manualshive.com logo in svg

SCS PTC-IIIusb, User Manual

Share
Download
SCS PTC-IIIusb User Manual Download Page 168

11 PSK31 

 

157

Chapter 11 

11

 

PSK31 

11.1

 

General 

The PSK31 system developed by Peter Martinez, G3PLX, offers the RTTY enthusiast a 
modern variation to this by now somewhat old fashioned operating system. It has 
markedly reduced bandwidth requirements and a better resistance to interference. 
The operating technique is very similar to the normal operation of Baudot-RTTY, 
although a more sensitive fine-tuning is required compared to the older system, as a 
PSK31 signal requires a tuning accuracy of a few Hertz. 
Technically, the system is a differentially phase modulated, single carrier, with a Baud 
rate of 31.25 steps per second. In practice, DBPSK and DQPSK are employed, but with a 
heavy leaning towards DBPSK. DQPSK, despite the use of convolutional Coding (k = 5), 
has shown itself to be more prone to errors at very low SNR's compared to uncoded 
DBPSK. The waveform pulse of PSK31 is the "Raised Cosine in time" so that the 
DBPSK signal switches between two-tone (when only phase changes are taking place) 
and a plain single tone carrier. The bandwidth between the first null points of the 
spectrum is 62.5 Hz. A specialty of PSK31 is that it allows the entire ASCII character set, 
even the back space" character is included. 

11.2

 

Activation and use of the PSK31 terminal 

The command to activate the PSK31 mode is 

PSKTerm

 in the 

cmd:-

menu. Command 

parameters are not required, and will be ignored if given. After turning on the PSK31 
terminal, the PTC-IIIusb is in the receive condition. Various PSK31 relevant settings are 
at their default or previously set values. The 

Quit

 command closes the PSK31 terminal, 

and returns to the normal STBY condition. Text input may be carried out whilst in the 
receive condition, and is placed in the type-ahead buffer. (This can be deleted at any time 
with <Ctrl-X>. 

11.3

 

Carrier Frequencies 

The audio carrier frequency for receive and transmit are calculated using the settings for 
MARK-fre SPACE-frequency/2. If one has MARK=1400 Hz and SPACE=1200 
Hz, then the carrier frequency is 1300 Hz. A special command for the PSK31 AF-carrier 
frequency is thus not required. The transceiver connected to the PTC-IIIusb can operate 
with the same settings as for PACTOR or AMTOR etc. The PSK31 carrier, when 
correctly tuned, lies exactly in the middle of the IF filter pass band. When the squelch is 
open (Hot-key <Ctrl-F>), the PTC-IIIusb adjusts the receive carrier frequency slowly 
(max approx. 

±

1 Hz / 5 sec) automatically. to match that of the received signal. A manual 

drift correction is not required. Refer also to chapter Hot-keys NET operation. 

Summary of Contents for PTC-IIIusb

Page 1: ...SCS PTC IIIusb Data Transmission Technology on Shortwaves Manual for Version 4 1 Copyright 2012 SCS GmbH Co KG ...

Page 2: ...ully put together It is however still possible that errors have crept in If any errors are found we ask your forgiveness and request you send us a short note pointing them out Your SCS Team Manual rev A PACTOR is a registered trademark of SCS GmbH Co KG Hanau GERMANY ...

Page 3: ...t to the following two conditions 1 This device may not cause harmful interference and 2 this device must accept any interference received including interference that may cause undesired operation This device is exempt from these rules in any transportation vehicle including motor vehicle and aircraft as per Part 15 103 a Any changes or modifications to this equipment may void the users authority ...

Page 4: ...3 Installation 11 3 1 Power Supply 11 3 2 USB 11 3 3 Bluetooth 12 3 3 1 Bluetooth Installation 14 3 4 Rear side configuration switch 14 3 4 1 ON 14 3 4 2 BIOS 14 3 4 3 SPARE 15 3 5 Connections to the transceiver 15 3 5 1 Connection to ICOM transceivers 17 3 5 2 Connection to Kenwood transceivers 18 3 5 3 Connection to Yaesu transceivers 18 3 5 4 Amplitude Adjustment 19 3 6 Transceiver Remote Contr...

Page 5: ... 36 5 8 3 Operating the NAVTEX Processor 37 5 8 4 Notes about NAVTEX practice 37 5 8 5 AMTEX 38 5 9 GPS 38 5 9 1 Connecting the GPS receiver 38 5 9 2 GPS position request 39 5 10 APRS 39 5 11 Robust HF Packet 39 5 12 PACTOR Duplex and PACTOR data transparency 40 5 12 1 Application for PACTOR Duplex 41 5 12 2 How to avoid incompatibility 42 5 12 3 PACTOR data transparency 42 5 13 Audio Functions 43...

Page 6: ...CWSpeed 57 6 30 CWTerm 57 6 31 CWWeight 59 6 32 CYcle 59 6 33 DAte Remote 59 6 34 DD 60 6 35 DELete Remote 60 6 36 DIR Remote 60 6 37 Disconnect 61 6 38 EQualize 61 6 39 ESCchr 61 6 40 FAX 62 6 41 FEc 62 6 42 FSKAmpl 62 6 43 HCr 63 6 44 Help Remote 63 6 45 LFignore 63 6 46 LICENSE 64 6 47 LIN 64 6 48 LIst Remote 64 6 49 Listen 65 6 49 1 PACTOR 3 65 6 50 LOCk 65 6 51 LOg Remote 66 6 52 LOGIn Remote...

