Hal Communications ARQ1000A User manual

Copyright
Illinois.
© 1987
Printed
rights reserved.
reproduced in any
copyright owner.
A R Q 1 0 0 0 A
ERROR CORRECTION TERMINAL
by HAL Communications Corp., Urbana,
in the United States o£ America. All
Contents o£ this publication may not be
form without the written permission o£ the
870-01000
December, 1987, Printing

ARQ1000A ERROR CORRECTION TERMINAL
CONTENTS:
INTRODUCTION . • • • • . . . . . . . . . . . . . . 1
CHAPTER 1.
UNPACKING AND INSPECTION 2
CHAPTER 2. INSTALLATION . • • • • • • • • • • • • • • • • • • 5
2.1 PRELIMINARY INSTALLATION CONSIDERATIONS • • • 5
2.1.1 MECHANICAL REQUIREMENTS • • • • . • • 5
2.1.2 ELECTRICAL REQUIREMENTS • • • • • • • 5
2.1.3 REAR PANEL CONNECTIONS • • • • • • • • 6
2.2 TTY TERMINAL INTERFACE • • • . • • • • . •• 12
2.2.1 SELECTION OF TTY TERMINAL •••••• 12
2.2.2 TERMINAL CONNECTIONS •••.••••• 15
2.2.3 CONNECTION TO HAL DS3200 ••.•..• 17
2.3 DEMODULATOR CONNECTIONS • • • • • • • . • • • 18
2.3.1 SWITCH SELECTION ••••••••••• 18
2.3.2 CONNECTIONS TO HAL DEMODULATORS ••• 19
2.4 TRANSMITTER AND RECEIVER CONSIDERATIONS • • • 21
CHAPTER 3. OPERATING THE ARQ1000A • • • • • • . • • • • ••• 25
3.1 ARQ1000A FRONT PANEL •••.•••••••• 25
3.1.1 MODE CONTROL ••••••••••••• 25
3.1.2 TRANSMISSION CONTROL SWITCHES •••• 26
3.1.3 SYSTEM INDICATION AND CONTROL •••• 26
3.1.4 DATA INDICATORS ••••••.•••• 28
3.1.5 WRU AND HERE IS SWITCHES .•••••• 29
3.2 PROGRAMMABLE FEATURES OF THE ARQ1000A • • • • 30
3.2.1 ENTERING PROGRAM MODE •••••••• 30
3.2.2 PROGRAMMING COMMANDS AND FORMAT • • • 31
3.2.3 PROGRAMMING THE HERE IS MESSAGE •.• 32
3.2.4 PROGRAMMING THE IDENTIFIER CODES • • • 32
3.2.5 CS X/1 CONTROL SIGNAL PARAMETER • • • 33
3.2.6 EC ON/OFF TERMINAL ECHO PARAMETER .• 34
3.2.7 TIME OUT <TO> PARAMETER ••••.•• 35
3.2.8 WRU CONTROL COMMAND • • . • • • • • • 35
3.2.9 DEFAULT AFTER RESET PARAMETERS • • • • 35
3.2.10 CONVERSATIONAL FEC <CF:> ••••.•• 36
3.2.11 TRANSMIT DELAY <TO:> .••.••••• 37
3.2.12 CONTROL DELAY <CD:> ••••••••• 38
3.2.13 AUDIO DELAY <AD:> •.•••••••• 39
3.2.14 BUFFER CLEAR <BC:> •.•••••.•. 39
3.2.15 ST: LIST STATUS COMMAND ••••..• 40
3.2.16 EX: EXIT PROGRAMMING COMMAND ••••• 40

