Hal Communications DXP38 User manual

-·
"
•
LJ~~as
HF RADIO DSP MODEM
OPERATOR'S
MANUAL
Copyright 1998 ©by HAL Communications Corp., Urbana, Illinois. Printed in the United States of America. Contents of
this publication may not be reproduced in any form without the written permission ofthe copyright owner.
HAL990308
870-13800
March
8, 1999 Printing
DXP38 MANUAL
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Chapter 1.
Chapter 2
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Chapter 3
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HAL990308
Table Of Contents
Introduction
1.1 The DXP38 Manual................................................................... 1-1
1.2 DXP38 Software........................................................................ 1-1
1.2.1 Minimum Requirements ............................................... 1-2
1.2.2 Software and Documentation Up-Date........................ 1-2
Installation and Set-Up
2.1
2.2
2.3
2.4
2.5
Unpacking
and lnspection......................................................... 2-1
DXP38 Rear Panel Connections...............................................2-2
2.2.1 Audio lnput...................................................................2-2
2.2.2 Audio Output ................................................................2-4
2.2.3 PTT Output...................................................................2-4
2.2.4
FSK Output ..................................................................2-5
2.2.5 SEL-CAL Output ..........................................................2-6
2.2.6 RS-232 Connections....................................................2-6
2.2.7 Ground Connection ......................................................2-7
2.2.8
DC Power Connection .................................................2-7
Initial Transmitter
and Receiver Adjustment .............................2-7
Front
Panel Status and Tuning Indicators ................................2-9
2.4.1 Status Indicators ..........................................................2-9
2.4.2 Tuning Indicator- MIS Mode........................................2-9
2.4.3 Tuning Indicator- M Mode...........................................2-9
2.4.4 Print Squelch lndicator...............................................
2-11
Special Considerations When Operating CLOVER ................ 2-11
2.5.1 Transmitter and Receiver Requirements ................... 2-11
2.5.2 Receiver Tuning of CLOVER-II Signals.....................2-12
2.5.3 Transmit Modulation ..................................................2-12
2.5.4 Receiver
AGC and Noise Limiter...............................2-12
2.5.5 Receiver Filters ..........................................................2-12
2.5.6 Receiver Audio Level .................................................2-13
2.5.7 Adaptive Control
and Radios .....................................2-13
Operation Under Windows
3.1
3.2
3.3
3.4
3.5
3.6
Installing DXPWin Software...................................................... 3-1
3.1.1 The DXPWin Setup Window........................................ 3-2
3.1.2 Changing DXPWin Directory........................................ 3-2
3.1.3 Beginning Installation................................................... 3-2
Manual Conventions .................................................................3-2
Running DXPWin ......................................................................3-4
MY CALL Setup .........................................................................3-4
Main Screen ..............................................................................3-4
Menu Line .................................................................................3-5
3.6.1 File Menu .....................................................................3-5
3.6.2 Edit Menu .....................................................................3-5
3.6.3 View Menu ...................................................................3-6
3.6.4 Options Menu...............................................................3-6
3.6.5 Special Menu ...............................................................3-7
DXP38 MANUAL
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Chapter 4
HAL990308
3.7 Toolbar .....................................................................................3-7
3.8 Receive (RX) Buffer..................................................................3-9
3.9 Echo on Transmit (TX) Buffer...................................................3-9
3.1 0 Transmit Buffer..........................................................................3-9
3.11 Tuning Indicators.......................................................................3-9
3.12 Status Bar ...............................................................................3-10
3.13 General Configuration.............................................................
3-1 0
3.14 Operating RTTY......................................................................
3-11
3.14.1 RTTY Codes .............................................................. 3-11
3.14.2 Starting RTTY ............................................................ 3-11
3.14.3 RTTY Data Rates....................................................... 3-11
3.14.4 Control Options .......................................................... 3-11
3.14.5 Configuration Options ................................................3-12
3.14.6 Special
RTTY Transmit Keys .....................................3-13
3.15 Operating
CLOVER-11 .............................................................3-14
3.15.1 Tuning a CLOVER Signal ..........................................3-14
3.15.2 RX/TX Status Table ...................................................3-15
3.15.3 Adaptive
ARQ Mode ..................................................3-15
3.15.4
FEC Mode ..................................................................3-16
3.15.5 Listen Mode................................................................3-17
3.15.6 TestMode..................................................................3-17
3.15. 7 CLOVER-II Configuration Menu Parameters.............3-17
3.16 Operating AMTOR ..................................................................3-18
3.16.1 Control Options ..........................................................3-18
3.16.2
ARQ Mode .................................................................3-18
3.16.3
FEC Mode..................................................................3-20
3.16.4 Listen mode................................................................3-20
3.17 Operating P-Mode...................................................................3-20
3.17.1 ARQ Mode ................................................................. 3-21
3.17.2 FEC Mode (UNPROTO) ...........................................3-22
3.17.3 LISTEN Mode.............................................................3-23
Operation Under
DOS
4.1
4.2
4.3
4.4
4.5
4.6
4.7
4.8
Installing DXP38 Software ........................................................
4-1
Manual Conventions .................................................................4-2
MYCALL Setup .........................................................................4-3
Main Screen ..............................................................................4-3
4.3.1 Tuning Indicators .........................................................4-4
4.3.2 Receive (RX) Buffer.....................................................4-4
4.3.3 Status Line ...................................................................4-4
4.3.4 Command Line.............................................................4-4
4.3.5 Transmit (TX) Buffer ....................................................4-4
4.3.6 Information Line ...........................................................4-4
Configuration Screens ............................................................
4-11
Hot-Keys .................................................................................4-13
4.6.1 Function Hot-Keys .....................................................4-13
4.6.2 Alt-letter Hot-Keys......................................................4-13
File 0 perations........................................................................4-16
4.7.1 Load TX Buffer...........................................................4-16
4.7.2 Save
To Disk..............................................................4-16
4.7.3 Stop
Send I Save .......................................................4-17
4.7.4
Send From Disk .........................................................4-18
4.7.5 Directory.....................................................................4-18
4.7.6
Load DXP38...............................................................4-18
TX Buffer Editor......................................................................A-18
DXP38 MANUAL

