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╔════════════════════════════════════════════════════════════╗ ║ M I C R O S C A N 2 . 0 ║ ║ ║ ║ The shareware SSTV & FAX program for the IBM-PC ║ ║ ║ ║ (c) Copyright 1995 CombiTech ║ ║ Morelstraat 60, 3235 EL Rockanje, The Netherlands ║ ║ This program may be copied in its original integral form ║ ╚════════════════════════════════════════════════════════════╝ To enable printing to any kind of printer, all special printer codes except formfeed (12), and all graphic symbols and pictures have been removed from this document. Some codes have been replaced with the following text: {up} arrow up symbol {down} arrow down symbol This document is formatted to be printed double-sided, with 58 lines per page. Every new page is preceded by a formfeed. Type the following command to print this manual: PRINT MSCAN-EN.DOC TABLE OF CONTENTS ================= 1 INSTALLATION . . . . . . . . . . . . . . . . . . . . . 1 1.1 Installing the MSCAN software . . . . . . . . . . . . 1 1.2 Installing the Multiscan interface . . . . . . . . . 4 1.3 Installing the Microscan interface . . . . . . . . . 4 1.4 Adjusting the hardware (Multiscan only) . . . . . . . 6 1.5 Computing the calibration factor . . . . . . . . . . 8 2 OPERATION . . . . . . . . . . . . . . . . . . . . . . . 9 2.1 Screen layout . . . . . . . . . . . . . . . . . . . . 9 2.2 Selecting the program mode . . . . . . . . . . . . . 10 2.3 Loading and saving pictures . . . . . . . . . . . . . 10 2.3.1 Setting the path . . . . . . . . . . . . . . . . . 10 2.3.2 Loading a picture from disk . . . . . . . . . . . . 11 2.3.3 Loading a picture from the auto directory . . . . . 12 2.3.4 Loading a picture from memory . . . . . . . . . . . 12 2.3.5 Loading a standard image . . . . . . . . . . . . . 12 2.3.6 Loading a picture from the Iris videodigitizer . . 13 2.3.7 Saving a picture to disk . . . . . . . . . . . . . 13 2.3.8 Saving a picture to memory . . . . . . . . . . . . 14 2.4 Text editor . . . . . . . . . . . . . . . . . . . . . 14 2.5 Receiving and transmitting pictures . . . . . . . . . 15 2.5.1 Receiving pictures in SSTV modes . . . . . . . . . 15 2.5.2 Transmitting pictures in SSTV modes . . . . . . . . 17 2.5.3 Receiving pictures in FAX modes . . . . . . . . . . 18 2.5.4 Transmitting pictures in FAX modes . . . . . . . . 21 2.6 Processing pictures with the toolkit . . . . . . . . 22 2.7 Managing the spectrum . . . . . . . . . . . . . . . . 22 APPENDIX I - TECHNICAL INFORMATION . . . . . . . . . . . 25 III A Start- and stoptones . . . . . . . . . . . . . . . . . 25 B Troubleshooting . . . . . . . . . . . . . . . . . . . . 25 APPENDIX II - MODE DESCRIPTIONS . . . . . . . . . . . . . 27 A SSTV . . . . . . . . . . . . . . . . . . . . . . . . . 27 B FAX . . . . . . . . . . . . . . . . . . . . . . . . . . 28 MSCAN 2.0 Copyright 1995 CombiTech CombiTech, Morelstraat 60, 3235 EL Rockanje, The Netherlands, Tel/Fax: +311814-4252. Agents: Australia Kevin Cavanagh VK4SP, 222 Brisbane Valley & New Zealand Highway, Wanora, Queensland 4306, Tel/Fax: +61-74-643954 Belgium Spitz telecom, P. Verhaegheplein 15, 8310 Bruges, Tel: 050-353639, Fax: 050-353938 Denmark Norad Tele-center a/s, Frederikshavnsvej 74, DK-9800 Hj rring, 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 United Kingdom AMDAT, 4 Northville Road, Northville, Bristol, BS7 ORG, Tel: 01179-699352, Fax: 01179-872228 The Graphics Interchange Format(c) is the Copyright property of Compuserve Incorporated. GIF(sm) is a Service Mark Property of Compuserve Incorporated. IV 1 INSTALLATION MSCAN 2.0 is a program for receiving and transmitting SSTV and FAX images. For convenient operation, MSCAN 2.0 requires an IBM-compatible computer with at least a 80386 processor, SVGA video capable of displaying in truecolour and a Microsoft compatible mouse. MSCAN is available in two versions: one for the Multiscan modem, and one for the Microscan modem. 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 multi- tude 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 1 MSCAN to function incorrect or even not at all! You can dis- able 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 <Enter>. 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 <Enter> is sufficient. SVGA chipset 1=Trident 8900D 4=ET4000(VESA) 5=PVGA1/WD90Cxx 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. [Multi] For the Multiscan the next question will appear: Spectrum calibration factor low (...) : Spectrum calibration factor high (...) : If you have a previous version of MSCAN, enter the same values here which are displayed in the configuration menu of your previous version. The calibration factors are used for the calibration of the spectrum, and interrelated to this the 2 calibration of the demodulator. If a ready built unit has been bought the figures will already have been entered for your interface. They should not be changed unless the unit is to be recalibrated. Unless you need to change these values simply press <Enter>. [Micro] 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=B&W-FAX 5=Colour FAX (...) : 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 receive and transmit screen settings in the SSTV modes. You can always change these settings afterwards in the program itself. 