Universal M-400 User manual

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Universal Radio, Inc.
6830 Ame[icana Pkwy.
Reynoldsburg, Ohio 4306 '
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UNIVERSAL M-400
Version 2
Owner's Manual
By
Digital Electronic Systems, Inc.
&
Universal Radio Research

FIRST EDITION
FIR8T PRINTING
V1.0 03/01/94
Copyright ©1994
Universal Radio Research
6830 Americana Pkwy.
Reynoldsburg, Ohio
Reproduction or publication of the contents in any manner
without the written permission of thepublisherisprohibited. No
liabilityisassumedwithrespectrotne use ofinformation herein.
Printed in the United States of America
iSfjN 1-S8212j-j9-S

TABLE OF CONTENTS
1.0 Introduction 1
2.0 Installation 1
Power Connection 1
Receiver Connection 2
Printer Connection 2
3.0 Functional Modes 3
4.0 Operating Mode Select 4
5.0 Indicators •...................•........................................................ 5
6.0 Display Methods 6
7.0 Baudot 8
8.0 ASCII 12
9.0 AUTOR (SITOR A &B) 13
10.0 FEC-A 14
11.0 SWED-ARQ 15
12.0 FAX 16
13.0 ACARS ................................................
•••.••.• •••..••• •.......•..••••18
14.0 Pager Modes 20
15.0 POCSAG 21
16.0 Super POCSAG 22
17.0 GOLAY 23
18.0 CTCSS (PL) 24
19.0 DCS 26
20.0 DTMF 28
21.0
Programming .......••.•.......................• ••.• •••......•.•••••••...•...••••• 29
Default Mode 30
Default Serail 30
Mute Timer 31
Memories - Generic ; 32
Memories - CTCSS 33
Memories - DCS 34
Memories - DTMF 35
Printer Port 35
22.0 Auxiliary Controls 36
23.0 Miscellaneous Notes 37
Appendix A
Appendix B
AppendixC
AppendixD
Appendix E
AppendixF
Appendix G
Appendix H
Appendix I
AppendixJ
DTMF Frequencies 38
Standard CTCSS Codes 38
Standard DCS Codes 38
Additional References 39
Specifications 40
Pager Tuning Level Setting 41
Receiver Conversion for Accurate PL &DCS 42
Semi-Conductor List 43
Limited Warranty 43
Schematic 44

1. INTRODUCTION You are
now the owner of the Universal M-400v2 Decoder. The M-400v2
features new modes and capabilities never affered in a "reader" befare.
Shortwave reception
modes include:
•Baudot
•ASCII
•
SITaR A & B
•FEC-A
•
SWED-ARQ
• FAX (ta printer port)
45, 50, 57, 75 and
100 baud.
75, 110 and
150 baud.
automatically selected by
AUTOR.
96 and 144 baud.
S,
Mand Llengths.
120 LPM 576 IOC
For the
VHF-UHF enthusiasts, the following capabilities are featured:
•
ACARS
·POCSAG
• GOLAY
• CTCSS (PL) Decoding
• DCS (DPL) Decoding
•
DTMF Decoding
Aviation
message/telemetry mode.
Digital
pager mode .
Digital
pager mode .
41 standard frequencies
104 standard codes
16 digits.
2. INSTALLATION
Reminder ..•
Before operating,
plug the powercord
into the M-400 ,
thenplugthepower
adapterintothewall.
This manual will start with installation and general features. Then shortwave
modes will be discussed. Next "scanner" modes and features will be
reviewed.Finally specialized
programming will be examined. Acareful
review of this manual is required to understand and operate this device.
UNIVERSAL
UP SENSE
MK
G"'IN 0M·400 DECODER 0
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Oniversal
M-4tOO
•
DOWN FUNCTlON INPUT
Version 2.00
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ElI 1l $
+ Important Note: Listenersare remindedthat the unauthorizedinterception
and/or divulgence of private, non-broadcast, commun ications may violate
federal and/or state laws.
The M-400 should be located in a convenient location close to your radio
receiver and / or scanner. Do not place the unit on top of, or
close to sourees
of heat such as radiators, heat ducts, etc. The Liquid Crystal Display (LCD)
screen on the
M-400 provides the best contrast and clearest display when
viewed perpendicularto the sloped front panel or from a level below this line.
Do not locate the
M-400 where it may be exposed to water or excessive
moisture.
IAI• POWER CONNECTION
... WARNING! Please read betare plugging unit into the wall ...
First, insertthe coaxial plug of the wall-mounted power adapter into the hole
of the rear panel of the
M·400 marked "11-14 VDC ". Then, plug the power
adapter into the 110 volt AC wal! outlet. Please do this to avoid electrical
shock and/or damage to the M-400 . Do NOT insert or remove the power
connector while the AC power adapter is plugged into the wal!. Do not use
extension
cords or any other type of extenders or adapters.
Un iversal M ·400 De coder
Page 1
Owner 's Manual