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Chapter 5
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Chapter 6
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4.9 Operating RTTY......................................................................4-19
4.9.1 RTTY Codes ..............................................................4-19
4.9.2 Starting RTTY ............................................................4-19
4.9.3 RTTY Data Rates......................................................
A-20
4.9.4 Control Menu Options ................................................4-20
4.9.5 Configuration Menu Options ......................................4-22
4.9.6 Print Squelch..............................................................4-23
4.9.7 Special RTTY Transmit Keys.....................................4-23
4.10 Operating CLOVER-II .............................................................4-23
4.1 0.1 Tuning A CLOVER Signal..........................................4-24
4.10.2 RX!TX Status Table ...................................................4-25
4.10.3 Adaptive ARQ Mode ..................................................4-26
4.1 0.4 FEC Mode..................................................................4-27
4.10.5 LISTEN Mode.............................................................4-28
4.10.6 Test Mode ..................................................................4-28
4.1 0. 7 CLOVER-II Configuration Menu Parameters.............4-29
4.11 Operating AMTOR ..................................................................4-29
4.11.1 ARQ Mode .................................................................4-29
4.11.2 FEC Mode..................................................................4-33
4.11.3 LISTEN Mode.............................................................4-33
4.12 Operating P-Mode...................................................................4-33
4.11.1 ARQ Mode .................................................................4-33
4.11.2 FEC Mode
(UN PROTO) ............................................4-35
4.12.3 LISTEN Mode.............................................................4-36
In Case Of Difficulty
5.1
5.2
5.3
5.4
5.5
5.6
5.7
User Adjustments and Alignment..............................................
5-1
DXP Hardware Problems.......................................................... 5-1
Software Problems....................................................................5-2
Operational Problems ...............................................................5-2
User Service..............................................................................5-3
User Information........................................................................5-3
Returning Equipment to Factory for Repair ..............................5-4
Specifications
Warranty
DXP38 MANUAL
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HAL990308
Table 2.1
Table 2.2
Table 2.3
Table 2.4
Table 2.5
Table 2.6
Table 2.7
Table 3.1
Table 3.2
Table 3.3
Table 3.4
Table 4.1
Table 4.2
Table 4.3
Table 4.4
Table 4.5
Table 4.6
Table 4.7
Table 5.1
Figure 2.1
Figure 2.2
Figure 2.3
Figure 2.4
Figure 2.5
Figure
4.1
Figure 4.2
Figure 4.3
Figure 4.4
Figure 4.5
Figure 4.6
Figure 4.7
Figure 4.8
Figure 4.9
Figure 4.10
Tables
DXP38 1/0 Connections...............................................2-2
AF OUTVoltage Ranges .............................................2-4
DXP38 FSK Output Options ........................................2-5
FSK for Typical Amateur Transceivers ........................2-5
RS-232 Data 1/0 Connections .....................................2-7
DXP38 Status lndicators..............................................2-9
CLOVER-II HF Radio Requirements .........................2-11
RTTY Data Rates and Speeds .................................. 3-11
RTTY and AMTOR Default Settings..........................3-12
Baudot Code Differences...........................................3-13
Special RTTY Transmit Keys.....................................3-14
Function HOT-KEY Assignments...............................4-14
Alt-letter HOT-KEY Assignments...............................4-15
Transmit Buffer Edit Keys ..........................................4-19
RTTY Data Rates and Speeds ..................................4-20
RTTY Control Options................................................4-20
Baudot Code Differences...........................................4-22
Special RTTY Transmit Keys.....................................4-23
User-Set Options..........................................................
5-1
Figures
DXP38 Rear Panel Connectors...................................2-2
Radio System Connections..........................................2-3
Jumper J3 and J6.........................................................2-4
Typical M/S Mode Tuning Display .............................2-10
Typical M Mode Tuning Display.................................2-10
DXP38.EXE Main Screen ............................................4-3
Main Menu Tree for CLOVER (left side)......................4-5
Main Menu Tree for ALL Codes (right side).................4-6
Main Menu Tree for Baudot RTTY (left side)...............4-7
Main Menu Tree for ASCII RTTY (left side).................4-8
Main Menu Tree for AMTOR (left side)........................4-9
Main Menu Tree for P-Mode (left side) ......................4-10
Configuration Menu- Page 1 (CLOVER &System) ..4-12
Configuration
Menu- Page 2 (HERE IS &HISCALL)4-12
Configuration
Menu- Page 3 (FSK Modes)...............4-13
DXP38 MANUAL