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'. Crystal calibration factor (...) : Both new SSTV and FAX modes rely heavily on synchronism between transmitter and receiver, for this 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. 3 1.2 Installing the Multiscan interface [Multi] First install the Multiscan interface by connecting it to a suitable radio and to an unused serial port on the PC. Radio connections Pin 1 - transmit audio (connect to MIC input of transmitter) Pin 2 - ground connection Pin 3 - receive audio (connect to audio output of receiver) Pin 5 - PTT (connect to PTT of transmitter) Computer connections Pin 2 - Receive Data from Multiscan Pin 3 - Transmit Data to Multiscan Pin 5 - ground 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 schema- tic. 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 wire labelled 'speaker' to one of the speaker terminals of your PC. Connect the wire labelled 'ground' to the chassis of the PC. Check the audiosignal which is applied to your transmitter and adjust its volume with R3. If the sound is weak and distorted, connect the 'speaker' wire to the other speaker terminal. 4 DEMODULATOR =========== RS-232 PC (25p) (9p) │ /│ ┌────┤< ├────■ DTR (20) (4) │ │ \│ │\│ ││100n 3│ \7 1N4148 audio ■──┬──┤├───┬──────────┤ \ 6 in │ ││ │ │741>■─────────■ DSR (6) (6) │ ┌┴┐ ┌────┤ / │ │ │ │ 2│ /4 1N4148 ──┴── │ │ │ │/│ ──┬── │ │ │ │ │\ │ │ 10n │ │ │ └────┤ >├────■ RTS (4) (7) │ └┬┘ │ │/ │ │ │100k │ ground ■──┴───────┴─────┴───────────────────■ GND (7) (5) PTT-CIRCUIT =========== PTT ■──────────┐ │ 1k 1N4148 \│ ┌─────┐ │ /│ ├───┤ ├───┤< ├──────■ RTS (4) (7) /│ └─────┘ │ \│ └ │ BC547B ground ■──────────┘ MODULATOR ========= 100n 2k2 2k2 ││ ┌─────┐ ┌─────┐ speaker ■───┤├──┤ ├──┬──┤ ├───┬──────┐ pc (1) ││ └─────┘ │ └─────┘ │ │ 1k │ │ ┌┴┐ ──┴── ──┴── │ │ ──┬── ──┬── │ │<───■ mic input │ │ │ │ │ 100n │ 100n└┬┘ │ │ │ ground ■────────────────┴────────────┴──────┴─────■ ground pc (2) (1) connect to speaker terminal with strongest signal (2) connect to PC chassis All C's ceramic This interface is designed to be used with the Microscan version of MSCAN, and is equipped with a PTT connection. 5 1.4 Adjusting the hardware (Multiscan only) [Multi] RECALIBRATION OF THE (DE)MODULATOR IS NOT REQUIRED IF A BUILT AND TESTED UNIT HAS BEEN BOUGHT! Before using the program and matching hardware you may have to adjust a few things. For adjusting the demodulator a software- approach is used. The demodulator can be found on the Multi- scan receive board. The modulator uses a hardware adjustment by means of adjustable resistors. The modulator is placed on the transmit board of the Multiscan. The adjustments are necessary in connection with tolerances in the used parts. Calibrating the demodulator Calibration of the demodulator should only be required if you have just completed building the interface unit or you have changed any parts. If you have bought a built unit the software should already be calibrated for the interface. When calibrating the demodulator you are in fact adjusting the software to match the characteristics of the hardware (soft- ware calibration). Calibration should be done using a tone generator which has an adjustable frequency. It is however also possible with the help of another amateur station. Use the following steps for calibration: 1) Switch the program to a SSTV mode and press the spectrum menu button. 2) Apply a 1200 Hz tone to the audio input of the Multiscan. A bar will appear in the spectrum. In the top- right corner the frequency is displayed, this will have to be 1200. You do this by clicking on the lower and higher menu buttons. With these you can shift the entire spectrum downwards or upwards. The bar will now be positioned exactly under the syncindicator. 3) Apply a 2300 Hz tone. To get the frequency '2300' displayed in the spectrum use the expand and shrink buttons to expand or shrink the entire spectrum. The bar will now be positioned above the right marker (dot on the right). 4) When ready repeat the entire procedure again. Now you can write the calibration factors to the configuration file using the save button. If you do not have access to a tone generator you can also ask another amateur to transmit the tones for you, if he also uses 6 MSCAN this will be no problem since the program has a special feature for this purpose. In this case simply connect the Multiscan to the audio output of your receiver. It is also possible to calibrate the demodulator using a high- quality SSTV signal. This will however give a less exact result. The procedure for calibrating using an SSTV signal is not much different: 1) Apply the SSTV signal to the Multiscan. Use the lower and higher buttons to get a good synchronization (1200 Hz adjustment). You will now see a bar under the syncindicator. 