Page 7: ...imer 74 6 69 PDuplex 75 6 70 Phase Remote 75 6 71 POSition Remote 75 6 72 PSKAmpl 76 6 73 PSKTerm 77 6 74 PT 77 6 75 PTChn 77 6 76 Qrt Remote 77 6 77 QRTChr 78 6 78 Read Remote 78 6 79 RELOad 78 6 80 REMote 79 6 81 RESEt Remote 79 6 82 RESTart 79 6 83 RLe 80 6 84 Send Remote 80 6 85 SERBaud 80 6 86 SFile 80 6 87 SHow Remote 80 6 88 SPAce 81 6 89 SQuelch 81 6 90 STatus 82 6 91 SYStest 84 6 92 Term ...

Page 8: ...3 SSTV 103 8 3 FAX and SSTV with JVComm32 104 8 3 1 Specifications 104 8 3 2 Reference of databytes concerning the PTC 105 8 4 Fax menu commands 105 8 5 The PTC IIIusb as COMPARATOR MODEM 106 8 6 MODEM commands in detail 107 8 6 1 Amfax 107 8 6 2 Fmfax 107 8 6 3 Sstv 107 8 6 4 Jvfax 108 8 6 5 JVComm 109 8 6 6 FSK 109 8 6 7 Comparator 110 8 6 8 PTC IIIusb with 300 baud HF Packet 110 8 7 Transmissio...

Page 9: ... Packet 119 9 5 KISS 119 9 5 1 Activating KISS mode the commands KISS and K120 9 6 SMACK 120 9 7 SRP 120 9 8 Commands 121 9 8 1 Aprs 121 9 8 2 Baud 124 9 8 3 CBell 124 9 8 4 CHeck 124 9 8 5 CMsg 124 9 8 6 Connect 125 9 8 7 CONStamp 125 9 8 8 CONVerse 125 9 8 9 CStatus 125 9 8 10 CText 125 9 8 11 DIGIpeat 126 9 8 12 Disconnect 126 9 8 13 FRack 126 9 8 14 Help 126 9 8 15 JHOST 127 9 8 16 KISS 127 9 ...

Page 10: ...0 Hostmode 135 10 1 The PTC IIIusb hostmode 135 10 2 Modern Times 136 10 3 DAMA 137 10 4 Commands 137 10 4 1 C 137 10 4 2 D 137 10 4 3 F 138 10 4 4 G 138 10 4 5 I 138 10 4 6 JHOST 138 10 4 7 K 138 10 4 8 L 139 10 4 9 M 139 10 4 10 N 139 10 4 11 O 139 10 4 12 P 139 10 4 13 PR 140 10 4 14 PS 140 10 4 15 PT 140 10 4 16 T 140 10 4 17 U 140 10 4 18 V 141 10 4 19 W 141 10 4 20 Y 141 10 4 21 B 141 10 4 2...

Page 11: ...R protocol 151 10 9 4 SLAVE protocol 152 10 9 5 Stuffing errors or unexpected header sequences 152 10 9 6 Start of the CRC hostmode 153 10 9 7 Example source code for CCITT CRC16 HDLC 154 11 PSK31 157 11 1 General 157 11 2 Activation and use of the PSK31 terminal 157 11 3 Carrier Frequencies 157 11 4 Level Setting 158 11 5 Prompt and Status 158 11 6 Hot keys 158 11 7 Receiver Tuning 159 11 8 CW Id...

Page 12: ...tures 176 13 22 1 Direct Channel Selection for YAESU Transceivers 176 13 23 Channel attributes 176 13 23 1 Preamp switching at R S XK 2000 Transceiver 177 13 23 2 Timer Attributes 177 13 23 3 Hex Attribute 177 13 23 4 Level Attribute 178 13 24 TRX Control Channel on Hostmode 178 14 The Bootloader 179 14 1 Bootloader and Firmware 179 14 2 Activating the Bootloader 180 14 3 Bootloader commands 180 1...

Page 13: ... 185 15 3 1 General 185 15 3 2 The modulation system 186 15 3 3 Error control coding 188 15 3 4 Online data compression 190 15 4 PACTOR 2 in practice 191 15 4 1 General points 191 15 4 2 Speed and robustness 191 15 4 3 CQ calls and broadcasts 192 16 Accessories 193 17 Technical Data 195 18 Connector Pin out 197 19 Glossary 200 ...

Page 14: ... 3 3 Connections to the transceiver 5 PIN DIN 17 Figure 3 4 Transceiver remote control 21 Figure 3 5 ICOM plug 22 Figure 3 6 GPS connector 24 Figure 4 1 The PTC IIIusb front 25 Figure 5 1 GPS connector 38 Figure 15 1 Raised Cosine Pulse Sampling points marked X 187 Figure 15 2 PACTOR 2 spectrum and 300 Bd FSK 200 Hz Shift 187 ...

Page 15: ...M 22 Table 3 15 YAESU FT 890 990 23 Table 3 16 YAESU FT 757 23 Table 3 17 YAESU V24 23 Table 3 18 YAESU newer generation 23 Table 5 1 Command prompts 28 Table 5 2 Remote commands 31 Table 5 3 PACTOR mailbox commands 32 Table 5 4 Packet Radio mailbox commands 34 Table 5 5 NAVTEX message types 37 Table 5 6 AMTEX message types 38 Table 6 1 AMTOR and NAVTEX reception 48 Table 6 2 Conversion of German ...

Page 16: ... via an USB connection but from the viewpoint of the software it behaves similar to a normal serial equipment For that in the command description you will often find relations to the serial connection interface of the PTC IIIusb In this case not a physical serial link is meant but the virtual COM port created by the USB driver on your PC If signals of the serial connection is referred to then the ...