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FCC Statement
FCC RADIO FREQUENCY EMISSIONS STATEMENT
(Reference: CFR 47, Part 15)
U.S. Federal Communications Commission (FCC) Rules and Regulations, CFR47, Part
15,
require inclusion of the following text in this manual.
INFORMATION TO THE USER (Section 15.105)
NOTE: This equipment has been tested and found to comply with the limits for a Class B digital
device, pursuant to Part 15
of the FCC Rules. These limits are designed to provide reasonable
protection against harmful interference
in a residential installation. This equipment generates,
uses and can radiate radio frequency energy and,
if not installed and used in accordance with the
instructions, may cause harmful interference to radio communications. However, there
is no
guarantee that the interference will not occur
in a particular installation. If this equipment does
cause harmful interference to radio or television reception, which can be determined by turning
the equipment off and
on, the user is encouraged to try to correct the interference by one or more
of the following measures:
--Reorient or relocate the receiving antenna
--Increase the separation between the equipment and the receiver.
--Connect the equipment into
an outlet on a circuit different from that to which the receiver is
connected.
--Consult the dealer or experienced Radio/TV technician for help.
INFORMATION TO USER (Section 15.21)
The user is cautioned that any changes or modifications not expressly approved by the party
responsible for compliance could void the user's authority to operate the equipment.
P-Mode
The word "P-Mode" is the HAL designation for a communications protocol that may also be known as "Pactor", a
registered trademark of the Spezielle Communications Systeme GmbH (SCS) firm in Hanau, Germany. HAL affirms that,
to the best of its knowledge, "P-Mode" is compatible and interoperable with the protocol SCS calls "Pactor'' and with the
link establishment mode of the protocol SCS calls "Pactor-11" .
HAL990308 DXP38 MANUAL

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Chapter 1
Introduction
1.1 The DXP38 Manual
The DXP38 is the latest
in the evolution of HAL DSP modem products that started with the PCI-4000.
Operation, software, and control are very similar to that
of the PCI-4000, P38, and DSP-41 00 modems.
Many
of the same terminal programs used with these modems may also be used with the DXP38 with little
or no changes. If you are already familiar with use of HAL DSP modems, please have a look at the
instructions and diagrams
of Chapter 2 and then jump right in.
Unlike previous HAL DSP modems, the DXP38 includes a hardware front panel tuning indicator that works
with all terminal programs. The crossed-bar display is used for all data modes -RTTY, AMTOR, P-Mode,
and CLOVER. The display may be switched between the normal MIS "+" tuning display and a zero-center
tuning error scale. Use of the display for each mode is discussed in Chapter 2.
The DXP38 also includes DXPWin, a new HAL terminal program that runs under W95, W98, or NT4.0
Windows™ operating systems. The display format of DXPWin is very similar to the format of our DOS-
based P38.EXE, PCC.EXE, and DSP41.EXE programs. You may not need much instruction to use this
software, particularly ifyou are familiar with windows programs and ifyou have previously used the HAL
DOS programs. However, a thorough reading
of Chapter 3 is in order after "the new wears off'.
Our DOS-based terminal program, DXP38.EXE, is also included for all that wish to continue using PC-
DOS. This is the popular and proven program HAL has included with all of our DSP modem products
since 1993. Chapter 4 includes all of the operating details for those who may not have used this software
or those of us who have forgotten a detail or two.
If you have problems, read Chapter 5, In Case of Difficulty. Sometimes, fixing a problem can be as simple
as adding shielded wire; sometimes you need to send the modem to us for "heart surgery" or maybe it's
time for an "oil change and a lube job"!
Chapter 6 lists all
of the fine-print specifications for those who like impressive numbers.
Be sure to read the Warranty. It is the standard HAL Warranty we have used for years. HAL stands behind
its products. If you have a problem -LET US KNOW!
1.2 DXP38 Software
Your DXP38 package includes four (4) 3.5" diskettes. Three of these diskettes contain DXPWin, the
windows-based terminal program. The remaining diskette contains DXP38.EXE, the DOS-based terminal
program, and firmware that is used by the on-board microprocessors. Loading of DXPWin is discussed in
Chapter 3 and loading of DXP38.EXE in Chapter 4. The firmware files on disk 4 will not be required unless
the contents of the flash memory become damaged. Consult Chapter 5 to determine when reloading is
necessary and how to reload the firmware.
HAL990308 DXP38 Manual

CHAPTER 1 INTRODUCTION 1-2
1.2.1 Minimum Requirements
The DXP38 modem and its DXPWin or DXP38.EXE Software may be used with virtually any RS-232-
equiped, IBM-compatible personal computer (PC). The serial port requirements are:
Connector (DXP38): DE9P (male pins)
Data Format:
Data Rate: RS-232 levels with RTS/CTS hardware flow control
9600 baud
Data Format: No Parity, 8 bit data, 1 Stop bit (N-8-1)
The requirement on the PC itself is dependent upon whether the DOS or windows version of terminal
software is used. Relatively old, slow, and inexpensive PC's may be used with DOS software; use of
Windows requires a modern, fast, and relatively expensive PC. The minimum recommendations are:
DXPWin (use with Windows-95™, Windows-98™, or Windows-NT4.0™):
PC-Pentium, 100 MHz
32MB RAM
1 - 3.5" floppy disk drive
1 - hard disk drive (20MB free space minimum)
VGA video card and monitor minimum
DXP38.EXE (use with PC-DOS):
PC-AT or higherwith MS-DOS or PC-DOS
IBM-compatible ROM BIOS
640K RAM minimum
1 - 3.5" floppy disk drive
1 -hard disk drive (1MB free space minimum)
Third-Party Programs: If you will be using "Third-Party" terminal programs with the DXP38 (software not
written by HAL), carefully read the documentation provided with the program and follow its instructions.
Note that the DXP38 uses the same command set as the DSP-4100 modem. If "DXP38" is not listed as a
modem option, try using "DSP4100" instructions. HAL Communications Corp. continues to work closely
with a number of software authors and firms to provide additional user software. See our web page for
links and a current list of "3rd Party" authors for CLOVER and DXP38 software.
1.2.2 Software and Documentation Up-Date
New versions of each program are available to all DXP38 owners as they are released by HAL
Communications. Some software changes may also require changes to the documentation (manuals).
Current copies of DXP38 software and documentation updates may be downloaded from our Internet web
page at www.halcomm.com.
If you have problems or need additional information, please call:
Customer Service Manager
Voice:
FAX:
HAL990308
[phone] (SAM- 5PM CST/CDT; Monday- Friday)
[phone] (24 hours/day)
DXP38 MANUAL