p======================c=======----- -
3.3 OPERATING
INSTRUCTIONS . . . . . . . . . . .
41
3.3.1 HELP PAGE
. . . . . . . . . . . . . .
41
3.3.2
TO RECEIVE ARQ OR FEC MESSAGE
41
3.3.3 TO SEND ARQ MESSAGE
. . . . .
42
3.3.4
TO SEND FEC MESSAGE
. . . . . . .
43
3.3.5
CONVERSATIONAL FEC
. . . .
44
3.3.6
MONITOR MODE
. . . . . . . . .
45
3.3.7
OFF MODE
. . . . . . . . .
45
3.4
OPERATION WITH DS3200
AND ST8000 . . . . 45
3.5 OPERATION WITH DS3200
AND ST6000
. . . . . . 47
CHAPTER 4. THEORY OF OPERATION • • • • • • • •••• 48
CHAPTER 5.
CHAPTER 6.
CHAPTER 7.
APPENDIX A
APPENDIX B
APPENDIX c
APPENDIX D
APPENDIX E
4.1 THE ARQ COMMUNICATIONS SYSTEM - AN OVERVIEW • 48
4.2 COMPARISON BETWEEN ARQ AND RTTY .•••••• 48
4.3 ARQ MODE •••.•••.••••••••.• 54
4.3.1 SELECTIVE CALLING IN ARQ MODE •••• 55
4.3.2 TEXT TRANSMISSION AND ERROR CORRECTION 56
4.3.3 CHANGING DIRECTION OF TRANSMISSION •• 57
4.3.4 END OF COMMUNICATIONS •.••••.• 58
4.3.5 IDLE CHANNEL SIGNALS .•••.•.•• 59
4.4 FORWARD ERROR CORRECTION <FEC> • • • 59
4.4.1 TEXT TRANSMISSION IN FEC MODE. 59
4.4.2 ERROR CORRECTION IN FEC MODE ••.•• 60
4.4.3 BEGINNING OF TRANSMISSION .••••• 61
4.4.4 END OF FEC TRANSMISSION .•• 62
4.4.5 CONVERSATIONAL FEC MODE .•..••• 62
4.5 SEL-FEC MODE ••..•••.•.•••. 63
4.6 STANDBY MODE • . . • • • • . •• 63
4.7 MONITOR MODE • • • • • . • • • . ••.• 64
4.8 "OFF" MODE . • • . . . • • • . • . • 64
4.9 PROGRAMMABLE DELAYS • • • • • .••• 65
IN CASE OF DIFFICULTY •.•••
5.1 CARE OF YOUR ARQ1000A •
5.2 TYPICAL OPERATIONAL PROBLEMS
5.3 REPAIR PROCEDURES
5.4 USER ADJUSTMENTS
TECHNICAL DATA . • • • •
6.1 CIRCUIT DESCRIPTION •
6.2 CIRCUIT DIAGRAMS
SPECIFICATIONS • . . • •
POWER TRANSFORMER CONNECTIONS
DEFINITION OF SIGNAL POLARITIES
CCIR
491 TRANSLATION TABLE
.
REFERENCES
. . . . . . . . .
QUICK OPERATOR'S
GUIDE
. . . .
LIMITED WARRANTY
.
.
• • . . . • • • • 67
• • • • • • • 6 7
. . . . . . . . 68
. . . . . . . 71
• • • 72
. 73
• • 73
• • • • 74
• • 85
. . . . . . .
89
. . . . .
91
. . . . .
92
. . . . . . .
93
. . . . . . . . .
95
• 97

ARQ1000A
PAGE 1
INTRODUCTION
This manual describes the installation and operation o£ the
HAL ARQ1000A Error Correction Terminal. The ARQ1000A has been
designed £or convenient and straight£orward customer use. Many
£eatures are sel£-explanatory £rom a close examination o£ the
ARQ1000A £ront and rear panels. However, like many
sophisticated electronic devices, there are some £eatures and
operator techniques which you may not understand until you have
read this manual. You should plan to devote some time becoming
£amiliar with the ARQlOOOA be£ore using it on the air.
NOTE! The ARQlOOOA will NOT work correctly until the correct
I/0 switch settings have been made. Please read Chapter 2
care£ully and make the appropriate switch selections be£ore
attempting operation.
Figure 1
The ARQ1000A

ARQ1000A
UNPACKING AND INSPECTION
PAGE 2
CHAPTER 1
UNPACKING AND INSPECTION
When
unpacking the ARQ1000A, care£ully inspect the shipping
carton and the cabinet £or shipping damage. Any evidence
o£ shipping damage should be immediately reported to your
supplying dealer or shipping carrier. Be sure to save all
packing materials i£ damage is £ound - the shipping carrier will
want to inspect them £or any insurance claim. Be£ore
discarding the packing materials check that all parts and
accessories are accounted £or. Check the accessories against
the £ollowing list. I£ any are £ound missing, double-check
the packing £or loose parts and then noti£y either your dealer or
HAL Communications Corp. o£ the shortage. Please speci£y the
HAL part number!
Accessory parts:
Accessories Packed With ARQ1000A:
1 -
770-05001 1/2 Amp Slow-blow Fuse
1 -
333-17250 AC Power Cord
1 -
870-01000 ARQ1000A OPERATOR's MANUAL
1 -
333-10250 DB-25S
External Modem Connector
1 -
333-20250 DB-25P Terminal Connector
2 - 333-51228
25-pin Connector Shell
3 -
333-74564 D Connector Hardware
1 -
333-20090 DE-9P Radio Connector
1 -
333-51218 9-pin Connector Shell
Additional Options Available £or ARQ1000A:
M1700 Modem
Option £or 1700 Hz +/- 85 Hz; installs inside
ARQ1000A. Includes receive demodulator and transmit
tone generator. All external connections are made
to DE-9 connector on ARQ-1000A rear panel. User
installable option.
LP1200A High voltage loop power supply. Neutral or polar
<0-120V or -60/+60V>, 20 or 60 ma. Optically
isolat~ RS232C I/0. Separate cabinet; 3.5-inch
high rack mount design. User installable.