Page 17: ...program you use and your service provider The email client e g Airmail automatically does most of the configurations needed and lets you successfully transfer email at a fraction of knowledge which this book presents So don t feel bothered by the thickness of the book but have a look into the documentation of your email client which will provide a well tailored description of all you need for HF e...

Page 18: ... with this software Table 1 1 List of programs We are frequently asked What is the best program for the PTC IIIusb This question cannot be answered easily as it is similar to someone asking What is the best car or What is the best operating system It s a question of personal preference and depends on the application If HF email is your application for your PTC IIIusb it may not be necessary to stu...

Page 19: ...ional Firmware have been adapted to mobile and maritime applications They provide additional functions to ease the access to professional HF services e g email server The following overview shows the Professional Firmware features installed in the PTC IIIusb PACTOR 3 high speed data transfer protocol Hayes compatible command interpreter Hayes mode phone modem compatibility PACTOR IP Bridge direct ...

Page 20: ...use of the bandwidth Fully backwards compatible to existing PACTOR I II networks 1 6 2 PACTOR IP Bridge The PACTOR IP Bridge PIB is a new Network Integration Protocol developed by SCS The dominant protocols of the Internet like TCP IP as well as the Point to Point Protocol PPP which have become standard for establishment of links between Internet applications are combined with the PACTOR modes The...

Page 21: ... automatically observed for new files appearing These sub directories are each associated with a destination callsign and a frequency If a new file appears in one of these sub directories because another application has created it or copied it there EasyTransfer automatically establishes a connection to the station associated and transfers the file s to the destination After the task is done the c...

Page 22: ... the press the Send Update button which is enabled now You can see the progress bar on the screen of SCSupdate After the firmware is transferred completely the modem will install it automatically You can watch the progress of this procedure on the modems LEDs doing some lightshow When finished the modem restarts and you can use it again 1 6 5 1 New SCSupdate 2 0 By offering the free update tool SC...

Page 23: ...al information about PACTOR and the PTC automatically by email 2 1 Repairs If a problem occurs and it s necessary to send your SCS product to maintenance please take care of the following Always contact SCS by email before sending a modem You will be supplied with return instructions which are important for receiving modems from outside the EU Package the device with care Use suitable and enough p...

Page 24: ...unit The inputs are also protected by a self resetting fuse 3 2 USB The PTC IIIusb is a USB 1 1 device and can be operated in an USB 2 0 environment as well The connection to the computer is done with the attached USB cable For USB operation an appropriate driver needs to be installed on your computer This driver is on the SCS CD that comes with the modem Below you find a short description on how ...

Page 25: ... between the modem and the PC can be eliminated Advantage The data stream signal of a USB interface is located in the middle of the shortwave bands Therefore the USB data signal cannot be separated from the shortwave signal being transmitted or received by simply filtering Mutual interference is possible especially where the antenna is located close to the modem PC setup ship borne installations M...

Page 26: ...and displayed as a symbol in the manager Now you need to pair the PTC IIIusb with the PC so that both will recognize each other next time Usually the manager offers you the pairing option when you double click on the symbol or when you select it and press the right mouse button After you have started the pairing you will be prompted to enter a key or password The last 8 characters of the PTC IIIus...

Page 27: ...e radio connected to it mostly ICOM radios and it is desirable that the modem immediately starts when the radio is powered on To archive this the rear dip switch 1 labeled with ON must be set In this condition the PTC IIIusb is always on when it has supply power It cannot be switched off any more with the sensor The modem can only be switched off by cutting the external power supply 3 4 2 BIOS Thi...

Page 28: ... optimized it is desirable to prevent noise from the input of the PTC IIIusb as far as possible Under no circumstances use audio processors The speech compressor of the transceiver will damage the PACTOR 2 signal in the same way as external DSP audio filters being so popular at the moment These external DSP audio filters create unpredictable signal propagation delays which are absolutely undesirab...

Page 29: ...rs 8 pole DIN cable The socket is wired as follows Viewed from the rear of the PTC IIIusb 8 7 2 6 5 4 3 1 Pin 1 Audio output from the PTC to the transmitter Pin 2 Ground Pin 3 PTT output to transmitter PTT line Pin 4 Audio input from the receiver to the PTC Pin 5 Optional power supply input Pin 6 Not used Pin 7 Not used Pin 8 Not used Figure 3 2 Connection to the transceiver NOTE Unfortunately the...

Page 30: ... cable is available completely assembled Refer to chapter 16 on page 193 Table 3 2 ICOM 8 pin connection The smaller ICOM transceivers e g IC 706 often use a 13 pin DIN plug for ACC Signal PTC Color ICOM 13 pin GND PIN 2 white PIN 2 PTT PIN 3 yellow PIN 3 AF OUT PIN 1 violet PIN 11 AF IN PIN 4 green PIN 12 POWER PIN 5 blue PIN 8 This cable is available completely assembled Refer to chapter 16 on p...

Page 31: ...1 AF IN PIN 4 green PIN 6 Table 3 6 Kenwood TS 50 connection The TS 480 has a 6 pin Mini DIN connector Signal PTC Color YAESU GND PIN 2 white PIN 2 PTT PIN 3 yellow PIN 3 AF OUT PIN 1 violet PIN 1 AF IN PIN 4 green PIN 5 This cable is available completely assembled Refer to chapter 16 on page 193 Table 3 7 KENWOOD 6 pin Mini DIN 3 5 3 Connection to Yaesu transceivers Some YAESU transceivers use a ...