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Chapter 2
Installation and Set-up
This chapter discusses how to connect the DXP38 modem to the radio system and to a PC terminal.
Operation
of the front panel tuning and status indications is discussed in section 2.4. Installation and use
of HAL terminal software is presented in Chapter 3 (DXPWin for use with W95, W98, or NT4.0) or
Chapter 4 (DXP38.EXE for operation under MS-DOS).
2.1 Unpacking and Inspection
The DXP38 system includes the following materials:
1
-900-13800 Complete DXP38 product
This includes:
1
-910-13800 DXP38 HF Modem
1
-870-13800 DXP38 MANUAL
1 - 865-13810 DXP38-Disk
#1 (DXPWin #1, Rev X)
1
-865-13820 DXP38-Disk #2 (DXPWin #2, Rev X)
1 - 865-13830 DXP38-Disk #3 (DXPWin #3, Rev X)
1
-865-13840 DXP38-Disk #4 (DXP38.EXE, DXP38.LOD &DXP38.S28, Rev x)
1
-310-16032 DC Power Connector
When opening the DXP38 shipping carton, carefully inspect it for any evidence
of shipping damage. Any
damage should be immediately reported to your shipping carrier. Be sure to save any damaged packing
materials. Note that a damage claim must be filed by you with the shipping carrier -
NOT HAL
Communications. HAL will be glad to assist in such cases, but only the shipping carrier can pay claims.
Check to be sure that all
of the materials listed above are contained in your DXP38 package. If you find
any materials missing, please contact your dealer or HAL Communications as soon as possible.
HAL990308 DXP38 MANUAL

CHAPTER 2 INSTALLATION 2-2
2.2 DXP38 Rear Panel Connections
The rear panel
of the DXP38 modem is shown in Figure 2.1 and the limits for each 1/0 signal are shown
in Table 2.1. These requirements are compatible with all modern amateur transmitters and receivers. DO
NOT EXCEED THESE LIMITATIONS.
GND
©
DC
HAL CoMMUnico. tions Corp.
DXP38 DSP ModeM
Serio.l
No. -------
MQde In USA
AF AF
PTT
OUT TX IN RS-232
LVL
IN SELCAL FSK
0 @ @ @
@®@ o\i l]o
Figure 2.1 DXP38 Rear Panel Connections
Table 2.1
DXP38 1/0 Connections
CONN FUNCTION 1/0 LIMITS
AFIN Audio from RX Input 5V p-p
AFOUT Audio to TX Output -30d8m (25 mV)
PIT
Push-to-Talk Output Output +50V@ 100 rna
FSK FSK Output Output
+50V@ 100 rna
SELCAL SEL-CAL Output Output
+50V@ 100 rna
DC IN DC Power Input Input
+9- +18V@ 0.6A
GND RF Ground Ground
RS-232 Data
110 +/-15 VDC
Typical connections
of the DXP38 to radio station equipment are shown in Figure 2.2.
2.2.1 Audio Input
The DXP38 Audio Input (AF IN) is unbalanced. The Input impedance is 10,000 ohms, ±10%. This input
can be directly connected to a wide variety
of receiver audio output terminals including low-impedance
speaker
(4- 16 ohms), line (600 ohms), headphone (2K ohms) or "recorder output" (10,000 ohms). A
matched terminating resistor is not required. The maximum audio input voltage to the DXP38 should not
exceed 5 volts peak-to-peak (1.7V rms; +7 dBm). The DXPWin and DXP38.EXE terminal programs
include tuning indicator bars which may be used to adjust the receiver output volume.
HAL981211 DXP38 MANUAL

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CHAPTER 2 INSTALLATION
GND
0
DC
IN
0
ANTENNA (V
HAL COI'I.,unleo. tlons Corp. HF
TRANSCEIVER
DXP38 DSP Model'l
Serlo.l No.
_ ......
RX TX STOP
AF SCAN . AF
Ar
AF
OUT IN
PTT
FSK
<OPT)
GND
ELCAL FSK
PTT
llUT L'C\_ IN RS-232
@ @ @ @®@ o\liiilo
@ @ @ @ @
90
lJ 6 t
~;~;I
r~~
lJ
0
lJ
9
AF PTT FSK
I
OUT
I
I
~
I I
I I
r-,
I
II
I © I
L--------~--------------GL!J-
I
DC
+ PO'w'ER
I
SUPPLY
I -
9-lBV
0.6A
~rl~
RS-232
Serlo.l liD
COMM Port
PC
Co.blnet
Co.se
<Ground)
Figure 2.2 Radio System Connections
I
(
(
I
2-3
SCAN
ONTROLLER
<OPTIONAL>
HAL981211 DXP38 MANUAL