ARQ1000A
UNPACKING AND INSPECTION
PAGE 3
In addition to these accessories, you will need the £ollowing
items to complete the ARQ station:
•
1. An RTTY modulator/demodulator capable o£ operation at a data
rate o£ 100 baud. This unit may be a HAL ST-8000, ST6000, or the
M1700 accessory demodulator board installed in the ARQ1000A. The
standard tone £requencies used in marine ARQ service are 1700
Hz, +/-85 Hz. The M1700 is normally supplied £or these
£requencies and the ST6000 can be supplied £or these £requencies
on special order. The ST-8000 is a £ully tunable modem and can
be set by the user to any tone set. Other high quality
modulator/demodulator systems may also be used with the ARQ1000A
i£ they <1> inter£ace to TTL or RS232C data circuits, <2>
have totally separate data connections £or transmit and receive
data, and <3> have bandwidth and low pass £ilter su££icient
to process 100 baud data. A good tuning indicator is also
recommended, especially i£ the system is to be used with a
variable tuning receiver. This will aid in determining i£ the
receiver is set on the exact £requency. ARQ systems must
typically be tuned very accurately in order to operate
correctly. The ST-8000 and ST6000 each include a tuning
oscilloscope. The SPT-1 Spectra Tune tuning indicator is highly
recommended when the M1700 or other modem without a tuning
indicator is used.
2. A teleprinter or video terminal that can operate using the
Baudot or ASCII code at data rates between 45 and 300 baud. The
ARQ1000A can be directly connected to the HAL DS3200
Communications Terminal. Any high quality Baudot or ASCII
terminal may also be used with the ARQ1000A i£ the £ollowing
conditions are met: <1> data rate o£ 45, SO, 57, 74, 110,
134.5, 150, or 300 baud; <2> Baudot <ITA No. 2) or ASCII
code; and (3) inter£ace to RS232C or TTL voltage levels. I£ a
high voltage loop terminal is to be used, the LP1200A Loop Power
Supply should be used. The ARQ1000A terminal "echo" may be
selected on or o££ so that a terminal with or without local echo
may be used. A data inhibit control line <CTS in RS-232
systems> is also desirable £or tape and other automated message
transmitting systems.
3. A transmitter and receiver system that is capable o£ rapid
switching between transmit and receive conditions. In general,
delays in switching must all be 20 ms or less £or satis£actory
ARQ mode operation. Many transceivers will NOT meet these
requirements. Some modi£ications or a change in equipment may be
required to use the ARQ1000A with transceivers in particular.
HAL may be able to provide some additional in£ormation about
equipment capabilities, but it is the user's responsibility to
assure that switching times are adequate. 0£ course, the
transmitter must also be capable o£ operation with a 100~
duty cycle when the FEC and SEL-FEC modes are used.
-

ARQlOOOA
UNPACKING AND INSPECTION
PAGE 4
RADIO SIGNALS
RECEIVER
TRANSMITTER
RF
SYSTEM
RECEIVER
TRANSMITTER
RX
TONE
RXD
CONTROL
ARQIOOOA
PR\NTER
_RX
TONE
TX
TON
TONE
MODEM
DEMOOULATOR
TONE KEYER
TXD-
-RXD
ARQ CODE
CONVERSION /GENERATION
IL~---~'
CONTROL
ARQIOOOA
TERMINAL
EQUIPMENT
PRINTER
TXD
Figure 2. A typical ARQ communications system.