Page 32: ...practice not the best way The audio input sensitivity of most transceivers is adapted to the output voltage of a common dynamic microphone 100 modulation is reached at low MIC Gain settings with 200 mV Peak to peak input voltage It is not recommended to use very high PSKAmpl values and compensate this by lowering the MIC Gain setting because this may already overdrive the first amplifier stages wh...

Page 33: ...C limit To prevent damage from the transceiver at continuous operation we recommend to limit the FSK output level to half of the maximum possible that means 50 W if the transceiver is made for 100 W at max 3 5 4 1 PACTOR 3 For optimum PACTOR 3 data throughput the transmit signal must be clean and undistorted Make sure that ground loops and RF feedback effects are avoided in your installation A 1 4...

Page 34: ...ontrol TxD TTL Transmit data from the PTC to the transceiver TTL level RxD TTL Receive data from the transceiver to the PTC TTL level CTS TTL Handshake signal from the transceiver to the PTC TTL level RTS TTL Handshake signal from the PTC to the transceiver TTL level TxD V24 Transmit data from the PTC to the transceiver V24 level RxD V24 Receive data from the transceiver to the PTC V24 level CTS V...

Page 35: ...controlled by the PTC IIIusb Just solder a 9 pole connector to the attached cable as shown in the following table below Signal PTC Color KENWOOD TxD PIN 3 yellow PIN 3 RxD PIN 8 red PIN 2 CTS PIN 4 green PIN 8 RTS PIN 2 white PIN 7 GND PIN 13 orange PIN 5 This cable is available completely assembled Refer to chapter 16 on page 193 Table 3 13 KENWOOD V24 3 6 2 Connection to ICOM transceivers Nearly...

Page 36: ...PTC IIIusb adjusts the frequency but could not read out it Signal PTC Color YAESU TxD PIN 9 pink PIN 3 GND PIN 13 orange PIN 1 Table 3 16 YAESU FT 757 Some Yaesu transceivers FT 920 FT 847 FT 1000MP have a 9 pole sub D connector and operate with V24 levels for transceiver control It s intended for direct connection to a COM port of a PC Also these transceivers can easily be controlled by the PTC I...

Page 37: ...apter 13 20 on page 175 3 7 GPS The PTC IIIusb uses a 3 pole screw terminator to connect to a GPS reciever This input is compatible with 5V TTL and RS232 V24 signal levels This pins are assignes as follows Figure 3 6 GPS connector The PTC IIIusb expects GPS data with 4800 baud and in NMEA format 24 ...

Page 38: ...tains IDLEs which means that the data package is not completely filled with user data In PACTOR STBY condition but not in Listen mode it serves as channel busy indicator and is lit when the PTC IIIusb detects the channel as being occupied In Packet Radio it serves as Carrier Detect CD indication When it is lit red or orange Error or Request condition a data or control packet contains corrupted or ...

Page 39: ...he frequency deviation is compensated and the phase is stable CON ISS CONnected is lit green permanently in AMTOR PACTOR Packet Radio connected condition In STBY condition it blinks in 1 second tick when an unread mail for the own address MYcall is contained in the PTC mailbox It flashes fast if the modem waits for a Bluetooth connection when the USB cable is not connected and Bluetooth option is ...

Page 40: ...e is displayed with the system prompt cmd or pac During link set up and while connected the PTC is in the converse mode Switching to RTTY or turning on the CW terminal also activates the converse mode Whereas in the so called converse mode characters from the USB interface are placed in the transmit buffer and are sent over the HF channel at the next opportunity In Converse mode commands to the PT...

Page 41: ... short form of the SERBaud command is SERB 5 3 Menus The PTC IIIusb commands are combined into different function groups so called menus The different menus are the following Packet Radio Audio functions FAX STTV Transceiver controlling System test Last not least the main menu with the PACTOR AMTOR RTTY CW PSK31 commands The command prompt indicates the menu you have already selected The following...

Page 42: ...peration or the HF modes especially that simultaneous operation of Packet and the HF modes in not possible In terminal mode the command prompt cmd pac aud indicates if the PTC IIIusb is available for the HF modes or if the DSP is actually programmed for Packet Radio operation there is only one exception described below If the pac menu is chosen out of the STBY condition cmd then the DSP is always ...

Page 43: ...ne for de initialization at program shutdown The PR command will be ignored with an existing PACTOR connect The PT command is ignored with an existing Packet Radio connect 5 6 Remote commands Some PTC commands are also available for the distant station via the HF link There are two control possibilities First Setting REMOTE 1 and BOX 0 With this setting all remote control commands via the radio li...

Page 44: ...f the PTC IIIusb The maximum allowable file length and the number of files in the mailbox is only limited by the amount of free memory The memory can be expanded up to 2 MByte Filenames may be a maximum of 10 characters long and should contain no special characters The PTC truncates all over long filenames after 10 characters no difference being made between upper and lower case letters Entering t...

Page 45: ... position Chapter 6 71 TRX Transceiver control Chapter 6 97 Table 5 3 PACTOR mailbox commands Of course it is possible to enter mailbox commands on the console With the DIR and LIst command you can check the mailbox contents Write saves the mail with Read you can read the mail and with DELete you can delete the mail 5 7 1 Multiple file operations All commands that contain a file number in the argu...

Page 46: ... in the PTC IIIusb by connecting to the BBS MYCALL of the PTC IIIusb The BBS callsign is set automatically to MYCALL 8 either at the first start when the Flash Call in the BIOS has been defined or when one s own PACTOR MYCALL has been set If for example DL1ZAM is given as the first PACTOR MYCALL then the PR mailbox can be connected to under the callsign DL1ZAM 8 The BBS MYCALL callsign of the PTC ...