2) Use the expand and shrink buttons to get the right greyshades in the picture. These values have to be spread all over the 1500-2300 Hz part of the spectrum (between the two markers). 3) You can now store the acquired calibration factors in the configuration file using the save button. Calibrating the modulator [TX] Calibration of the modulator should only be required if you have just completed building the interface unit or you have changed any parts. If you have bought a built unit the modulator should already be calibrated. The modulator is calibrated as follows: 1) Switch the program into the transmit mode by clicking on the RX indicator. The indicator will now show TX. 2) Enable the spectrum by clicking the spectrum menu button. The buttons 1200, 1500 and 2300 allow you to generate the tones 1200, 1500 and 2300 Hz. 3) Select the tone 1200 Hz. Measure the frequency of the signal that the modulator generates. You can do this at the output of the board. The outputlevel can be adjusted with R4 on the Multiscan transmit board. If your counter is not sensitive enough you can also measure the signal at R3. Adjust the frequency with R7 to exactly 1200 Hz. 4) Now select a tone of 2300 Hz. Adjust the measured frequency with R6 to exactly 2300 Hz. 5) Repeat the previous procedure. The modulator is now precisely calibrated. When you now select a tone of 1500 Hz you should measure this frequency at the output. A deviation of a few Hz is allowed. 7 6) Press your right mousebutton to leave the spectrum mode, and click the TX indicator twice to switch back to the receive mode. If you do not possess a frequency counter you can also simply transmit the signal and ask another amateur to measure it for you. If this amateur also uses MSCAN then this is easy: he only has to press the spectrum button and read the displayed frequency. 1.5 Computing the calibration factor Precise timing is vital for especially the new SSTV and FAX modes. A slight deviation in the crystal frequency of the PC will result in bad synchronization (picture skew) when receiving pictures. 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. Switch the program to FAX mode by clicking on the program mode indicator. 2. Select the param menu and use the +lpm and -lpm buttons to receive a picture without skew. 3. Click on the calib button and confirm by clicking calib again. 4. Repeat steps 2 and 3 until you cannot detect any skew anymore. 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, these lines must appear directly under each other. [picture] 8 2 OPERATION To start the main program type MSCAN followed by <Enter>. The program will enter the default mode which was defined during configuration. 2.1 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. Below this the 14 memories are displayed. Since FAX modes require display of high-resolution pictures, here only one big screen is visible. [picture] At the bottom of the screen you can see the console, which is made up of the spectrum, the indicators and the menu buttons. The spectrum shows the in- or outgoing audiosignal. The spectrum contains a sync-indicator. When a correct synchroni- zation is established this indicator lights up. In SSTV modes you can see three markers at the bottom of the spectrum, these 9 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 markers either mark 1500 and 2300 Hz for 800 Hz shift or 1750 and 2050 Hz for a 300 Hz shift. In the console of MSCAN you can find both (menu) buttons and indicators. Menu buttons are visible in the lower part of the console and make up the menu. Indicators can have a display function only, or can have both a display and button function. In the latter case 'pressing' an indicator will activate a corresponding function, or will select a new setting. You can 'press' a button or indicator by positioning your mousepointer above it and click your left mousebutton. Some indicators have more than one function, by repeatedly clicking on the indica- tor other functions or settings are shown. A function or setting will become active when the indicator is not changed for one second, or when another indicator is clicked. The right (and middle) mousebutton have an escape function and are used to leave a (sub)menu. 2.2 Selecting the program mode B&W SSTV -> Wraase -> New SSTV -> B&W FAX -> Col FAX To the right of the spectrum you can find the program mode indicator, which shows the current program mode (like SSTV or FAX). Clicking on it selects another program mode. 2.3 Loading and saving pictures You can load a picture from disk, from the auto directory or from one of 14 memories (which are in fact stored on disk). MSCAN will load pictures in GIF and JPEG format. Because of the high datacompression pictures will always be saved in JPEG format. Pictures can be loaded and saved at all times, even when receiving or transmitting another picture. A picture can be loaded into the entire screen or just to a part of it (called a box). In the same way the entire screen or just a part of it can be saved. MSCAN will automatically scale pictures to fit in a screen or box. In b&w modes picture colours will be translated to greyvalues. 