. To be able to transmit a colour image, each line is sent three times: one for the red colours, one for the green colours, and one for the blue colours. The receiver combines the three lines to one colour line. When transmitter and receiver are not synchronized, false colours will appear at the receiver. New colour SSTV modes (martin and scotty) Instead of sending three lines, every line is divided into three parts, one for every colour. After receiving a line syncpulse, the receiver cannot be mistaking about the correct colour sequence. (pictures) These pictures show the insensibility of the new SSTV modes (here M1) to noise. Despite severe noise the synchronization is not influenced and the aspect-ratio is intact. B FAX Modulation FAX pictures on short-wave and long wave are normally transmitted in FM. That means that the transmitter is keyed between two frequencies of which the one corresponds to white, the other to black. When transmitting half tone pictures, the transmitter frequency is continuously shifted between the frequency for black and the frequency for white. Half the difference between the frequency for white and the frequency for black is called signal deviation. This deviation is, by standard, 400 Hz for short-wave and 150 Hz for long wave transmissions. Furthermore, the higher transmitter frequency should correspond to white. The shift is twice the deviation. The FAX signals should be received with an SSB receiver so that it outputs a FM-modulated audio sub carrier. This sub carrier is then fed to the interface that converts the different audio frequencies into digital intensity information that can be processed by the computer. Two terms you will have to know are IOC and LPM. IOC stands for Index Of Cooperation, which is a measure for the vertical resolution of a picture; an incorrect IOC will result in a picture which is too short or too long. The speed in which a picture is transmitted is indicated in LPM, which stands for Lines Per Minute. Automatic Picture Transmission Automatic Picture Transmission (APT) is used by commercial FAX stations to enable a fully automated unattended reception of the transmitted pictures. At the start of the transmission a start tone is transmitted for some seconds, which is recognised by the receiving unit. At the end of the transmission a stop tone is sent that switches the receiving unit back to standby mode. The tone which is sent can be used to identify the IOC of the transmitting station. Most amateurs now also use APT in their transmissions. Colour FAX By looking at colour SSTV modes, radio amateurs have developed a method of transmitting colour FAX images. Every line is sent for this purpose three times: one time for the red colours, one time for the green, and one time for the blue colours. Commercial FAX stations can be received all over the long- and shortwave bands, e.g. on 134 kHz (USB), 4778 kHz (USB) and 8145 kHz (USB). Radio amateur FAX transmissions can be received on 14.230 MHz (USB) and 144.700 MHz (FM). C RTTY AND NAVTEX If you are interested in receiving meteo information, you will be especially pleased with the combination of three modes that can be found in this program: b&w FAX, RTTY and NAVTEX. You can use the b&w FAX mode to receive weather- charts and satellite pictures, the RTTY mode (telex) to receive weather bulletins and NAVTEX (TOR-FEC) to receive all sorts of navigational warnings and information. RTTY can be received on various frequencies, though MSCAN will only decode uncoded RTTY transmissions and it will need a clean signal (two distinct bars in the spectrum). NAVTEX can be received on 516.8 kHz (USB). Radio amateurs also transmit in the RTTY mode, have a look at 145.300 MHz in FM. Enjoy MSCAN! Mike Versteeg PA3GPY CombiTech