Page 47: ...sting BBS connection by giving a disconnect command via the local terminal Received text is displayed in hostmode terminal programs e g GP exactly as usual and can be followed by the Sysop The Sysop can hereby notice which commands are given by the users In terminal mode the text output from the BBS channels are completely suppressed to prevent that the PTC IIIusb receives buffer filling and maybe...

Page 48: ...nology In fact underneath the impressive sounding name is nothing other than a network of marine coast stations that broadcast plain language messages using the SITOR B system at specific times This system is known to amateurs as AMTOR mode B or FEC It uses the usual 170 Hz FSK modulation system which is also an old and wide spread system in HF digital radio For NAVTEX only one MF channel on the f...

Page 49: ...ten into the mailbox by the NAVTEX processor can be accessed via PACTOR or Packet Radio 5 8 2 The NAVTEX System in Detail As mentioned above NAVTEX messages are sent in plain language using SITOR B coding To mark the beginning end and type of message NAVTEX uses a simple convention Every message begins with the characters ZCZC followed by a space Then follows the four figure message identifier plu...

Page 50: ...he PTC IIIusb mailbox and stores all incoming NAVTEX messages there The name of the message author is given as AUTO NAV The NAVTEX processor gives the complete four figure message header as well as the plain language name of the type of message E g CA03 Navigational Warning If the number of messages in the NAVTEX directory is exceeds the maximum allowed the NAVTEX processor deletes the oldest mess...

Page 51: ...s Bulletin S Space Bulletin X Special Bulletin Table 5 6 AMTEX message types Generally A is used as the area code Station ident Exceptionally S has been used 5 9 GPS The Global Positioning System GPS has very quickly become a standard for all areas that require exact positional information e g shipping in car navigation systems etc Today GPS receivers are cheaply available and widely used The PTC ...

Page 52: ...etup the APRS features the command APRS in the pac menu is available refer to chapter 9 8 1 on page 121 Also here the parts of the commands written in capital letters are necessary to enter to invoke the command The first argument following the APRS command usually acts as a sub command and selects a function The final parameters are defined with the arguments following this sub command If there i...

Page 53: ...nd compensated without any loss of sensitivity and this also with signals that are buried deep in the noise Because of this it is possible to remove a tuning display One can say with good conscience this is Plug and Play for shortwave The 3 6 firmware makes available a small band 500 Hz version of the Robust PR A wide band variant 2 kHz with similar characteristics and 4 times the speed is in gene...

Page 54: ...and will not be confused by the change overs of the PACTOR Duplex PTC appearing accidentally The following distinctiveness exists for the PTC IIIusb itself when switched to PACTOR Duplex 1 The CHANGEOVER bell is generally deactivated 2 Open files for the PTC internal mailbox will not be closed by a CHANGEOVER any more 3 Mailbox access of users with PACTOR Duplex are executed correctly the command ...

Page 55: ...GEOVER is executed while entering commands e g when the user operates PACTOR Duplex but enters the command very slowly It would be desirable if all of the mailbox programs for PACTOR could be modified in the way that they could also operate with PACTOR Duplex users without problems 5 12 3 PACTOR data transparency The PACTOR Duplex mechanism and the data transparency structure of the WA8DED hostmod...

Page 56: ...on Audio refer to chapter 7 page 97 5 14 The Hostmode The PTC IIIusb supports the WA8DED hostmode and an SCS specific extension the CRC hostmode For detailed information about the hostmode and the hostmode commands refer to chapter 5 14 page 43 Pay attention to the explanations concerning the TNC command refer to chapter 6 94 page 87 Here you find some important details for the hostmode and PACTOR...

Page 57: ...refer to chapter 6 43 page 63 If HCr is 1 the PTC IIIusb executes a CHANGEOVER for each line feed at a blank line That s convenient for direct QSOs The PACTOR listen mode can be switched on and off with the hostmode command L The JHOST command is not allowed in the initialization file of the hostmode program Only the commands mentioned for hostmode refer to chapter 10 should be used in the initial...

Page 58: ...h however markedly reduced printing errors Higher values 40 60 are recommended for APLINK where data is sent over multiple AMTOR links until the target box is reached and thus a minimum error rate is to be aimed at Higher values can however cause a problem when the resync rate climbs considerably This leads to higher values of transmitted errors as every AMTOR resync also contains a built in rando...

Page 59: ...unreadable text In an AMTOR QSO instead of using the usual change over sequence it is possible to use the normal PACTOR CHANGEOVER character The PTC changes the PACTOR CHANGEOVER character automatically into the sequence A break in is made using the normal BREAK IN character Bkchr 6 4 APower Default setting 0 Parameter X 0 200 minimal PSK amplitude This command allows the automatic transmitter pow...

Page 60: ...eration The phase error on receive caused by frequency offset is always relatively quickly compensated switching off this function which is essential for PSK operation is not possible AQrg 1 activates the second additional compensation method The PTC IIIusb pulls the two carrier frequencies of the modems DSP slowly towards the set value This in contrast to the pure error phase compensation also in...

Page 61: ...re no longer available for use You can leave the aud menu with the Quit or DD command For a detailed description of the audio commands refer to chapter 7 page 97 6 8 BAKup This command is to be used to back up the entire PTC mailbox After entering the BAK command the PTC requests a disk file to be opened and waits for the input of a CR which starts the actual back up procedure After the back up is...