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DEVICE, PURSUANT re SUBPAR TJ. PAFlr I ! OF
Fe e RULES AS Q F0 4TEOF'MANUFACTURE
I I
I I
Conneet Conneet'
parallelprinter supplied
here if power supply
desired. here.
DISC SPKR
IN IN
I I
Inputtor I
lowlevel I
audio. I
Inputtor
highlevel
audio.
SPKR
OUT
9
I
I
Conneet
extemal
speaker
here if
desired.
PRINTER 11·14 VDC
Reminder ...
If a plugis inserted
into the DISC IN,
then the SPKR IN
willbedisabled.
Note .•.
For more informa-
tion on connecting
theM-400toa scan-
tner, please see
AppendicesF&G.
IAIWarning ...
Theprintermustbe
turned OFF when
power is applied to
theUn iversal M-400 .
•RECEIVER CONNECTION
The receiver audio output may be connected to the M-400 by one of two
methods, depending upon the type of audio output being used.
1. Speaker Audio
Plug one end of a suitable audio patch cord into the speaker output of your
receiver and the other end into the rear panel jack of the M-400 marked
"SPKR IN". With most receivers, making the conneetion to the speaker
output will switch off the receiver's internal speaker. The M·400 accommo-
dates this by providing an output to drive an external speaker. Refer to your
receiver's instruction manual for information on selecting an external speak-
er. Follow the receiver manufacturer's recommendations - the speakerthat
you connect to the M-400 will actually be driven directly by your receiver's
output. Gonnect the external speaker to the rear panel jack of the M-400
labeled "SPKR OUT".
2. Low-Level Audio
Gonnect the low-Ievel audio output (discriminator, detector, or recorder
output) of your receiverto the M-400 rear panel connectormarked "DISG IN".
Conneetiens to the low-Ievel receiver outputs do not normally affect the
speaker output of most receivers. If the low-Ievel audio input is used the
"SPKR IN" and "SPKR OUT" jacks may still be used to switch aremote
speaker with the M-400. The "SPKR" jacks are disconnected trom the
internal demodulatorcircuits when a plug is inserted into the "DISG IN" jack.
Therefore you cannot use the SPKR IN and DISG IN at the same time.
Note: Some receiverswill notprovide enough volume from theirrecord output
jacks. In such a case, you may have to use the receivers speaker output.
• PRINTER CONNECTION
You may connect aGentronicsparallel interface compatible printerto the M-
400 using a standard "PC" printercabIe. Gonnect the 25 pin "D" end of the
cable to the M-400 "PRINTER"jack and the 36 pin end to the printer. Always
turn the M-400 on first ... then power-up the printer. Use of the printer is
optional foroperation ofthe M-400inall modes except FAX. The M-400 FAX
output is available only at the printeroutput. For properoperation in the FAX
mode, the printer must be compatible with the Epson 8 pin or 24 pin bit-
mapped graphics modes. Universal Radio maintains a list of known-
compatible printers. Please check this source prior to investing in a printer
which may not suit your needs.
Un iversal M -4OQ Decoder Page 2
Owner's Manual
- - - _ .. ._ -- --- ---- -'-- -------

3. FUNCTIONAL MODES We are now ready to turn the M-400 on. To do this turn the GAIN contral
clockwise. The display will briefly show:
Universa1 M-400
Version 2.00
Reminder:
When correspond-
ing with the factory
or
your dealer,
please specify your
version number.
The display next display the "default mode" (to be explained later) and then
will go blank. The M-400 is now ready to operate. (You must wait tor the
display to clear before starting).
Pressing the FUNCTION button steps the display through the following
functional modes:
Mode Typical M-400 Display
•Operating Mode Se/eet
BAUDOT
NOR
75
170
•Programming Aeeess
Press "SENSE" for
Program Mode Menu
•AuxiliaryContro/s 1
Speaker MAN
Scro11 Rate
OFF
5.0 S
OFF U.O.S.
__ I
•Auxi/iary Contro/s 2
• Text Reeeive
1blank, or recently received text.
We are initially going to be concerned with the Operating Mode Se/eet and
Text Reeeive modes. These modes are most closely associated with the
reception of shortwave RTTY and FAX.
Notes:
•WhenevertheM-400is operating, and the displaywould otherwisebe blank,
ablinking asterisk (*) wil! appear in the upper right hand corner of the LCD
display.
• As mentioned on the previous page ... If you are using a printer, be sure to
turn the M-400 on first, then turn the printer on.
• When brawsing through these alternate display modes, reception in the
currently selected mode will continue. Output to the printer will not be
interrupted and received data (string or burst formats) will be held in queue
until the unit is returned to the Text Reeeive mode. If a new operating mode
is selected, the new mode does not take effect until the unit is switched fram
the Operating Mode Se/eetto Text Reeeive operation.
Universal M-400 Decoder
Page 3
Owner's Manual