2.3.1 Setting the path picture -> Path Here you can temporary change the path to the picture directory which you entered in the configuration menu. This 10 path is used when loading or saving a picture from/to disk. After selecting Path a cursor will be visible, you can now enter the new path, e.g. 'a:' to read a picture from disk a:. 2.3.2 Loading a picture from disk picture -> diskLoad -> screen box multi delete Depending on the mode you are in, you will be able to select screen 1 or screen 2, or only one screen. If you do not want the picture to fill the entire screen but just a portion of it, select box. Press the left mouse button to select the top left corner of the box, 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. After your selection a cursor will appear: you can now enter the name of the picture to be loaded, or press <Enter> or left mousebutton and pick a file from the directory. Use the {up} and {down} buttons to show more entries. If you want to load multiple pictures, select multi. In SSTV modes MSCAN will now load pictures to screens 1 and 2 alterna- tely. When transmitting, picture load is synchronized with picture transmission. When both screens are selected for transmission, this feature enables you to transmit several picture in a row. Pictures are loaded alphabetically, starting with the picture you selected. In FAX modes a collection of small pictures will be showed across the screen. Press the delete button if you want to delete a picture. If you have loaded a picture previously and not leaved the picture menu, the name of this picture will be showed now. You can use this name, or enter a new one, or press <Enter> or left mousebutton to pick a picture from the directory. Use the {up} and {dpwn} buttons to show more entries. 11 2.3.3 Loading a picture from the auto directory picture -> Autoload -> screen box multi delete This works exactly the same as loading a picture from disk, only the picture is not loaded from the picture directory (see configuration menu) but from the auto directory. This is the directory where pictures are stored that are received in the SSTV or FAX auto mode. 2.3.4 Loading a picture from memory picture -> memRead -> screen box Pictures which are stored in memory are in fact stored on disk in a special format. This format enables the pictures to be loaded and saved very fast and without loss of information due to compression. The procedure to load a picture from memory is almost the same as loading a picture from disk. The only difference is that you do not have to enter a name, but immediately can pick a memory from the directory. showmems In SSTV modes you can see 14 little boxes in the lower part of the screen. These boxes display the contents of all 14 memories. To (re)load these boxes with the contents of the memories press the menu button showmems. 2.3.5 Loading a standard image picture -> Image -> screen 12 A number of images are available in MSCAN. You can use these images for testing or just for a background. Depending on the mode you are in, select screen 1 or screen 2, or only screen and then pick the desired image from the directory. There is one special image called spectrum. Choosing this image will copy the current spectrum to the selected screen. You can use this to show your opposite station his spectrum. 2.3.6 Loading a picture from the Iris videodigitizer digitize -> screen box multi input One of the unique features of MSCAN is that you are able to digitize video-images just as easy as loading pictures from disk, even when receiving or transmitting a picture! To be able to do this the optional Iris videodigitizer has to be installed in your PC. The procedure to digitize a picture is almost the same as loading a picture from disk. Just select the desired screen or box and the picture will be digitized and loaded. Use input to select either the composite or the S-VHS/Hi-8 input. The multi command works the same as that when loading a picture from disk. The FAX modes have no multi command available for digitizing. 