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ARQ1000A INSTALLATION
PAGE 5
CHAPTER 2
INSTALLATION
2.1 PRELIMINARY INSTALLATION CONSIDERATIONS.
The HAL ARQ1000A is a versatile instrument that may be used to
adapt a radio communications sytem £or transmission and
reception o£ the Moore/ARQ 7-unit error correcting digital
code. The basic radio communications system consists o£ a
radio transmitter, radio receiver, antennas, tone demodulator
£or received data, tone encoder £or transmit data, a
keyboard and printer <TTY terminal>, and the ARQ1000A Error
Correction Terminal. The transmit-receive £unctions o£ the tone
demodulator and encoder devices are o£ten combined into a single
unit that may be called a '"modem.'", '"dem.odulator'", or "terminal
unit''. The ARQ1000A may be inter£aced directly to external
'"demodulators'" or a circuit board option, the M1700 Demodulator,
may be installed in the ARQ1000A cabinet. Since the
inter£acing requirements o£ each demodulator and
keyboard/printer terminal may be di££erent, a number o£ user-
selectable switches are provided in the ARQ1000A to match the
speci£ic I/0 requirements o£ your equipment. The majority o£
this chapter will discuss the possible inter£ace selections in
detail. The ARQ1000A will be ready £or operation only a£ter
all inter£ace requirem.ents have been determined and the
appropriate switch settings selected. Be£ore the I/0
selection is discussed, a £ew preliminary installation
details should be de£ined.
2.1.1 MECHANICAL REQUIREMENTS.
The ARQ1000A is housed in a cabinet that may be used in
either table-top or rack-mounting applications. The basic
cabinet measures 3.5'' high <8.9 em.> by 16.75'" wide <42.5 em> by
10.0'" deep <25.4 em>. The complete unit weighs 8 lbs <3.6
kg>. Addition o£ the M1700 option adds no dimension and
approximately 1 lb to the weight. The ARQ1000A may be rack
mounted in a standard 19'" wide equipment rack or mounted on a
table top as required. When rack mounted, the ARQ1000A requires
3.5'' o£ vertical panel space. Since the ARQ1000A consumes little
power, cooling requirements are not stringent. However, when
installing in a rack, try to avoid blocking air£low to the top
and bottom. sur£aces o£ the cabinet.
2.1.2 ELECTRICAL REQUIREMENTS.
The ARQ1000A may be operated £rom AC power mains with
between 105 to 130 or 210 to 250 volts, 50 or
It requires approximately 30 watts o£ AC power. The
voltages
60 Hz.
unit is

ARQ1000A INSTALLATION
PAGE 6
furnished factory wired for 120 VAC, 60 Hz. The ARQ1000A can be
supplied from the factory with 220 VAC, 50 Hz wiring if
specified. In either case, the unit may be be modified by the
user for operation from 105 to 130 VAC or 210 to 250 VAC, as
described in APPENDIX A of this manual. If a mains voltage other
than 120 VAC is set at the factory, it will be so noted on
a small label on the rear panel, near the AC power input
connector. The AC power input connector is the
international standard for three conductor non-captive power
cords. As will be discussed in Chapter 3, all programmable
features such as selective call codes, etc. are stored in an
EEPROM so that they are not lost if ac power fails. The initial
power-on start-up mode is also programmable so that the ARQ1000A
may
be set to always return to a preset mode when power is
restored. No internal or external support batteries are
required for the ARQ1000A. The ARQ1000A has a full front panel
with 30 indicators and 12 switches. Although all front panel
switch functions may be remotely set by keyboard programming on
the TTY terminal, it will be advantageous in most
installations to mount the ARQ1000A in such a location that the
indicators may be observed by the operator from time to time.
When the ARQ1000A is mounted an appreciable distance from the
TTY terminal, demodulator, or transmitter and receiver, it is
strongly advised that shielded cabling be used to minimize RF
and noise induction onto the data signals. If cable distances
greater than 50 ft. are required, it may be advisable to
consider use of balanced line drivers and receivers to minimize
RF and noise problems. In particular, use of TTL data
connections for long cables is NOT advised.
2.1.3 REAR PANEL CONNECTIONS
The rear panel of the ARQ1000A is shown in Figure 3. With the
exception of the AC power input, ALL I/0 connections are
made to the three "0" style connectors. When the ARQ1000A is
used with an external receive demodulator and transmit tone
keyer, all connections are made to the two 25-pin connectors. The
9-pin connector is only used when the M1700 modem option is
installed.
When connecting the ARQ1000A, be sure to use grounding style
of AC power distribution as this provides the required safety
ground system. In addition, since the ARQ1000A will be used
with radio transmitters and receivers, a good RF ground
system should also be installed. A low-inductance, short length
RF ground lead should connect between all equipment in the
system. A .25" or wider shield braid or copper strap is highly
recommended for the RF ground return; attach it directly to the
ground binding post on the ARQ1000A rear panel. If problems
with RF interference to or from the ARQ1000A are encountered,
please request the HAL application note "R.F. Induced Problems
And Solid-State RTTY Terminals."