CHAPTER 2 INSTALLATION 2-4
2.2.2 Audio Output
The DXP38 Audio Output (AF OUT) is also unbalanced. The nominal output impedance is 600 ohms but
AF OUT does not require a termination load. It may be connected to a wide variety
of transmitter audio
input terminals including microphone (low or high-impedance), "phone patch", or "line (600 ohm). The AF
OUT circuit includes a 1uF series capacitor to prevent DC loading
of transmitter microphone inputs that
have a DC bias voltage.
Jumper J3 on the circuit board (see Figure 2.3) sets two output voltage ranges. The exact level may
be
set via the rear panel TX LVL adjustment. The output ranges are shown in Table 2.2.
J3
Open
Closed
Figure 2.3 Jumper J3 and J6
Table 2.2
AF OUT Voltage Ranges
Nominal Output Voltage Adjustment Range
-30 dBm (25 mV rms) -50 to -20 dBm (2.5 to 78 mV rms)
-10 dBm (250 mV rms) -30 to -10 dBm (25 to 250 mv rms)
All DXP38 units are shipped with jumper J3
in the -30 dBm position and the rear panel output control set
for -30 dBm. This output voltage will
be correct for use with microphone (or "phone patch") inputs of most
HF SSB transmitters. J3 should be changed to the "Closed" position when the DXP38 is connected to
transmitters that require a high-level transmit audio input. Proper adjustment
of the TX LVL control is
discussed in section 2.3.
IMPORTANT CONSIDERATION WHEN USING CLOVER: The DXP38 has an "FSK Output" that may be
used for AMTOR, P-Mode and RTTY. However, the CLOVER-II waveform cannot be generated when
transmitters are operated
in an "FSK" mode. The transmitter should be operated in LSB mode and the
CLOVER-II transmit audio tone signal must
be connected to the transmitter audio input.
2.2.3 PTT Output
The DXP38 provides TX/RX control of the radio equipment via the PTT (Push-To-Talk) transistor output
on the rear panel. This is shorted to ground to transmit and is open circuit when receiving. The TX/RX
PTT circuit should have a positive polarity with a maximum open-circuit voltage (RX state)
of 50 volts DC
and a maximum closed circuit current (TX state)
of 100 rna DC.
HAL981211 DXP38 MANUAL

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CHAPTER 2 INSTALLATION 2-5
2.2.4 FSK Output
FSK OPTION SELECTION: The DXP38 FSK output circuit may be used with many modern HF
transceivers that include an FSK input to transmit RTTY, AMTOR, or P-Mode. However, as previously
noted, CLOVER cannot be transmitted using the transceiver FSK input. A "universal" FSK interface
standard for HF transmitters does not exist between manufacturers or between models made by the
same manufacturer. Four FSK interface options may be selected that support those FSK standards we
have encountered. If you have additional information regarding FSK inputs, we would appreciate your
comments.
The FSK output is an NPN transistor which can be set for open collector (O.C.) or pulled up to+ 5 Volts
D.C. (+5V) by setting jumper plug J6 (see Figure 2.3). The factory default setting is to O.C. (Open
Collector). The polarity of the FSK output is selected from the operating program (DXPWin or
DXP38.EXE). See Chapters 3 and 4 to access this parameter on the Configuration menu. The factory
default setting is to Normal polarity.
Some transceivers require a switch to ground
on the FSK input. In this case, use the O.C. (Open
Collector) setting for J6. Other transceivers require a voltage
on the FSK line. In this case, use the +5V
setting for J6. Table 2.3 summarizes the four possible combinations of DXP38 FSK output signal. Table
2.4 lists the correct FSK combinations for a few transceivers.
HAL981211
POLARITY
NORM
REV
NORM
REV
MFGR
TEN-TEC
TEN-TEC
TEN-TEC
KENWOOD
KENWOOD
KENWOOD
KENWOOD
ICOM
ICOM
ICOM
ICOM
ICOM
ICOM
YAESU
YAESU
YAESU
YAESU
YAESU
Table 2.3
DXP38 FSK Output Options
J6
O.C.
O.C.
+ 5V
+ 5V
MARK
ov
Floating
ov
+ 5V
Table 2.4
FSK for Typical Amateur Transceivers
MODEL POLARITY
CORSAIR NORM
PARAGON (585) NORM
OMNI (582) NORM
TS-180 NORM
TS-440 NORM
TS-930s REV
TS-940s NORM
IC-730 REV
IC-740 REV
IC-745 REV
IC-751 REV
IC-761 REV
IC-781 REV
FT-101ZD NORM
FT-107 NORM
FT-910/902 NORM
FT-980 NORM
FT-ONE NORM
SPACE
Floating
ov
+5V
ov
J6
+5V
+5V
+5V
O.C.
+5V
O.C.
O.C.
O.C.
O.C.
O.C.
O.C.
O.C.
O.C.
O.C.
O.C.
O.C.
O.C.
O.C.
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DXP38 MANUAL