2.3.7 Saving a picture to disk picture -> diskSave -> screen box Depending on the mode you are in, you will be able to select screen 1 or screen 2, or only one screen. If you do not want to save the entire screen but just a part of it, select box. Press the left mouse button to select the top left corner of the box, then drag the box to size and press again the left mouse button. After your selection a cursor will appear: you can now enter the name of the picture to be saved. If a file with this name already exists, you will be asked if it is ok 13 to overwrite this file. Select overwr if you want to, or press again if you want to enter a different name. The picture will now be saved to disk. 2.3.8 Saving a picture to memory picture -> memWrite -> screen box The procedure to save a picture to memory is almost the same as saving a picture to disk. The only difference is that you do not have to enter a name, but immediately can pick a memory from the directory. 2.4 Text editor MSCAN has a built-in screeneditor which can be used even while receiving or transmitting a picture. Simply type a character on your keyboard and it will be placed at the position which is marked by the textcursor. You can move the cursor around with the cursor keys on the keyboard. The cursor will disappear if during 5 seconds no character has been typed. Pressing a key will make the cursor visible again. The next keys also control the position of the cursor: <Home> moves the cursor to the top-left corner of the screen <End> moves the cursor to the bottom-right corner of the screen <Ctrl>+< > moves cursor to the right of the screen <Ctrl>+< > moves cursor to the left of the screen <Backspace> moves the cursor one position to the left and erases that position <Del> clears screen and moves the cursor to the top- left corner of the screen <Tab> only for SSTV modes: moves the cursor to the other screen You can control the character's size and colour by clicking on the fontsize and -colour indicators. t s m l t s m l The fontsize indicator shows which size is selected: tiny, small, medium or large. If the indicator is blue the characters will show transparent on the screen, if the indicator is black the characters will erase the background. 14 c c c c c | | | | | | | | | | | | | | +- blue | | | +----- green | | +--------- red | +------------- black +----------------- white The fontcolour indicator shows the colour of the characters. [TX] In B&W modes coloured characters will be transmitted in their corresponding greyvalue. 2.5 Receiving and transmitting pictures MSCAN will be in RX mode after startup. Click on the program mode indicator to select the mode which you want to use to receive or transmit pictures. 2.5.1 Receiving pictures in SSTV modes Click on the mode indicator, which is to the right of the program indicator, to select the desired SSTV mode. B&W SSTV: 7.2 -> 8 -> 16 -> 32 Wraase SSTV: 24 -> 48 -> 96 New SSTV: M1 -> M2 -> S1 -> S2 Select the screen that you wish to use to display the received pictures, by clicking on the display sequence indicator. You can find this indicator to the right of the large message indicator. It has four settings: 1X -> X2 -> 12 -> XX 15 1X display pictures on screen 1 (left) X2 display pictures on screen 2 (right) 12 display pictures alternating on both screens XX pictures are not displayed, reception is off Incoming SSTV signals will now be displayed fully automatic on the selected screen(s), leaving MSCAN available for other tasks. Should manual control of reception be required, you can use the indicator to the left of the message indicator and the menu button param. The indicator has multiple functions, depending on the SSTV mode. Each function can be selected by clicking one or more times on the indicator. In B&W and New SSTV modes: top -> cls In Wraase SSTV mode: rgb -> top -> cls rgb only available in Wraase mode: kicks r-g-b sequence one colour back (causes the colour of the receiving picture to change), pressing the <Ins> key has the same effect top start reception at the top of the screen, pressing both the <Ctrl> and <Home> keys has the same effect cls does the same and also clears the screen The New SSTV mode has an extra indicator, which is positioned to the right of the mode indicator. syn -> lin Default setting is syn(chrone), which meanse the reception of a picture is started after receiving the frame startpulse (or VIS code). After that reception is fully synchronous and will continue until the next startpulse is received. In lin(e) mode every line is written after receiving a linesync pulse, just like in B&W SSTV modes. This mode is more sensitive to noise but can be useful in the next cases: 1. If the receiving signal is not crystal-controlled (like from a taperecorder) synchrone mode will not work. 2. If a startpulse is not received ok the receiving picture can be shifted to the left or the right. Selecting line mode for a second to achieve line synchronisation and then switching back to synchrone mode will position the rest of the picture ok. 16 param The param menu button's functions also depend on the selected SSTV mode. In both the B&W and Wraase SSTV modes clicking the param button toggles between manual and autosync mode. The manual mode is default. In this mode every line