4. OPERATING MODE
SELECT After the M-400 isturned on, and the screen has cleared, you may then press
the FUNCTION key to see the currently selected reception mode. Pressing
the UP and DOWN buttons wil! step through the other reception modes:
BAUDOT, ASCII, AUTOR , FEC-A, SWED-ARQ, CTCSS, DCS,
DTMF, POCSAG, Super POCSAG, GOLAY, ACARS, FAX
•SELECTING A RECEPTION MODE
Simply continue to press the UP or DOWN key until the desired mode
appears.
•SELECTING NORMAL IREVERSE
!! the indicated mode requires manual setting of the demodulator sense
(normal or reverse) then either NOR or REV wil! appear on the screen below
the mode. For example,the BAUDOTmode may be set for normal or reverse,
therefore the display could show:
IBAUDOT
. NOR
Pressing the SENSE button wil! toggle between NORmal and REVerse
demodulatorsense lfthe sensefunction isapplicableto the currentlyselected
mode. (If the displayed mode is SWED-ARQ then the SENSE button wil!
select Short, Medium or Long character groups).
Itisnotabsolutely necessaryto set the proper sense at this point. The SENSE
button operates exactly as described above when the M-400 is in the TEXT
RECEIVE mode, except there is no on-screen indication of the selected
setting to referto. Inotherwords,you can change the sense, "on the t1y" while
you are receiving the signa!.
/f no button, other than FUNCTION is pressed, then the next press of the
FUNCTION button wil! advance to the PROGRAMMING ACCESS display
screen. If any button, other than FUNCTION is pressed prior to pressing the
FUNCTION button, then a different sequence of events will occur as de-
scribed below. In any event, if anotherkey is pressed priortoFUNCTION, the
unit wil!return tothe Text Receive mode at the end ofthe MODE SELECTION
sequence.
The mode of operation which isdisplayedonthe screen when the FUNCTION
button is pressed wil! be the new operating mode. If there are no user-
selectable parameters associated with the new mode (other than received
sense) operation will immediately begin in the new operating mode.
These 'fixed-parameter' modes include:
AUTOR,CTCSS ,DCS,DTMF,POCSAG,
Super POCSAG, GOLAY, ACARS and FAX
Ifthe new mode of operation is notone of these 'fixed' modes,the screen wil!
display the current demodulatorshiftvalue. Pressing eitherthe UP orDOWN
buttons wil! step through the fixed shifts of:
170, 425 and 850
Un i versa l M·400 Decod er
Page 4
Owne(s Manua l

5. INDICATORS
Variabie (Le.non-standard) shiftscan also be selected inthe range of 100 to
1000 Hz. Ta do this press either UP or DOWN buttons while holding down
the SENSE button. This wil! vary the shift in 5 Hz steps (at a rate of 4 steps
per second) as long as bath buttons are pressed.
NOTE: Press and hold the SENSE button befare pressing either UP or
DOWN and do not release the SENSE button until after releasing UP and
DOWN buttons.
Observing the MK and SP LEDs wil! assist in setting the unit to the proper
shift. The goal is to get the MK (mark) and SP (space) LEDs to flash with
equal brightness. When the desired shift has been selected, press the
FUNCTION button again.
If the selected mode is SWED-ARQ, then operation wil! commence in the
new mode. If the selected mode is BAUDOT, ASCII or FEC-A, the screen
will display the default (or current) speed setting. Pressing the UP and
DOWN buttons will step through the available standard speeds of the
selected mode. When the desired speed is indicated on the screen, press
the FUNCTION button again and operation at the newly selected mode will
begin.
Nots:
Ifyou haveyour printer on-Iine during mode selection, the printer will pertorm
a line feed when the FUNCTION button is pressed to select a new mode.
This is normal.
The M-400 has four light emitting diodes (LED's). Their functions are:
MK Indicates reception of a marktone (1275 Hz).
SP Indicates reception of a space tone.
INPUT Indicates adequate level of audio is present at the input and the
GAIN control is set high enough.
DATA Indicates the unit is receiving data from the demodulator section.
In Baudot
RTIY this merely indicates the transition from Mark to
Space. In FEC-A this indicates received data or idle.
Universal M·400 Decoder
Page 5
Owner's Manual

6. DISPLAY METHODS The LCD (LiquidCrystal Display) on the M-400front panel iscomposedoftwo
lines oftwenty characterseach using a5x7 dot matrix for each character. This
display is used to assist in setting the mode and other operating parameters
and functions. Under normal operation, the display serves to show the
received text or other decoded information.
In this display function, there are four distinct formats used to present the
received information depending upon the current operating mode: String,
Burst, Direct and None. The M·400 automatically selects the appropriate
display method! The following explanation of each display method is
provided for those desiring adeeperunderstanding of how the M-400works.
• String Display Method
The string format is used to display text in modes where the data is received
at a relatively constant rate which is slow enough that it can be read and
understood in"real time" conditionsby the average individual. Charactersare
displayed,from leftto right,onthe lower LCD !ine. When the lower !ine isfilled,
its contents are moved to the top line (over-writing any text which was on the
top line) and the bottom !ine is c1earedto make ready for the next !ineof text.
This is commonly referred to as "scrolling". Any partial words which were not
completed at the end of the !ine when the display is scrolled are transferred
to the beginning of the new line. This prevents the break-up or hyphenation
of displayed words.
If sorne of the received text is missed or needs to be reviewed, the UP and
DOWN buttons may be used to serail baek through previously reeeived text.
This is described in detail on the next page under "Manual Text Scrolling".
String display mode is used for: BAUDOT, ASCII, AUTOR (SITOR AlB),
FEC-A, SWED and DTMF.
• Burst Display Method
The burst format is used to display text in modes where the reeeived data
oceurs at very high instantaneous rates but only for relatively short durations
at any given time. If these types of modes were displayed in "real time" as in
the string mode, the user would be able to read only the last two lines of each
'burst'ofdata; the rest of the burst would scroll past the displayinablur. Since
the average data rate ofthese burst modes isusuallywithin the readingspeed
of the average person, the burst format simply spreads the received bursts
over a longer period of time.
The burst format separates the received text into individual !ines and then
scrolIs one line onto the display at a time. The rate at which the new lines are
presented is controlled by the user by specifying the minimum time interval
between suceessive new lines. The procedures for doing this will be
described in detail later on. The scrolling rate should be selected to be slow
enough for comfortabie reading, but no sa slow as to allow the averaging
buffer to become full. The M-400 will retain up to 8,000 reeeived text
characters in its buffer.
Ifsome of the received text or data is missed or needs to be reviewed. use the
UP and DOWN buttons to scroll back through previously received text. This
is described in greater detail at the end of this seetion.
Burst displaymode used for: POCSAG, SuperPOCSAG, GOLAY&ACARS.
Un iversal M·400 Decoder
Page 6
Owner's Manual