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ARQ1000A INSTALLATION
PAGE 8
Inter£acing the ARQ1000A to the rest o£ the system invloves two
steps: <1> making the physical wire connections and <2>
making the proper internal switch settings to match the required
I/0 inter£ace o£ your equipment. Switch settings will be
discussed in sections 2.2 and 2.3 o£ this chapter. The rear
panel connections and their uses are outlined below:
TERMINAL CONNECTOR:
PIN 1 - FRAME GROUND: Direct Connection to the ARQ1000A
cabinet £or grounding o£ a shielded cable between
the terminal and the ARQ1000A.
PIN 2 - KEYBOARD DATA INPUT: Input signal £rom terminal
or £rom keyboard, i£ separate keyboard and printer
units are used. Accepts standard RS232 Transmit
Data <TXD> line or TTL signal. TX/RX DATA switches
must be set properly. <See Section 2.2.>
PIN 3 - PRINTER DATA OUTPUT: Output signal £rom ARQlOOOA
to terminal or printer. Drives standard RS232
Receive Data <RXD> line or TTL device. TX/RX DATA
switches must be set properly.
PIN 4- REQUEST TO SEND <RTS>: Input £rom terminal to
ARQlOOOA. Can be used as Transmitter PTT control
when ARQ unit is in OFF mode by setting jumper J3
to the RTS position. <See Section 2.2.>
PIN 5 - KEYBOARD WAIT: Control signal £rom ARQlOOOA to
terminal or keyboard which provides £low control
£or data being transmitted. This signal is active
when the £irst 80 characters o£ the ARQlOOOA bu££er
are £illed. Drives standard RS232 Clear to Send
<CTS> line or TTL device. Highly recommended i£
terminal has the capability!
PIN 7 - SIGNAL GROUND: Provides standard RS232 signal ground
connection to terminal.
PIN 19 - TERMINAL KOS: Input signal £rom the terminal to the
ARQlOOOA to key the transmitter i£ the ARC unit is
to be used in the OFF mode £or standard ASCII or
Baudot teleprinter operations. Not normally used in
SITOR operations.
PIN 20 -PRINTER WAIT: Control signal £rom terminal or
printer to inhibit data coming £rom the ARQ1000A.
Normally set £or No Connection in most systems, as
virtually all terminals and printers are able to
receive the e££ective throughput o£ approx. 50 b/s
in SITOR. Accepts standard RS232 Data Terminal
Ready <DTR> signal or TTL.
1

ARQ1000A INSTALLATION
PAGE 9
EXTERNAL MODEM CONNECTOR: <NOTE: This connector is typically
used only i£ an external modem is connected; not normally
used i£ the M1700 Modem option is installed.)
PIN 1 - FRAME GROUND: Direct connection to the ARQ1000A
cabinet £or grounding o£ a shielded cable between
the terminal and ARQ1000A.
PIN 2- TRANSMIT DATA <TXD>: Data output £rom ARQ1000A to
modem £or transmission. Can be RS232 or TTL signal.
PIN 3- RECEIVE DATA <RXD>: Receive data £rom modem to
ARQ1000A. Can be RS232 or TTL signal.
PIN 7 - SIGNAL GROUND: Provides standard RS232C signal
ground between modem and ARQ1000A.
PIN 19 -TX/RX CONTROL: Provides transmit-receive switching
to external modem i£ required; either open NPN
collector <O.c •• low=transmit> or TTL <high=
transmit>; factory set to O.C. <Jumper J6>.
PIN 22 -TRANSMITTER PTT: Push-To-Talk control £rom the
ARQ1000A to the modem. i£ modem is so equipped. £or
controlling the transmitter PTT circuit. I£ no PTT
connection is made through external modem. then the
PTT control line on the Radio Connector <PIN 4> may
be used.
PIN 23 - EXTERNAL SCOPE MARK: For use when M1700 internal
modem is installed. Output £rom ARQ1000A which can
be used with an external oscilloscope <along with
pin 24> to provide a visual presentation o£ the
received signal. This signal is normally £ed to the
"x" axis input o£ an x-y input oscilloscope.
<Nominal 1000 ohms. 1.0 v P-P>
PIN 24 - EXTERNAL SCOPE SPACE: For use when M1700 internal
modem option is installed. Output £rom ARQ1000A
which is £ed to the "y" axis o£ an x-y input~
oscilloscope <used along with pin 23>.
<Nominal 1000 ohms. 1.0 v P-P>
-----~----~-~----- ----- ----------------