is written after reception of a linesync pulse, and every image is started after reception of the framesync pulse. If signals are very noisy and thus no synchronisation is achieved, selecting the autosync mode will make reception less sensitive to noise. By looking 'intelligent' to the synchronization of the SSTV signal, display of received images will improve, which is especially helpful in the Wraase colour SSTV mode to prevent coloursync hickups. This mode however only works when the transmitting stations have correct timing. In the New SSTV mode clicking the param menu button will select another menu. param -> + lpm - lpm left right RGB auto You can temporary change the linetime by clicking on the +lpm and -lpm menu buttons. Move reception to the left or to the right by clicking on the corresponding buttons. Click RGB to change the colour. The 'auto' command activates the auto mode. In this mode MSCAN automatically starts reception in both screens and saves the pictures in the auto directory afterwards, using the filename mmddhhmm (month|day|hour|minute). 2.5.2 Transmitting pictures in SSTV modes [TX] Click on the mode indicator, which is to the right of the program indicator, to select the desired SSTV mode. 17 Select the screen that you want to transmit by clicking on the tx display sequence indicator. You can find this indicator to the right of the rx display sequence indicator. It has three settings: X2 -> 12 -> 1X X2 use screen 2 (right) for transmisson 12 use both screens alternating for transmission 1X use screen 1 (left) for transmission Now click on the RX/TX indicator to start the transmission. The transmission will stop automatically at the end of the picture (indicated by the message 'auto stop'). By clicking twice on the RX/TX indicator transmission will be continuous. The picture(s) will be transmitted fully automatic, leaving MSCAN available for other tasks such as preparing the next picture or adding text to the picture. Click on the RX/TX indicator until it shows RX if you want to abort the transmission. 2.5.3 Receiving pictures in FAX modes To fully understand the operation of some functions in the FAX modes, first the terms 'scrolling' and 'endmarker' will be explained. Scrolling To be able to display long FAX pictures which can not be displayed on the standard full screen size, MSCAN uses scrolling (vertical movement) of a picture, which enables the rest of the picture to be shown. This scrolling is done mostly automatic. Only when the cursor is visible, no scrolling will take place (unless the cursor itself is moved). The endmarker The endmarker is used to mark the lower border of the current picture. 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. Click on the mode indicator, which is to the right of the program indicator, to select the desired FAX mode for reception. 18 In B&W FAX: 120 180 240 60 90 In colour FAX: 240 360 120 180 The indicator shows the number of lines per minute (LPM). Select the desired IOC by clicking on the IOC indicator, which is to the right of the mode indicator. In B&W FAX mode: 288 576 864 In colour FAX mode: 288 204 The Index Of Cooperation indicates the aspect ratio of the picture. When you select 360 LPM automatically an IOC of 204 will be set. To the right of the IOC indicator you will find the shift indicator. 800 300 This is the difference between the frequency for black and the frequency for white video. [TX] When transmitting a shift of 800 Hz is automatically set. In b&w FAX mode you will find the next indicator to the right of the shift indicator. top -> cls 19 In colour FAX mode it has one extra setting: rgb -> top -> cls rgb only available in colour mode: kicks r-g-b sequence one colour back (causes the colour of the receiving picture to change), pressing the <Ins> key has the same effect top start reception at the top of the screen, pressing both the <Ctrl> and <Home> keys has the same effect cls does the same and also clears the screen Use the rx display sequence indicator to switch on and off reception. 1 X 1 = screen 1 (= reception on) X = no screen (= reception off) Various parameters in the FAX mode can be changed by clicking the param menu button. param -> + lpm - lpm left right Video Calib Auto You can temporary change the linetime by clicking on the +lpm and -lpm buttons. Move reception to the left or to the right by clicking on the corresponding buttons. Click the video menu button to do some realtime image processing. 