Page 62: ... The computer also automatically calculates the best low pass filter for the baseband filtering according to the baud rate This gives excellent receiving characteristics that hardly vary from the theoretical ideal value After BAU the PTC answers with BAUDOT RTTY RECEPTION ACTIVE SPEED 45 BD and is ready to receive RTTY transmissions Changing to transmit is done with the CHANGEOVER character set wi...

Page 63: ...OR and AMTOR The BREAKIN character is a special command for a forced direction change from RX to TX BREAKIN Because this command is used very often the PTC accepts the BREAKIN character only directly in the converse mode that means that the command cannot be used after the cmd prompt The BREAKIN character may be changed to any other convenient character with this command at any time Ctrl B as BREA...

Page 64: ...fication of stations This increases the Overhead of the box only very slightly as the callsigns are given in small letters and thus lend themselves to efficient Huffman coding If the remote user wants enter a command with using the the two slashes are ignored and the command will be executed Direct box access has priority compared with the REMote parameter of the PTC The direct access is always po...

Page 65: ...EL character to the terminal 6 19 CHOchr Default setting 25 Ctrl Y Parameter X 1 127 decimal ASCII code of a character Defines the CHANGEOVER character CHOchr defines the CHANGEOVER character which is a special command for the change from TX to RX Because this command is used very often the PTC accepts this character only in the converse mode and not after the cmd prompt The CHANGEOVER character i...

Page 66: ...cters Too short arguments are ignored If the callsign is too long it will be truncated at the end If no argument is given the old or the default callsign will be called Connect can be repeated with different call signs until a connection is established In the connected condition the Connect command can be used to display the callsign of the distant station If no response is received after the numb...

Page 67: ...ted 6 22 4 Direct frequency entry With starting a PACTOR connect optional a frequency value separated by a comma can be entered after the target callsign This is valid for the connect command in the terminal mode e g PlusTerm as well as in the host mode cmd C dl1zam 3582 60 Return In this example first of all the PTC will send the frequency information to the TRX the TRX sets the VFO to 3582 600 k...

Page 68: ...lt setting PTC IIIusb DSP QUICC System Maildrop QRV Parameter String of 249 characters maximum There is only one connect text for PACTOR and AMTOR The Connect text is transmitted when CMsg is set to 1 and the PTC receives a connect In this case the PTC immediately switches into TX mode As the CTEXT input happens using the command interpreter one convention for the CR character has to be followed A...

Page 69: ...oximately 7 minutes and after QRT The CW identification is keyed with the PTT line The FSK output remains at the Mark frequency during the CW Transmission The AFSK signal amplitude is also keyed The frequency for AFSK is defined by the Center command in the Audio menu refer to chapter 7 page 97 The speed is set with the CWSpeed command With CWid 1 3 the CW identification is only given at QRT if it...

Page 70: ...ing the CW terminal characters from the keyboard that can be translated into Morse are transmitted as Morse code by the PTC If an argument is entered the decoder starts in the fix speed mode that means that automatic speed adaption is disabled This is recommended for recording commercial CW transmissions weather report etc whose speeds are known When nothing is input at the keyboard and the transm...

Page 71: ...hing to the CW Terminal one is always in the direct transmission mode Ctrl U and Ctrl D Increases Up or decreases Down the decoder speed by 1 16 the actual value This is mainly for use when the automatic RX speed adjustment is turned off Ctrl F Switches between automatic and manual RX speed adjustment fixed speed mode On switching between the two possibilities the present speed is taken without ch...

Page 72: ...acter length is not influenced by CWWeight The value of CWWeight influences the CW identification as well as the CW terminal 6 32 CYcle Default setting 2 Parameter 0 Always switching to short cycles 1 Always switching to long cycles 2 Adapt cycle length adaptive CYcle defines the cycle length used for a PACTOR 2 connect Usually it is just used for test purposes speed comparison etc and is describe...

Page 73: ...ilbox entries divided into two groups private callsign as subdirectory and public bulletin mail and the free memory available in the mailbox If DIR contains as a parameter the name of a subdirectory then the contents of this subdirectory will be listed e g DIR test shows all files in the subdirectory test refer also to LIst in chapter 6 48 page 64 DIR without parameter appears similar to below Mai...

Page 74: ...ght to moderate adjustment of the frequency response of the PACTOR 3 transmit signal Some IF filters used in standard SSB transceivers already attenuate the edges of only 2 kHz wide signals due to a poor frequency response As a countermeasure EQ allows to compensate for this effect Please do only use the EQ command if you really know the actual transmit frequency response of your transceiver 6 39 ...

Page 75: ...detailed description of the FAX and SSTV commands refer to chapter 10 6 41 FEc This command starts an AMTOR FEC transmission Mode B When the AMTOR prompt is active then this command has the same effect as the CHANGEOVER character After approx 4 minutes of pure idle transmissions an automatic QRT is carried out 6 42 FSKAmpl Default setting 60 Parameter X 30 3000 AF output voltage peak to peak in mV...

Page 76: ...st of all commands The PTC contains a short description of every command so that the manual does not need to be continually consulted These descriptive messages can be obtained by using Help followed by the required command Help bau or in shortened form h bau From remote Help results in only those commands that can be remote controlled being listed A thorough description of each command can also b...

Page 77: ...ng 128 Parameter X 20 128 Number of characters before an auto linefeed Auto linefeed after X transmitted characters word wrap The auto linefeed is turned off with the value 128 6 48 LIst Remote Lists the contents of a directory in the PTC mailbox The short form L for the LIst command is also accepted by the remote station as in this case no possible confusion with Listen can occur The output forma...