CHAPTER 2 INSTALLATION 2-6
This data is based on reports from HAL customers and some manufacturers. HAL would like to know of
any other information you may have concerning FSK inputs. A careful reading ofyour transceiver manual
or a call to the manufacturer's "Customer Assistance Department" may be required to determine which
interface level is required for your equipment.
If your transceiver is not listed or you have some doubts
about the required level or polarity, try the following:
1. Start with NORM polarity and set to J6 O.C. (factory default settings).
2. Try sending simple FSK RTTY to a friend with a working RTTY station.
3. If you cannot send Mark/Space RTTY, the J6 setting may be wrong. Try setting J6 to +5 V.
4. Ifyou can send FSK, but it is upside down, change the polarity to REV.
Note: This information
is offered as a service to our amateur customers only. HAL cannot guarantee
performance for FSK mode nor be held responsible for any damage that may result from connection of
voltages to a transceiver "FSK" input jack. If you have any doubts, please contact the transceiver
manufacturer before making any connections.
2.2.5 SEL-CAL Output
The SEL-CAL output of the DXP38 is an open-collector NPN transistor (MPS-A42) that switches to
ground during
an ARQ link. This signal may be used to signal that the station has been called and linked
in ARQ mode or to control frequency scanning radio systems. The rating of the switching transistor is +50
VDC maximum (open circuit) and 100
rna DC maximum (closed circuit).
The SEL-CAL output
is normally open ("high") until the call sign of the local station (MYCALL) is
recognized during an ARQ link request. When MYCALL is recognized, the SEL-CAL output shorts to
ground ("low"). Options
in DXPWin and DXP38.EXE allow selection of two modes to match switching
requirements ofvarious radio models. The modes are "CONTinuous" and "PULSE".
In the CONTinuous SEL-CAL mode, the SEL-CAL output signal remains in the "low" state throughout the
ARQ link. The signal will revert to "high" when the ARQ link
is terminated at disconnect.
In the PULSE SEL-CAL mode, the SEL-CAL output signal will pulse "low" for 2 seconds when MYCALL is
recognized, remains "high" during the ARQ link, and will again pulse "low" for 2 seconds when the ARQ
link is broken (disconnected).
The interface wiring to the SEL-CAL output varies widely with radio manufacturer and model. Detailed
connection information should
be obtained from either the radio manufacturer or from other radio
operators who have made successful scan-control interfaces to their radios. At this writing, none of the
commercially available amateur radio transceivers provide a rear-panel scan-control input connection -all
makes and models require modification.
While HAL warrants the operation of the SEL-CAL output signal
to be as described above, this warranty
does not extend to the functionality of use of the SEL-CAL signal with other equipment. Further, HAL
must disclaim any damage to the radio equipment or
to the DXP38 which may result as a consequence of
user modification of his radio equipment.
2.2.6 RS-232 Connections
All data connections to your computer terminal are made via the 9-pin RS-232 connector. These
connections follow industry standards and pre-manufactured cables may be used to connect between the
PC's serial 1/0 port and the DXP38. If you are writing your own software for the DXP38, please contact
HAL and request a copy of HAL Engineering Documents
E2001 and E2005.The signal connections are
described
in Table 2.5.
HAL981211 DXP38 MANUAL

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CHAPTER 2 INSTALLATION 2-7
Table 2.5
RS-232 Data 1/0 Connections
PIN
LABEL SIGNAL OPERATION
1 DCD Data Carrier Detect High = Signal detected
2 RXD Receive Data Demodulated receive data
3 TXD Transmit Data Data to
be transmitted
4 DTR Data Terminal Ready
High= PC is ready
5 GND Ground Ground
6 DSR Data Set Ready High = DXP38
is ON
7 RTS Request To Send High = RXD Flow Control
8 CTS Clear To Send
High= TXD Flow Control
9 N.C.
no connection
2.2.7 Ground Connection
It is very important that low-resistance RF ground connections be made between all units of the radio
transmit I receive station. Otherwise, transmitter
RF interference (RFI) may severely limit operation of the
PC or the DXP38 modem. Similarly, high-frequency noise from the computer or modem may cause
severe interference when receiving. Ground connections should
be short and have low resistance and
low inductance. Shield braid that
is at least ~" wide is recommend for all RF ground connections.
2.2.8 DC Power Connection
The DXP38 may be operated from any DC power source that is filtered (free of hum and noise) and
relatively stable (short-term voltage fluctuations less than
:t_1 0%). The voltage output of the power source
should be between 9 to 18 VDC. Note that the positive terminal connects to the center
pin. The DXP38
requires approximately 250
rna during normal operations, but reloading the flash memory requires
approximately 500
rna. Be sure to use the DC power connector supplied with the DXP38 or obtain an
exact copy. There are many versions of the coaxial power plug offered for sale and most "look similar"
but may not be reliable. Contact HAL ifyou need a new or an additional power connector.
2.3 Initial Transmitter and Receiver Adjustment
The following procedure describes how to test the DXP38 with your radio equipment and make initial
adjustments. The set-up and test procedures used with DXP38.EXE are described below but you may
also wish to review your desired program
in more detail (Chapters 3 and 4).
These adjustments take advantage of the "Test Mode" of CLOVER but the settings obtained apply to all
modes- RTTY, AMTOR, P-Mode, and CLOVER.
1. Connect the DXP38 AF IN, AF OUT, and PTT to the HF Radio Equipment. Disconnect the
microphone
and any other transmitter audio inputs.
2. Connect the DXP38 RS232 connector to the PC's serial 110 connector.
3. Set the receiver and transmitter controls as follows:
a. BAND = convenient "RTTY frequency"
b. Mode= LSB
c. RX AF OUT = 25% of maximum
d. RX FILTER = "Voice"
e. RF OUT = dummy load
f. TX AF IN (MIC GAIN) = minimum
g. TX RF OUT= minimum
HAL981211 DXP38 MANUAL