20 Video -> Invert Mirror invert invert the incoming videosignal (black becomes white and white becomes black) mirror the incoming videosignal will be written to screen in the opposite direction You probably will only use these commands for shortwave reception of commercial (weather)stations in B&W FAX modes. Auto For automatic reception of FAX pictures click the auto menu button. This will activate the FAX auto mode. MSCAN will now wait for a starttone. Once detected it will determine the transmissions IOC and mode (b&w or colour). After that it will wait for the synchronization signal and use it to determine the LPM and shift and synchronize reception. It will then wait for the start of the picture and begin reception. When the stopttone is detected the picture will be saved to the auto directory and MSCAN will wait for a next transmission. Pictures will be saved with the following name: mmddhhmm (month/day/hour/minute). The auto mode can be aborted by pressing <Esc> or right mouse button. 2.5.4 Transmitting pictures in FAX modes After loading or digitizing a picture notice that the endmar- ker will be automatically placed at the lower border of the picture. If you want to transmit more or less of this picture, you can change the position of the endmarker by clicking the endmarker indicator: -- Now position your mouse at the desired position and click again, the endmarker will move to this new position. Optional- ly select the desired LPM and IOC and press the RX/TX indica- tor to start the transmission. To abort the transmission click the RX/TX indicator until it shows 'RX'. 21 2.6 Processing pictures with the toolkit Press the toolkit menu button to activate all image processing functions. toolkit -> mirror colour aspect move draw debug Click mirror to swap left and right sides of a screen. Click colour (only in colour modes) to change the colours of a picture on screen (colours will be 'rotated'). Click aspect to correct a picture which is received in the wrong IOC. Click move to redefine the top-left corner of a picture. This will be useful in FAX modes if a picture has been received with bad synchronization. Click draw to draw white pixels on the screen using your left mousebutton. The debug menu button will only be shown in B&W SSTV mode. It is meant for technical support only. 2.7 Managing the spectrum [Multi] The spectrum occupies the left part of the console and shows the frequency spectrum of the received or transmitted signal. In SSTV modes it also features a sync-indicator which is the little square box above the 1200 Hz marker. Whenever MSCAN is correctly synchronized to an SSTV station a white dot will appear in this box. By pressing the spectrum menu button the following submenu will be presented. 22 spectrum -> shrink expand lower higher default load save This menu is used when calibrating the Multiscan interface. It can also be used to (temporary) change the spectrum calibra- tion, e.g. to compensate for a station which has a frequency deviation in sync- and or videotones. The reception spectrum can be shifted using the lower and higher menu buttons. Pressing the lower button decreases all frequencies (darker video) and pressing the higher button increases all frequencies (brighter video). You can also shrink (less contrast) or expand (more contrast) the spec- trum, this will leave the 1200 Hz frequency unchanged. Other commands are: d)efault: loads the default calibration l)load: loads the last stored calibration s)ave: saves current calibration to disk. [TX] In transmit mode the spectrum menu button shows the following submenu. spectrum -> 1200Hz 1500Hz 2300Hz APT 23 Pressing a button causes MSCAN to transmit the corresponding tone for 5 seconds. Pressing APT shows: APT -> 200Hz 300Hz 450Hz 675Hz Pressing a button causes MSCAN to transmit the corresponding starttone, which are used in FAX modes. 24 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 unfortunately 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 As you can see both IOCs have the same starttone of 200 Hz. Because the auto mode of MSCAN uses the starttone to determine the IOC, it will always select an IOC of 288, except for the 360 LPM mode which is mostly used with an IOC of 204. B Troubleshooting Because MSCAN is a complex multitasking 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) 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 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 25 incompatible mouse is causing the problem? Is your adapter capable of displaying 16.8 million colours (truecolour) with a resolution of 640*480? 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 MSCAN to perform satisfactory then contact your supplier who will try to help solve your problem. 26 APPENDIX II - MODE DESCRIPTIONS MSCAN 2.0 supports a number of modes. The outline specification for these modes 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). [picture] 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 27 syncpulse, the receiver cannot be mistaking about the correct colour sequence. [picture] 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 an 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. 28 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 recogni- sed 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). Enjoy MSCAN! Mike Versteeg PA3GPY CombiTech 29