ARQ1000A INSTALLATION
PAGE 10
RADIO CONNECTOR:
PIN 1 - AUDIO INPUT: Input from receiver audio.
PIN 2 - AUDIO IN GROUND: Second audio input terminal for
balanced audio connection to receiver. NOTE: I£ only
a single receive audio terminal is provided on the
receiver <unbalanced audio>, this pin should be
connected to ground.
PIN 4 - TRANSMITTER PTT: Push-To-Talk control from the
ARQ1000A to the transmitter. Carries the same signal
as pin 22 on the External Modem connector, but
designed for direct connection to the transmitter
PTT line when the M1700 is installed.
PIN 6 - SELCAL OUTPUT: Control line from ARQ1000A which
becomes active <low> when the Selective Call loaded
into the ARQ1000A <parameter "LC"> is received in
ARQ or SEL FEC modes.
PIN 7 - GROUND
PIN 8 - AUDIO OUT: Output to transmitter audio connections.
PIN 9 - AUDIO OUT GROUND: Second audio output terminal for
balanced audio connections to transmitter. This pin
is to be grounded i£ the transmitter supports only
unbalanced <single wire> audio.
The I/0 interface standards used on the ARQ1000A connections are:
RS232C:
TTL:
OPEN
COLLECTOR:
<O.C. >
Mark voltage
=
-5 to -12 VDC
Space voltage
= +5
to
+12 VDC
Source resistance
=
300 ohms maximum
Load resistance
=
3000 to 7000 ohms
Load
capacitance
=
2500 pF maximum
Mark voltage = +3.5 to + 5 VDC
Space voltage = 0 to + 1.5 VDC
Output capability = 20 mA <7408)
Input loading = 1 mA <7408>
NPN transistor <2N5655)
Open-circuit voltage = 10 to 200 VDC
Open-circuit resistance = 10,000 ohms min.
Closed-circuit current = 10 to 100 mA
Closed-circuit resistance = 10 ohms max.
Will ONLY switch positive voltage circuits.

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ARQ1000A INSTALLATION
TD-3 SDCKCTI
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M!700
ARQ!OOOA LOGIC BOARD
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EXPLODED VIE\./ OF DIP
S\JITCH SETTINGS
U30 U26 U25
I~
U27 I I
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MODEM
TX/RX PNTR
KBD
DATA
\JAIT \JAIT
I I
S\Jl
Settings shown £or: RS232 Terminal <Keyboard and Printer>
RS232 Keyboard Wait
N/C Printer Wait
M1700 Internal Modem selected
Code & Data Rate= 50 Baud·Baudot
FIGURE 4. I/0 SWITCH LOCATIONS
PAGE 11

ARQ1000A INSTALLATION
PAGE 12
2.2 TTY TERMINAL INTERFACE.
The ARQ1000A with the M1700 Demodulator option requires
only a teleprinter or video terminal and the transmitter-
receiver to make a complete ARQ communications system.
Conversely, the ARQ1000A without the M1700 Option may be used
as a code conversion device to convert a standard Baudot or
ASCII radio teleprinter station into an ARQ station. In
either case, the data code) rate, and electrical interface
parameters of the terminal and ARQ1000A must first be
matched.
The ARQ1000A may be set with internal switches to interface the
following terminal parameters:
Data Code:
Data Rate:
Interface:
Control:
ASCII or Baudot <ITA No. 2 or U.S. Baudot>
45, SO, 57, 74, 110, 134.5, 150, or 300 baud
RS232C or TTL; separate connections for
keyboard and printer.
Printer Wait <RS232C or TTL, either polarity>
Keyboard Wait <RS232C, TTL, or open-collector;
either polarity>
These parameters are chosen by switches inside the ARQ1000A.
The location of these switches is shown in Figure 4.
2.2.1 SELECTION OF TTY TERMINAL.
Either an ASCII or Baudot encoded TTY terminal may be used with
the ARQ1000A at any of the data rates shown above. The
terminal should have an I/0 interface for RS232C or TTL data
circuits. If a high voltage loop terminal is to be used, a loop
interface such as the LP1200A is required. Most commercial
terminals and personal computers can be interfaced to the
ARQ1000A with little trouble. If the ARQ1000A is to be used in a
commercial "SITOR" system, it is recommended that your terminal
use SO baud Baudot as this will then work directly for normal
RTTY when "SITOR" type communications are not required.
Otherwise, you may want to use 110 or 300 baud Baudot or ASCII
for the terminal since this wlll noticeably improve the
speed at which the ARQ1000A may be reprogrammed. 45 baud
Baudot may be used, but may give some confusing situations on
receive because the printer operates slower than the ARQ code
through-put <no error or FEC conditions>.