CHAPTER 2 INSTALLATION 2-8
h. TX ALC and COMPRESSION = OFF
i. TXVOX= OFF
j. RIT I XIT = OFF
k. Antenna = dummy load
4. Load DXPWin or DXP38 (see Chapter 3 or 4)
5. Turn PC power ON and let it boot.
6. Select CLOVER mode.
7. Turn Transceiver AC power ON.
8. Adjust RX AF GAIN control until amplitude bars show movement on noise.
9. Enter TX TEST mode.
10. Type the [Space bar] to set single-tone test and turn the transmitter ON.
11. Slowly increase the MIC GAIN control (and TX RF OUT control if necessary) until the desired full RF
output power is obtained. Watch the ALC meter and/or light; set the RF Output to just belowthe level
at which ALC control starts.
DO NOT CHANGE THIS MIC GAIN SETTING. See step 15 if the MIC
GAIN control must
be set at the extreme low end of its range (near counter-clockwise end).
12. Switch the transceiver meter to read RF output and note the reading. This is the peak power output of
your transmitter when using CLOVER-II.
13. Type the [Space bar] again to enable four-tone test mode. Note the new reading of the RF Output
meter. This is the average power output ofyour transmitter.
14. Type [Space bar] once again to turn the transmitter OFF. Type [Ait]-0 or [Esc] to exit TEST mode.
The difference
in RF output measured in steps 12 and 13 varies greatly with the make and model of
the transceiver and the design ofthe Wattmeter circuit. Some meters may show no difference; others
may show as much as a
4:1 (6 dB) difference. The exact meter readings are not critical. However, it
is very important that the adjustment
in step 11 sets the maximum non-ALC controlled power output
level ofthe transmitter.
IMPORTANT: Do not increase the transmitter microphone gain control setting beyond that set in step
11. While this might cause the RF output meter to read higher output power, it will also assure that
your transmitted CLOVER signal is distorted and degrades system performance. Over-driving may
also results
in wide-bandwidth "splatter''.
15. The DXP38 transmit audio output level may be adjusted with the screwdriver set TX LVL control on
the rear panel. This control is set at the factory to its maximum output position. If the setting of the
MIC GAIN control determined
in step 10 is very low (near the CCW end), set the DXP38 rear panel
control to the middle of its range and then repeat steps
10 through 14. This will reduce the output
from the DXP38 and increase the setting of the transmitter's MIC GAIN control. Use the highest
setting
of the DXP38 control that produces a usable setting of the transmitter's MIC GAIN control to
minimize "hum" and noise on the modulation.
16. Some transceiver models (IC-735 and possibly others) include a rear panel transmit audio input but
that its level
is not adjustable by the front panel MIC GAIN control. If this input is used, transmitter
HAL981211 DXP38 MANUAL

• CHAPTER 2 INSTALLATION 2-9
power level adjustments must
be made using the DXP38 rear panel control as noted in #15. It may be
simpler to connect directly to the front panel microphone jack ofthese transceivers.
2.4 Front Panel Status and Tuning Indicators
2.4.1 Status Indicators
The vertical line of six LED's on the DXP38 front panel shows the modem status. Their function is
described
in Table 2.6.
LABEL
RX
TX
ERR
LINK
CALL
STBY
Table 2.6
DXP38 Status Indicators
DESCRIPTION
On when receiving.
Flashes
in ARQ modes when linked.
On when transmitting.
Flashes
in ARQ modes when linked.
On when Errors are detected in ARA modes.
On when linked in ARQ modes
On when calling in ARQ modes
On when in standby in ARQ modes
In any mode condition, one of the six LED's will be on if power is turned on.
e 2.4.2 Tuning Indicator- MIS Mode
t
The DXP38 uses a crossed-line LED bar display to aid when tuning the receiver. This display may be set
to two different tuning modes
by the front panel M/S and M switch. When the "M/S" display mode is set,
the tuning bar functions much like the familiar crossed-ellipse oscilloscope display.
In FSK modes (RTTY,
AMTOR, and P-Mode), the horizontal bar shows the signal amplitude from the "Mark" filter and the
vertical bar shows the "Space" amplitude. Correct FSK mode tuning is achieved when both bars show
maximum length.
The M/S mode also shows filter amplitudes when tuning CLOVER but each bar segment now shows the
amplitude
in the four CLOVER tone filters. Optimum tuning is indicated when all four bars have maximum
length from the center out. Note that CLOVER tuning data
is updated only every 2 seconds. Receiver
tuning adjustments must therefore be made very slowly and gently! Typical tuning displays for M/S mode
for FSK and CLOVER modulations are shown
in Figure 2.4.
2.4.3 Tuning Indicator- M Mode
The tuning display may also be used to determine the exact tuning error when rece1v1ng FSK and
CLOVER modulation.
In this case, the horizontal bar becomes a zero-center frequency error display.
Each horizontal bar segment ("dot") corresponds
to a tuning error of approximately 5 Hz, providing a
tuning indicator range of
:!:50 Hz. Deflection of a dot to the left of center indicates a negative tuning errors
(below correct frequency), to the right a positive tuning error (signal tuned too high). The vertical bar is
used to emphasize fine-tuning with a total range of just :!:20Hz from no display to full scale. The vertical
display shows a continuous bar that increases in length as correct tuning is approached. When the signal
is tuned exactly to match the DXP38 receive filters, the center
LED and all of the vertical LED bar
segments are turned
on. The frequency tuning mode is slower to respond than when the MIS mode is
used. Tune slowly and pause a second or two between each receiver adjustment. Tuning conditions for
M mode are shown in Figure 2.5.
HAL981211 DXP38 MANUAL

