        ͻ
                         M I C R O S C A N   1 . 3                  
                                                                    
              The shareware SSTV & FAX program for the IBM-PC       
                                                                    
                        (c) Copyright 1994 CombiTech                
             Morelstraat 60, 3235 EL Rockanje, The Netherlands      
          This program may be copied in its original integral form  
        ͼ


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 Hjrring, 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 <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. 

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 <F7> 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 <alt> 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 <Enter>. 

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 <Alt> 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 <alt> 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 <Esc> 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 <Enter> (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 <Enter> if this is the file 
to be erased, or enter a new filename or press <Enter> 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 <F7>. After this activate the multi 
mode and enter the filename from which to start loading, or press <Enter> 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. <F7> selects the screens for the current 
mode, <alt-F7> for the other mode. 

Example: when receiving, the command <F7> <1> causes received pictures to be 
displayed in the left screen. By pressing <alt-F7> <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 <F9> 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