I
ARQ1000A
Control
ARQ1000A.
INSTALLATION
or "handshaking" connections
These control signals are:
are
PAGE 13
provided
on
the
1. PNTR WAIT: A signal from the printer to the ARQ1000A that
indicates a printer busy condition.
2. KBD WAIT: A signal from the ARQ1000A to the keyboard or
data transmit device that indicates that the
ARQ1000A input buffer is full and data input
should temporarily halt.
The PNTR WAIT signal may be either RS232C or TTL, o£ either
polarity. The PNTR WAIT signal will not be required £or any but
the slowest o£ printers. Since the maximum through-put o£ the
ARQ communications system is 6.67 characters per second, few
printers will require this control signal. It may be useful,
however, in computer storage applications where disk
operations must temporarily interrupt data collection.
The KBD WAIT signal is most advantageous when an electronic data
message storage device is used. The KBD WAIT signal may be
RS232C, TTL, or open-collector o£ either polarity. The
Open-collector connection may be used to switch positive DC
voltages to ground within the maximum limitations o£ 200V open-
circuit and 0.1 amp. closed circuit. Use a control relay
i£ your keyboard control requires voltages or currents beyond
these limitations. It is recommended that you now review your
terminal's specifications and £ill-out the following form
which will be used in selection o£ proper jumpers on the I/0
plugs. IF you are using a HAL DS3200, specific settings will be
presented later in this chapter.

ARQ1000A INSTALLATION
TABLE 1
TTY TERMINAL PARAMETERS
TERMINAL MFGR AND MODEL:
DATA RATE CHOSEN:
DATA CODE: ASCII BAUDOT
PNTR I/0: RS232C
<mark = negative voltage>
TTL <mark = logic high: +V)
KBD I/O: RS232C <mark = negative voltage)
TTL <mark = logic high>
PNTR WAIT: REQUIRED?
<yes/no)
RS232C WAIT
=
<mark
or space>
TTL
WAIT
=
<high or low>
KBD WAIT: REQUIRED?
<yes/no>
RS232C WAIT
=
<mark
or
space>
TTL WAIT
=
(high
or low>
OPEN COLLECTOR POSITIVE VOLTAGE __ <yes or no>
VOLTAGE LESS THAN 200 VDC __ <yes or no)
CURRENT LESS THAN 100 ma __ <yes or no)
PAGE 14
(i£ any o£ the above are "NO", use a relay £or control)
WAIT =
<open or closed circuit)

1.
I
l
ARQ1000A INSTALLATION
PAGE 15
2.2.2 TERMINAL CONNECTIONS.
Mow that the parameters o£ your TTY terminal have been
de£ined in Table 1, the required switch selections £or the
ARQ1000A can be made. Two 7-position and two 4-position DIP
switches must be set £or the proper terminal I/0 parameters.
Re£er to Figure 4 £or the location o£ the switches. In addition,
you may select either standard RS232 RTS <Request To Send> or
terainal KOS <Keyboard Operated Switch> to be used £or
transmitter PTT control when in the o££ mode £or standard TTY.
DATA CODE AND RATE:
The data code and rate are set with the £our switches on SW1
located near the right hand side o£ the main circuit board
<see Figure 4.>. The £our switches are set as de£ined in Table 2
below:
TABLE 2. TERMINAL CODE AND RATE SWITCHES
BAUD RATE
SWITCHES ON or CLOSED
45
2,3, 4
Switch Function
50
3,
4
1
set code
57
2,
4
2--,
74 4
3-...;-- set data
110
2,
3
4-..J
rate
134.5
3
150
2
300
(2,3,
and 4 all OFF>
Turn no. 1 .. ON .. £or Baudot, turn .. OFF.. £or ASCII
TERMINAL INTERFACE <TX/RX DATA>:
The data connections to the terminal are set by the Switches o£
U27 labelled ..TX/RX DATA... The switches are set according to
Table 3 below:
TABLE 3. TERMINAL TX/RX DATA SWITCHES
/
I/0 INTERFACE
RS232
TTL
SWITCHES
ON
1, 3
2, 4