Page 78: ...tatus is given in Listen mode 6 49 1 PACTOR 3 For achieving good monitoring results on PACTOR 3 the frequency offset should kept lower than 20 Hz Of course an SNR appropriate for the actual speed level is necessary for error free reception Nevertheless monitoring results are naturally inferior to ARQ connections under same conditions because no retries can be requested Opposed to PACTOR 2 monitori...

Page 79: ...by multiple simultaneous logged in users the logbook entries might not appear in strictly chronological order 6 52 LOGIn Remote In order to allow access to the PTC mailbox in AMTOR a user station must first Login using the LOGIn command e g LOGI DL1ZAM The user s callsign is thus made available to the PTC mailbox Only after a correct LOGIn can the AMTOR user station send read or delete files from ...

Page 80: ...55 MAXDown Default setting 6 Parameter X 2 30 number of error packets before down speed Selects the down speed parameter for automatic speed adaption MAXDown determines how soon the system steps down to a lower speed but more robust mode during poor channel conditions 2 fast 30 slow Example MAXDown 7 i e the PTC switches down after receiving 7 error packets in a row 6 56 MAXError Default setting 7...

Page 81: ...mum value of MAXSum depends on the condition on the HF channel The worse the condition the higher should MAXSum be set in order to be able to pass any information at all 6 58 MAXTry Default setting 2 Parameter X 1 9 maximum number of speed up attempts MAXTry determines how often the PTC repeats a packet with the next speed level during an attempt to speed up the transfer rate 6 59 MAXUp Default se...

Page 82: ...II mode MOde 0 makes the controller transmit ASCII anyway Doing this should only be necessary in very special cases Automatic mode also works on characters exceeding 127 decimal Therefore 7PLUS files may be transferred without any user intervention The parameter 2 is effective only with a PACTOR Level II link With Level I contacts the system behaves as if the parameter 1 had been chosen The automa...

Page 83: ...ing is different to SCSPTC it copies the PACTOR MYCALL into all PACKET channels which still contain SCSPTC and replaces it by the valid MYCALL The same procedure is performed if the MYcall command is executed with a valid call as argument in the cmd menu This ensures that after a RESTart or after the first power on all calls are set to a valid value 6 63 MYLevel Default setting 3 Parameter 1 The P...

Page 84: ...s allowed in the NAVTEX directory If this number is greater than 0 then the NAVTEX processor is activated The type of messages A to L see above that the NAVTEX processor should store The following default values are preset for instance after a RESTART of the PTC Number of AUTO NAVTEX directory entries 0 AUTO NAVTEX is DISABLED Selected NAVTEX area s ALL Selected MESSAGE TYPES A Navigational Warnin...

Page 85: ...es to receive messages from a few special coast stations these can be set by using the command NAV AREA This can often be a useful choice as a skipper in the Mediteranean Sea will have presumably no interest in navigational messages concerning the North Sea or Baltic The area codes allocated to the individual coast stations can be easily found out by inspecting the message contents If one wishes t...

Page 86: ... can switch between normal NAVTEX operation AMTEx 0 and AMTEX configuration AMTEx 1 The default AMTEx parameter is 0 The PTC IIIusb is thus preconfigured for normal NAVTEX operation One switches to the AMTEX configuration with the command cmd NAVtex AMTEx 0 Return As usual it is only necessary to type the letters given in capitals as well as the argument When the AMTEX configuration is switched on...

Page 87: ...t slow transmission speed Switching is disabled with the command NUL 0 6 67 PACket The PACket command or PAC for short switches on PTC IIIusb Packet radio commands the input command prompt having the form pac and the Packet radio commands are then valid refer to chapter 9 page 117 The PACket command can also have a single command from the pac menu as argument As with the other sub menus of the PTC...

Page 88: ...ter start of the contact provided the initial clock difference did not exceed 30 ppm When called without an argument the actual total phase correction manually and system generated initial values are displayed This is a powerful feature that you can use for aligning your PTC crystal oscillator without any measuring instruments following these steps Perform a master call to a station with a known h...

Page 89: ...n order that both forms of modulation should have the correct average power level A simple automatic adjustment of the PSK amplitude by a factor 1 45 does not give a satisfactory result as the ALC control characteristics are different from transmitter to transmitter The input sensitivity of most transceivers is adjusted for the output level of an average dynamic microphone With 200 mV peak to peak...

Page 90: ...SK amplitude must be adjusted with the PSKAmpl command alone The internal resistance of the AF output level of the PTC IIIusb is 330 ohm and real 6 73 PSKTerm Starts the PSK31 operation of the PTC IIIusb For further information refer to chapter 11 page 157 6 74 PT Returns to PACTOR from the AMTOR RTTY PSK31 or CW modes Activates the PACTOR input prompt cmd 6 75 PTChn Default setting 4 Parameter X ...

Page 91: ...o 6 in the current directory R TEST 3 Reads message number 3 in the TEST directory R DL2FAK Reads message no 1 for DL2FAK if only one message exists Outputs the contents of the DL2FAK directory if more than one message exists R DL2FAK 1 3 Reads messages numbers 1 to 3 for DL2FAK R PTCPLUS 4 Reads from message number 4 onwards in the PTCPLUS directory 6 79 RELOad RELOad overwrites the present BBS c...

Page 92: ...a CR A single command does not need the CR to end it if a CHO character immediately follows the command System messages of the remote controlled PTC are transmitted in lower case as this gives better Huffman compression and a clearer display REMote 2 additionally enables the full transceiver control command set All TRX commands as TRX TRX command at BOX 1 or TRX TRX command at BOX 0 is available T...