Reminder:
After scrolling, you
mustpress UP and
DOWN simulta-
neously to resume
displayingincoming
text.
•Direct
Display Method
The direct format is used to display the results of non-text decoded informa-
tion. This format is used only when operaling in the CTCSS and DCS sub-
audible signaling modes. The left side of the top LCD line is used to display
the 3 or 4 digit value of the received signa!. When these signals are keyed,
the same pattern is repeated over and over until the transmission stops. For
this reason, the M-400 simply displays the decoded value as long as it is
present. When the signal stops, or becomes too weak ordistorted to properly
decode. the LCD display segment is blanked.
The M-400 has the capability of comparing the decoded CTCSS or DCS
pattern with user-programmed values and turning on the speaker output
during the time when a match exists. This feature will be describedin greater
detail later.
Direct display mode is used for: CTCSS and DCS
•
"None" Display Method
While the M-400 is operating in the FAX mode, the LCD display will simply
show the word FACSIMILE. As the name 'none' implies, no received
information is presented on the display. The FAX image is strictly routed to
the parallel printer port.
I FACSIMILE
MANUAL TEXT SCROLLING
Text (orother information)which is received and displayed ineither the String
or Burstdisplay formats isstored inthe 4,000 charactertextbuffer. Witheither
of these formats, as new information is received and displayed, the oldest
displayed text is seraIled off the top line of the LCD and disappears.
This 'lost' information may be retrieved for review with the use of the UP and
DOWN buttons. Each press of one of these buttons wil! cause the display to
scroll up or down, one line at a time through the data stored in the text buffer.
Pressing DOWN repeatedly wil!bring you to the topof the text buffer. To help
visualize this, think of the buffer as a sheet of paper and the LCD as a fixed
window. The paper gets moved up or down behind the fixed window.
When either UP or DOWN button is first pressed, the automatic display
operation will be suspended. In
order to restore normal operatIon of the
display, press and release both UP and DOWN buttons simultaneously. The
LCD screen will be cleared and normal text display wil! then resume. This
procedure does not
f1ush (erase) the stored text. It just moves the LCD
"window" down beyond the last line. This is a very important paragraph to
understand.
Universal M·400 Decoder Page 7
Owner's Manual

7. BAUDOT In Chapter4we spoke generally about selecting a mode, and then selecting
the speed, sense and shift. Now we are going to review this procedure as it
applies to specific modes.
We are going to start witn the oldest teletype mode, Baudot. Many Baudot
stationshave recently changedto newermore reliable modes such as SITOR
and FEC-A. However, there remains anumberof weatherand press stations
using this mode. There isalso a large population ofencrypted Baudotstations
which cannot be decoded. It is therefore advisable to seek known Baudot
stations as listed in various books, newsletters and directories. This will
dramaticallyimproveyourchances ofobtainingareadable signa!. Especially
as a beginner, you should practice on a streng reliable station such as CFH
Weather (see sample Baudot station list on next page).
To select the Baudot mode, press the FUNCTION button. The currently
selected mode ofoperationshould appearat the upperleft of the LCD screen.
Use the UP orDOWN buttons to step through the various operating modes
until the screen displays:
I
BAUDOT
. NOR
Press the FUNCTION button. The screen will now display: .
I
BAUDOT
. NOR 170
The 170 indicates that the demodulator is set for a shift of 170 Hz. Use the
UPand DOWN buttonstoselectthe proper shiftforthe received signa!. When
correctly tuned, the MK and SP will flash with equal brilliance. This will show
you are physically tuned to the tones of the signal (mark and space). It does
not indicate whether your have the correct mode, speed, or sense selected!
Press the FUNCTION button. The screen will now display:
75
170
_~l
I BAUDOT
NOR
The 75 indicatesthat the unit is set to decode aBaudot signalof 75 baud. Use
the UPand DOWN buttonsto selectthe properbaud rate (speed)
forthe signal
to be received. Available speeds are 45, 50, 57, 75 and 100 baud.
Press the FUNCTION button. The M-400 is now in the Text Receive mode
for Baudot. You
may be properly receiving text at this time. If not you can
press the SENSE button. This will toggle you from NORmal to REVerse (or
visa versa). There will be no specific indication of this as such (other than
possibly the result of this action ... which
may be readable text).
The following is a brief tutorial on radioteletype for beginners ...
RTTY, which stands for Radio TeleTYpe, isaterm used to coverawide variety
of radio communications codes. What they all have in common is that they
are based on teletype operation. Tele (far away, or remote) type (typing, or
printing) originally used wires to conneet the teletyping machines together.
Universal M-400 Decoder
Page 8
Owner's Manual