ARQ1000A INSTALLATION
PAGE 16
PRINTER WAIT CONTROL SIGNAL:
This control signal will generally not be required.· However, i£
your system has need o£ this signal, set the switches as
shown below in Table 4. NOTE! Switch 2 is required i£ PNTR WAIT
is not used!
TABLE 4. PNTR WAIT CONTROL SWITCHES
PNTR WAIT SIGNAL SWITCHES
ON
RS232C <-V = wait)
RS232C (+V = wait)
TTL <high = wait>
TTL <low = wait>
No PNTR WAIT req'd
KBD WAIT CONTROL SIGNAL:
3,
5
1, 5
3,. 7
1, 7
2
The KBD WAIT signal is used to control the £low o£ characters
£rom the terminal into the ARQ1000A. This is most help£ul when
transmitting a stored bu££er £rom an electronic terminal where
the number o£ characters exceeds 80. Wh~n conditions are poor on
the radio £requency link, tra££ic £low may be slowed and a risk
o£ lost text exists i£ the text is lengthy. The KBD WAIT signal
avoids this by inhibiting text transmission £rom the terminal to
the ARQ1000A when the 80 character initial bu££er o£ the ARQ unit
is £ull. The ARQ1000A allows a great deal o£ £lexibility £or
this control signal so that many variations may be accommodated.
Switch selections £or the KBD WAIT signal are shown in Table 5.
TABLE 5.
KBD WAIT CONTROL SWITCHES
KEYBOARD WAIT
SIGNAL SWITCHES ON
RS232C <-V =
wait> 3, 5
RS232C (+V =
wait)
1, 5
TTL
<high
= wait>
3,
6
TTL
<low = wait)
1, 6
o.c.
<open
ckt
=
wait> 3, 7
o.c. (closed ckt
= wait) 1, 7
I
. ~

r
I
r
I
ARQlOOOA
INSTALLATION
PAGE 17
RTS/KOS TRANSMITTER CONTROL:
I£ the system will be used to transmit standard Baudot or ASCII
code with the ARQlOOOA in the OFF mode, you may choose whether
RTS or KOS £rom your terminal will be used to turn on the
transmitter PTT £or automatic switching to transmit £rom receive.
This is done by selecting the proper location £or jumper J3. J3
is located near the right side o£ the main circuit board <the
side nearest the trans£ormer>. It labelled RTS and KOS
indicating the appropriate positions £or the jumper supplied.
Factory standard is to set J3 £or RTS. I£ your terminal is
equipped with an automatic KOS which is designed to ground the
PTT line o£ a transmitter, you may wish to switch this jumper to
the KOS position. The £actory-supplied RTS setting is standard
£or most RS232 terminals.
It now remains to connect the physical wires between the
ARQlOOOA and the TTY terminal equipment. Since a radio system
is involved, it is recommended that shielded cabling be used £or
these connections. All terminal connections to the ARQ1000A are
made to the DB-25 TERMINAL connector on the rear panel.
2.2.3 CONNECTION TO THE HAL DS3200 RADIO COMMUNICATIONS TERMINAL
The HAL DS3200 is ideally suited £or use as an ARQ I/0 terminal.
RS232 connections are used between the ARQ1000A and the DS3200 as
shown in £igure 5. The DS3200 makes use o£ the KBD WAIT signal
but does not require the PNTR WAIT signal.
ARQ1000A TERMINAL
CONNECTOR
DS3200 SERIAL I/0
CONNECTOR
PIN 1 -----------------------------PIN 1
<Frame Ground>
PIN 2 -----------------------------PIN 2
<TXD - KBD DATA>
PIN 3 ----------------~------------PIN 3
<RXD - PNTR DATA>
PIN 4 -----------------------------PIN 4
<RTS - Request To Send>
PIN 5 -----------------------------PIN 5
<CTS - KBD WAIT>
PIN 7 -----------------------------PIN 7
<Signal Ground>
FIGURE 5. DS3200 TERMINAL CONNECTIONS TO ARQlOOOA