CHAPTER 2 INSTALLATION 2-10
Print
~I
Squelch
~I
/ "
Pl"lnt Pl"lnt
Dff Dn
MARK
..
/ \.
MARK
MARK
~
•
MARK
~~
Very Low A
Little Low Correct A Little High Very
High
RTTY,
AMTDR, P-Mode
Tone 12..,
Tone 14
Tone 14
Very Low A
Little Low
Correct A Little High Very High
CLOVER-II
Figure 2.4 Typical M/S Mode Tuning Display
Fc-50 Hz Fc-30 Hz Fc-20 Hz
Fc-15 Hz
Fc-10 Hz
Fc-5 Hz
Fc±O Hz Fc+lO Hz
Fc+20 Hz
Fc+50 Hz
Figure 2.5 Typical M Mode Tuning Display
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CHAPTER 2 INSTALLATION 2-11
2.4.4 Print Squelch Indicator
In Baudot and ASCII RTTY modes and when the tuning indicator is set to show "MIS", the center LED of
the "X" shows RTTY Print Squelch condition. This center LED will
be ON when the signal exceeds the
print squelch threshold and receive signals can be "printed" (displayed
on the PC screen). This LED will
also be turned
ON when the Print Squelch feature is turned OFF as all signals and noise are passed to
the
PC in this case. Print Squelch status is shown only for Baudot and ASCII RTTY and only when the
tuning indicator is set to M/S mode.
2.5 Special Considerations When Operating CLOVER
The DXP38 and CLOVER-II waveform may be used with most HF SSB transmitters and receivers. HF
equipment used with the DXP38 and CLOVER-II should meet or exceed the requirements shown in Table
2.6. The more important radio parameters are discussed
in the following sections. Ifyou desire additional
information about CLOVER-II, request a copy of HAL Engineering Document E2006 and the latest
CLOVER Bibliography list.
2.5.1 Transmitter & Receiver Requirements
CLOVER-II waveform uses multiple tones and phase-shift modulation. Performance is best when the
transmitter and receiver frequencies match exactly. CLOVER will link and communicate when tuning
errors are as great as :!,30Hz. However, tuning should
be within :!,10Hz to obtain top performance at the
highest data rate modulation modes. Therefore, the radio equipment should be tunable
in at least 10 Hz
tuning increments and in finer increments if possible. Receivers whose frequency may be adjusted in 1.0
Hz increments are ideal for use with CLOVER.
It
is also very convenient if the transmitter and receiver frequency dials have 10 Hz or even 1 Hz
resolution. This is particularly true for network operation. Tuning aids such as the on-screen-tuning bars
are essential to obtain full performance from CLOVER. Dial calibration accuracy
is not essential for
proper CLOVER operation -but is very useful for reliable network operation.
The frequency stability of the transmitter and receiver should
be as high as possible. Frequency stability
within
:!,5 Hz per hour is desirable for manually controlled stations. Long-term stability of :!,1 0 Hz is
advised for automated network applications. The "High Stability" option offered for many transmitters,
receivers, and transceivers
is recommended for automated network stations.
HAL981211
TABLE 2.7
CLOVER-II HF RADIO REQUIREMENTS
PARAMETER
Tuning Increments
Frequency Stability
Frequency Accuracy
TX/RX Mode
Receiver Filter
TX/RX ON/OFF time
TX Audio Input
RX Audio Output
RX Output Impedance
Phase Linearity
TXALC
TX Compression
RXAGC
RX Noise Blanker
REQUIREMENTS
10Hz
:!,20 Hz/hr
:!,10Hz
LSB (not "FSK")
"Voice" bandwidth
32 ms
-10 dBm
to -30 dBm
Speaker or Line
10,000 ohms or less
Not Critical
OFF
OFF
SLOW (not Fast)
OFF or
min level required
DXP38 MANUAL

CHAPTER 2 INSTALLATION 2-12
2.5.2 Receiver Tuning of CLOVER-II Signals
The CLOVER-II signal is very unique and unlike any HF data signal previously used. The CLOVER-II
waveform is made
up of four tone pulses that are sent sequentially in time. The phase and amplitude of
each tone is changed when transmitting data. When tuned on a receiver, the CLOVER signal sounds
something like
an electronic telephone ringer ("bell"). We say CLOVER has a "twitter" sound.
Accurate tuning
of the received CLOVER signal is very important. Receiver tuning should be within :t30
Hz
of the correct frequency and with :t 10Hz for optimum operation. Receiver adjustment to these
tolerances requires
an accurate tuning indicator and generally cannot be done "by ear''.
CLOVER continually computes
an internal phase and frequency reference from the received signal and
uses these references to (
1) detect data, (2) measure and compensate for ionospheric variations, and (3)
compensate for tuning inaccuracy and frequency drift between the two stations. It requires approximately
2 seconds
of integration to obtain the necessary frequency and phase accuracy. Because of this required
integration time, it can be very destructive to adjust the receiver frequency once correct tuning has been
found and CLOVER demodulation has begun.
Therefore the following GOLDEN RULES should
be followed.
1. Tune slowly and accurately.
2. When correct tuning is achieved, get your hand offthe knob!
3. Keep your hands off the tuning knob (Lock the dial if necessary).
2.5.3 Transmit Modulation
CLOVER-II is a "J2" emission -it is an audio waveform that must be connected to the audio input of an
SSB transmitter. CLOVER does not use the "FSK" transmitter feature of some HF transceivers. Either
USB or LSB may
be used with CLOVER, but we recommend LSB to be compatible with conventions
used
by other HF data modes.
2.5.4 Receiver AGC and Noise Limiter
Receiver AGC (or AVC) may also cause a demodulation and distortion effect like that described for
transmitter ALC. However, receiver AGC also prevents overload ofthe receiver
by strong signals. In most
situations, it
is recommended that SLOW receiver AGC be used to receive CLOVER signals. However,
non-manned automated stations should always use AGC set to the SLOW mode.
Noise limiters and/or blankers should
be used as little as possible as they are also amplitude leveling
devices. A good noise blanker may be used in severe conditions, but it should be turned OFF as soon as
conditions permit.
2.5.5 Receiver Filters
The -50 dB bandwidth of the CLOVER-II spectra is 500 Hz. The audio center frequency is normally set to
2250 Hz, producing a -50 dB audio spectrum from 2000 to 2500 Hz. This spectra is similar to that
occupied
by "high-tone AFSK" RTTY/AMTOR signals. However, unlike RTTY/AMTOR modems, the
DXP38 uses very precise and "sharp-skirted" digital filters that match the transmitted CLOVER spectra.
In addition, the DXP38 uses a 14-bit AID (analog-to-digital) converter with a dynamic range of
approximately 80
dB. The DSP filters within the DXP38 are therefore optimized for CLOVER and will
generally be considerably better than those used
in the receiver. In most cases it is not necessary to use
a narrow
IF filter in the receiver. The standard 2.1 to 2.7 kHz wide "voice filter'' is quite adequate for
CLOVER reception.
HAL981211 DXP38 MANUAL