This on and off keying is called abinary, ortwo state code . On shortwave the
two states (on and oft) are represented by two distincttones, or frequencies,
calied the Markand the Space.This
separat ion betweenthe mark and space
frequencies is referredto as the shift. Common shiftsinclude 170, 425 and 850
Hz. It is the responsibility of the shortwave receiver to convert these radio
frequencysignalsdownto audiotones.
Any instability or driftin the short-wave
receiverwill degradeof performanceof the
M-400 . The receivermustalso be
capable of providing acomplete
signal to be demodulated . While narrow
filters may be desirabie in certain cases, in other instances they can prevent
both needed portions of the signa'
(Mark and Space), from reaching the M-
400.
For 170 Hz shift use at leasta 500 Hz filter, for 425 Hz use at leasta 1000
Hz filter, and for 850 Hz use at least a 2000 Hz (2 kHz) filter.
The objective in tuning a
RTIY signal is to match the mark and space tones
coming from the receiver to the same frequencies as the Mark and Space
filters in the M-400 's demodulator . In order to match thesetones, the receiver
must be capable of tuning in very fine increments. If the main tuning of the
receiveris not capableof varyingthe frequencyby
10Hz. or less, then the RIT,
BFO or similar fine-tuning control must be used to tune RTTY signais.
We strongly suggest you initially try for published
RTTY stations on known
frequencies, transmitting with known baud rates and shifts. Randomly tuning
around,trying different,
modes and speeds will be unproductive. To tune a
typical Baudot RTTY signal you would:
1. Set the M-400 for the correct
baud rate (usually 50 or 75 baud).
2. Set the M-400 for the correct shift (usually
170 Hz. in the ham
bands , 425 or 850 Hz. outside the ham bands).
3. Slowly tune the rece
iver around the signal until bath the Mark
(MK) and Space (SP)
LEDs flash with equal brightness.
4. If readable copy
does not follow, then press the SENSE button
to change the sense (or polarity) of the signa!.
A few general reminders ...
• If you can't get both the MK &SP to light, try a different shift.
• If you still can't both MK &SP
check your filter selection on the receiver.
• You must always try both senses (NOR and REV).
• In order to get readable Baudot
RTTY you must have all of the
tollowing correct:
•Speed, •Sense and • Shift (some
copy is possible with wrong shift).
•
The station must be active (not idling) to copy.
•There are
many 75 baud Baudot signals on shortwave that are encrypted
in content.
The apparent "garbage" you are getting is what is being sent.
•
Many RTTY trequencies are seasonal in nature.
•
Many RTTY stations only transmit on an as-needed basis.
•
Many RTIY stations transmit in a directional pattern and therefore
may not be audible in your area .
•Propagation may not permit reception at a given time.
•
Some stations only transmit on certain days or with reduced weekend
schedules.
•Learn the easier
RTIY modes like Baudot and SITaR, before exploring
the more advanced modes.
•
When looking tor aspecific RTTY station always try the Iisted trequency
plus or minus 3 kHz.
Un i versal M-400 Dec ode r
Page 9O
wner's Manual

UNSHIFT ON SPACE FEATURE
The Unshift On Space (UOS) capability is a fairly subtIe feature that only
applies to the Baudot-based modes (Baudot, SITaR AlB, FEC-A and
SWED-ARQ). You do not need to fully understand this feature to monitor
these modes.
Baudot is a live data bit per character code, providing 32 possible bit
combinations. This does not provide enough unique characters for the 26
letters, 10 digits, and punctuation used in the English language, so Baudot
uses two sets of letters, or cases. One case (letters or LTRS) contains the
letters of the alphabet, while the other case (figures or FIGS) holds the
numbers and punctuation. Normally, the contral codes to select a case are
only sent when there is actually achange in the case of the transmitted text,
or, in some services, at the end of every line. Normal text contains mostly
lower case characters. 11 an errar occurs in the reception of a character,
there is a chance that the resulting error will cause an improper shift into the
upper case. If this occurs, the upper case representation (Le. incorrect
representation!) of all the following text will be displayed (numbers, punctua-
tion, bells, etc.), until the sending station again sends the lower case (LTRS)
control code.
Ifthe M-400's UOS feature is left on itwill quickly correct this condition. UOS
will force the M-400 into the lower (LTRS) case each time the space
character is received. At the end of every word, then, the lower case
operation is restored, and the most that would be lost to gibberish in the event
of a false FIGS shift, is one word.
The M-400 provides this lunction on a user-selected basis. Please reler to
page 36 to program this feature on or oft. Why would we want to turn off such
amarvelous invention? Certain stations,particularlyweathertransmissions,
send columns of numbers. With the UOS on, each time a space is received
to place the numbers (FIGS) in column form the unit will switch to LTRS and
you will see a column of numbers followed by several columns of letters that
make no sense at all.
As an example; the date of MARCH 12, 1 9 8 7 would appear as MARCH
12 , QO IU if the UOS were enabled.
Most users prefer to leave the U.O.S. "on" except during the reception of
RTTY weathertransmissions. This way when the Baudot code inadvertently
falls into the wrong case it is quickly restored to the proper case.
Uni versal M-400 Dec oder
Page 10
Owne~s Manual

iBAUDOT SAMPLE FREQUENCIES
TIME (GMT) kHz. Baud
Shift Station
0000
6848 50
425 PAP press alse
11497
0030
7806 50 400 TANJUG English press
0100
11065 75
475 XINHUA English
press
0114
7996 50 400
TANJUG English press
0300
4004 50 425
TELAM press alse 7428
0400-0415 11«78 50
425 KCNA English press
0500
16135
75 425 APN press
0600
17468 50
425 MTI English press
0700 9830
50 425
SPK English press
0801
9133 50 425
ATA English press
0945
14568 50
425
KCNA press alse 10580
1000
15632 50
230
KCNA English press
1120
13440 50
425 TANJUG press
1120
17470 75 425
XINHUA English press
1220
18039 50
850
AA press alse 19040
1300
13371
50 425
INA English press
1330
13113
75 365
XINHUA English press
1340
14800 50
600
TAP French Press
1400
18220 50
425
MAP English press
1400
18055
75 425
MFA/TANJUG Press
1400
14373
50
425
INA English press
1400
13648
50 425
CTK English press
1400
7695 50
850
CNA press alse 9090
1400
5097 50
425
JIJI press also 8175
1430
16117
50
425
PANA English press
1500
5195 50
425
ADN press
1500-
9430
50
425
ATA English press
1500
7800 50
425
IRNA English press
1500
9395
50
425
KCNA press also 10580
1500
9331 50
425
VNA press alse 10599
1500
19980
50
600
IRNA English press
1500
24102
75 400
TANJUG English press
1520
21860
75
425
TANJUG English press
1530
14910
75 400
TANJUG English press
1540
14764
75 350
GNA Eng1ish press
120011500
20085 50
425
ANSA English press
1600
20560
50
425
JANA English press
1630
19087
50
425
CLP Spanish press
1800
8020
50
425
KCNA press
1900
13440
50
425
TANJUG English press
1900
14928
50
425
PL Press
2100
11430 50
250
KCNA French
press
6496
75
850
CFH
Weather
(alse
FAX)
10535
75
850
CFH
weather
(alse
FAX)
13510
75
850
CFH
Weather
(also
FAX)
14356 50
425
GFL24 Weather
18230
50
425
GFL25 Weather
Universal M·400 Decoder
Page 11
Owner's Manual

8. ASCII ASCII stands for American StandardCode for /nformation /nterchange. The
ASCII code is similar to the Baudot code except itscharacter iscomposed of
7 data bits instead of 5. ASCII is not apopular radio mode.
To select the ASCII mode, press the FUNCTION button. The currently
selected modeof operation should appear atthe upper left ofthe LCD screen.
Use the UP or DOWN buttons to step through the various operating modes
until the screen displays:
I ASCII
NOR
Note: The screen
may indicate REV
rather than NOR.
110
170
Reminder:
ASCII signals are
currently very
scarce on short-
wave (HF).
Press the FUNCTION button. The screen will now display:
I
ASCII
. NOR 170
The 170 indicates that the demodulator is set for a shift of 170 Hz. Use the
UP and DOWN buttons to select the proper shift for the received signal (refer
to the section on DEMODULATOR TUNING). When the signal is correctly
tuned, but not decoding; try changing the sense from NOR to REV.
Press the FUNCTION button. The screen will now display:
I
ASCII
. NOR
The 110 indicates that the unit is set to decode an ASCII signalof 110 baud.
Usethe UP and DOWN buttons to select the proper baud rate (speed) for the
signal to be received. Available speed are
75,110 and 150 baud.
Press the FUNCTION button. The M-400 is now in the Text Receive mode
for ASCII. As always, tune the radio to get both the
MK and SP LEDs to blink.
ASCII is not generally used on the HF bands except by W1AW, a few
amateurs, and then usually at 110 Baud. W1AWis the master station of the
American Radio Re/ay League located in Newington, CT. They transmit
bulletins daily for radio amateurs in Baudot 45, ASCII 110 and SITOR. Their
schedule (in UTC) is:
DAILY
0100,0400,2200
MON-FRI
1500
Universal M-400 Decoder
3625, 7095, 14095, 21095 &28095 kHz
Page 12
Owner's Manual

9. AUTOR (SITOR A &B) The SimplexTelex OverRadio (SITOR) code is used extensively in maritime
and diplomatie communications. SITOR A and
Bare popular shortwave
modes. The SITOR signalsare always sent at 100 baud and usually 170 Hz.
shift. SITOR A is one of the easiest RTTY modes to find and tune. lt is easy
to find because of the unique chirp, chirp, chirp sound of two stations
interchanging data.
Using the frequency chart below, listen for the distinctive chirp, chirp sound.
Once again, the idea will be to tune the radio receiver in such a manneras to
get both the MK and SP LEDsto flicker on the M-400. Now that you have bath
Mark and Space you
mayor may not be getting text on your screen. When
you tune to a SITOR A station,the chirpsyou hearmay be the three character
groups being sent, or they may be nothing more than the acknowledgment
pulsesfrom the receiving station (orin "computer"terms ...you may be merely
Iistening to the "handshaking"). The sound is quite similar.However, in time
you will be able to teil the difference by "ear". Until then, be patient.
Understand that when the receiving station is done receiving he will probably
start transmitting text back to the original transmitting station;
DAYS
12465 - 13070 kHz.
16860• 17225 kHz.
22315·22555 kHz.
EVENINGS
6325 - 6490 kHz.
8435 - 8700 kHz.
12465 -13070 kHz.
To select the SITOR A mode set the M-400to the "AUTOR" mode. To do this
press the FUNCTION button. The currently selected mode of operation
should appear at the upper left of the LCD screen. Use thelUP or DOWN
buttonsto step through the various operating modesuntil AUTOR appears on
the screen. Press the FUNCTION button. The unit is now operating in the
AUTOR mode. As always, tune the radio to get both the
M~ and SP LEDs
to blink with equal brilliance. Enough audio level must be avallableto light the
INPUTLED to full brilliance (otherwise the MKand SPLEDs !may not light).
SITOR Bconsists of a continuous data stream of 100
~aud data bits
characterized by its "singing" sound. It does not have the dlsfinctive "chirp-
chirp" sound of mode A, and is not as commonly used.
Mod~ B is generally
used as a broadcast mode to ships by coastal maritime stations, Here are
some frequencies to try:
DAYS
12630 -12715 kHz
16860 • 17025 kHz.
19680 - 19710 kHz.
22375 • 22445 kHz.
EVENINGS '
4210- 4270 kHz.
6314 - 6345 kHz.
8415 - 8435 kHz.
12630 •12715 kHz.'
SITOR-Bmayalsobe used for the receptionofthe NAVTEXsignal at518 kHz.
• Note:
Ifthe M-400 is set in the AUTOR mode it wil! also copy SITOR-B. Even if the
transmitting station suddenly changes from SITOR A to SITOR B, copy will
continue as long as you are in the AUTOR mode. '
When trying to copy SITOR you do nothave to worry about sense (NORI
REV), speed or shift! '
Uni versal M-400 Decoder Page 13
Owner's Manual
L _

170
96
170
10.FEC-A FEC-Ais a popularEuropean pressand diplomatie mode. To
selectthe FEC-
Amode, press the FUNCTION button. The currently selected
mode of
eperation should
appear at the upper left of the LCD screen. Use the UP or
DOWN buttons to step through the various operating modes until the screen
displays FEC-A.
Press the FUNCTION button. The screen wil!
now display:
IFEC-A
The 170 indicates that the demodulator is set for a shift of 170 Hz. Use the
UP and DOWN buttonsto selectthe propershift tor the received signal (refer
to the section on
DEMODULATOR TUNING).
Press the FUNCTION button.
The screen wil! now display:
IFEC-A
The 96 indicatesthat the unit is set to decode a FEC-A signalof 96 baud. Use
the UP and DOWN buttonsto
selectthe properbaud rate (speed) torthe signal
to be received. The available speeds are 96 and
144 baud.
Press the FUNCTION button. The
M-400 is now in the Text Receive mode
tor FEC-A. Tunetor MK&SP.
FEC-A signalstake several seconds to "sync".
IFEC-A SAMPLE FREQUENCIES
Baud Shift
kHz Call
Location
96 850
123 DCF42
Bonn, Germany
96
425
10217
9VF59
Singapore (Bonn re1ay)
144
10802 DZFG
Belgrade,
Yugos1avia
96
140 11123
DFI26
Bonn, Germany
144
11483
Paris, France
144
13417 TAD
Ankara, Turkey
144
368
13427
Belgrade,
Yugos1avia
144
378 13539
Moscow, Russia
(Fr. Ernb. )
96 403
13570
Bonn, Germany
144
13833
TAD
Ankara,
Turkey
96
425
13927 DFN92
Bonn,
Germany
144
812 13982 TAD
Ankara,
Turkey
144
15794 TAD
Ankara,
Turkey
144
18184 TAD
Ankara,
Turkey
144
820 18864
TAD
Ankara,
Turkey
96
19535
9VC91
Singapore
(Bonn re1ay)
96
425
19644
Lagos,
Nigeria
96 425
20022 DFU23
Bonn,
Germany
96 400
20500
Bonn, Germany
96 425
23545
DFX54
Bonn,
Germany
96 425
23697 DFX69H6
Bonn,
Germany
96 395
25320
DFZ32
Bonn,
Germany
96
425 26441
DFZ64
Bonn,
Germany
Universal M-400 Decoder
Page 14
Owner's Manual

11.SWED-ARQ As you might suspect from the name,SWED-ARO is a diplomatic mode used
by the Swedish. To select the SWED-ARO mode, press the FUNCTION
button. The currently selected mode of operation shouldappearat the upper
left of the LCD screen. Use the UP or DOWN buttons to step through the
various operating modes until the screen displays:
I ~WED-ARQ
Note: Thescreen may
indicate Sor L rather
than M.
170
Press the FUNCTION button. The screen will now display:
I ~WED -ARQ
The 170 indicates that the demodulator is set for a shift of 170 Hz. Use the
UP and DOWN buttons to select the propershiftfor the received signa!. Press
the FUNCTION button. The M-400 is now in the Text Receive mode for
SWED-ARO. As always, tune the radio to get both the MK and SP LEDs to
blink.
When operating in the SWED-ARO mode, the SENSE button selects either
short, medium or long character block sizes. The M-400 must be set to the
same size as that being received in orderto obtain synchronization. The only
time that the M-400 indicates the current setting of the block size is on the
Mode screen display. The simplest way to set the M·400 iswhile actually
receiving a SWED-ARO signa!. Press the SENSEbutton and then waitthree
orfour transmissioncycles. Ifthe DATA LED does not turn on,then press the
SENSEbutton again. Wh ilE~ three presses of the SENSEbutton will coverall
three possible group sizes,you may need to repeat thisprocessseveraltimes
asthesendingstation maychange block sizeswhile you aretryihg to manually
sync. Once the M-400 locks on to the SWED-ARO transmission, it will track
.further block size changes automatically so you should not press the SENSE
button again unless the DATA LED turns oft.
SWED-ARQ SAMPLE FREQUENCIES
Baud Shift
kHz .
Call Location
100 170 12103 SAM
Stockholm ,
Sweden
100 42 5 13
862
SAM
St o ckh o lm, Swe den
100 17 0 14406 SAM
Sto ckho lm, Swe den
100 370 14523
SAM
St ockholm, Swed en
100 425 14814
SAM
Sto ckholm, Swede n
100
400
14878 SAM
Stockholm, Sw ed en
10 038 5
14970
S AM
St oc k ho lm, Swede n
100
425
18033
100 170 18810
SAM
St oc kh ol m, Swe den
100
18 947
SAM
Stockhol m, Sweden
100
39 5 20 699
SAM
Lisbon ,Po
rt ugal
10 0170 20960 SAM
St ock ho lm, Sweden
10 0 425 20986
SAM
Sto c kh ol m, Sw ede n
100 23505 SAM
Stockhol m,
Swed en
100 400
23 547
SAM
Stockhol m, Swede n
100 450 2358 6 H ar ar e,
Zimb abwe
100
400
2359 3 SAM
S to c kho lm, Swe de n
Universal M·400 De coder
Page 15
owners Manual

Press the FUNCTION button.
the next FAX image to start.
12.FAX Facsimile (FAX) mode is used on shortwave to transmit wire photos.weather
charts, maps and other documents. The M-400 can decade such transmis-
sions and print them to a standard dot matrix parallel printer (not supplied).
The printer must be Epson graphics compatible (98% of today's PC printers
are.). The M-400 does not support laser printers.
If yaur dot matrix printer has an 8 or 9 pin print head, you may :proceed
directly. If your dot matrix printerhas a 24 pin print head, you must first go to
the Programming section (Chapter 21) of this manual, and set the M·400
printer port for 24 pin output.
To select the FAX mode, press the FUNCTION button. The currently
selected mode of operation should appear at the upper left of the LCD
screen. Use the UP orDOWN buttons to step through the various operatinq
mades until the screen displays:
INote: The screen
120 may indicate NEG
576 rather than POS.
----------
The M·400 will now wait for the beginning of
Waiting for the start of the image to occur wil! insure the image is jproperly
framed. However, you may begin to print an image "mid-stream" if
~ou wish.
Simply press the UP button to manually start (or stop) FAX decoding. Yau
will see the DATA LED light.
If you begin to print an image mid-stream (or miss the framing header) your
image will not be properly centered. For example, the left border rnight run
down the center of the page. You can manually re-frame the
imag~ "on the
fly" by pressing DOWN button one or more times. Each press of
th~ DOWN
button will more the image left by 1/2 inch. .
If the image starts to appear as a "negative" on the printer you can ~ress the
5EN5E button. This will change the polarity of the printed image. BÎack lines
or areas will become white and white Iines or areas will become olack. This
can also be done during reception ("on the fly"). ;
The M-400 receives frequency modulated FAX at a tixed speed ot ~ 20 LPM
and a tixed IOC ot 576. This speed IOC combination will decade 95% of the
available shortwave FAX imagery.
Tuning FAX is more of an art than a science. The M-400for is tairly
~orgiving
when tuning FAX. Trial and error is the key here. Simply watch the printer,
and make minoradjustments to your receiver's tuning knob to enhance the
image.
In order to get a goodFAX image, you must have a strong signa!. i
Un iversal M·400 Decoder
Page 16
oljmer's Manual