Page 93: ...ts may be received as per the original on the screen of the other station Send in the disconnected condition is identical to the Read command Again here all extra information file header EOF text path text is suppressed 6 85 SERBaud Default setting auto Parameter baudrate auto The USB driver of the PTC IIIusb is pre set to the given baud rate of 115200 baud Baud rate settings in PC programs do not...

Page 94: ...O SHow C shows information on all the control character settings of the PTC It is thus quick and easy to see if essential characters have been changed QRT CHARACTER ASCII 4 ESCAPE CHARACTER ASCII 27 CONTROL CHARACTER ASCII 22 CHANGE OVER CHARACTER ASCII 25 BREAK IN CHARACTER ASCII 25 SHow P displays the essential system parameters The timing for the transceiver control and the parameters that infl...

Page 95: ...l digital squelch can reduce the accidental received QRM drastically The ZCZC NNNN autostart can be activated setting the squelch parameter to a value between 100 and 200 If the squelch value is set to 140 the PTC IIIusb operates with the ZCZC NNNN autostart and additionally with the normal analog squelch of 40 value minus 100 This means that also during open autostart squelch the reception is int...

Page 96: ...instance directly after the start of the terminal program Hints for programmers Through the PACTOR software the status reply may be delayed by 150 ms After a system boot power on RESTart or RESEt the status polling is ready after the first cmd prompt Construction of the status byte status level 1 Bit 7 6 5 4 3 2 1 0 Meaning 1 MODE D STATUS Bit 7 always 1 to avoid control codes XON XOFF etc Bit 3 D...

Page 97: ...channel busy status has been activated it remains so for at least 3 5 seconds An optical output is also given with the TFC LED lighting up when the channel is busy The Channel busy status is only given in the STBY condition not in Listen mode L 1 6 91 SYStest The system test is not normally required by the PTC user but has been included here for the sake of completeness SYStest is purely a tool to...

Page 98: ...pendently Terminal mode 3 arranges the delayed echo to be signaled by a Ctrl C not a Ctrl B as it is in terminal mode 2 The normal RX text is still signaled by a Ctrl B This convention makes it possible to divide the screen into three parts The first window Ctrl A for system information and TX text the second window Ctrl B for RX text and the third window Ctrl C for delayed echo text Terminal mode...

Page 99: ...cription The terminal mode 5 also extends the command prompt Every command prompt as in terminal mode 4 is proceeded with a Ctrl D after every Ctrl D however follows a byte with prompt information Bits 5 7 contain coded information about the prompt sort Bit 7 Bit 6 Bit 5 Prompt Bits 0 4 0 0 0 Not allowed 0 0 1 cmd 0 cmd 1 AMTOR 2 MONITOR 3 RTTY 4 CW 5 PSK31 0 1 0 trx always 0 0 1 1 sys always 0 1 ...

Page 100: ...sb displays in the main menu cmd Switching to a submenu the prompt changes so that the user has the advantage to know directly which menu is selected Some hostmode programs test exactly if a controller with TF is connected most of all to determine if the used controller is already in the hostmode or still in the terminal mode For this purpose as response to the ESC character the asterisk prompt is...

Page 101: ...command TNC 0 within the PTC initialization file of non hostmode programs Using this option the PTC will work as a normal PTC independent from how it was used before and will provide the prompt that the non hostmode terminal programs expect Similar to what is described above one can add the command TNC 2 into the de initialization file of the non hostmode program so every hostmode program can be s...

Page 102: ... default in RTTY and AMTOR the TRX must be set to USB operation 1 High tones 2100 Hz Mark frequency 2300 Hz Space frequency If TR 0 default in RTTY and AMTOR the TRX must be set to LSB or FSK 2 The freely definable MArk and SPAce tones are used We recommend TR to be set to 0 and to operate using USB whereby the Mark frequency should always be higher than the Space frequency Using this convention a...

Page 103: ...d may be said to be fed through This command for example would change the frequency of a connected transceiver directly to 14079 0 kHz without having to divert to the trx menu cmd TRX Frequency 14079 0 Return For a detailed description of the TRX commands refer to chapter 13 page 165 6 98 TXDelay Default setting 4 Parameter X 1 31 PTT delay in X 5 msec Sets the TX keying delay x times 5 ms The TX ...

Page 104: ...rding to prevailing conditions Set the number of packet repetitions to 3 cmd U 3 Return Now with the following command a 200 baud transmission can be started cmd U 2 Return Unproto possibilities for PACTOR I Parameter Speedlevel Packet definition 1 100 Bd FSK standard method for Level I CQ calls 2 200 Bd FSK Unproto possibilities for PACTOR II Parameter Speedlevel Packet definition 3 100 Bd DPSK s...

Page 105: ...imately 4 minutes of idle transmissions an automatic QRT is carried out 6 101 UPDATE The UPDATE command renews the PACTOR firmware in the Flash ROM of the PTC IIIusb It should only be used together with the corresponding program on the PC which automaticly performs the update procedure with all necessary handshake and control mechanisms 6 102 USer Remote The User command enables an overview of all...

Page 106: ...eed Data Transfer Protocol Professional Marine Firmware V 4 1 C 1994 2012 SCS GmbH Co KG Germany BIOS Version 2 12 detected Packet Radio Port SCS DSP MULTI MODEM detected Parameter with the version command terminal mode displays the most important modem properties in a special format This eases the automatic configuration of terminal programs and therefore is mainly important just for software dev...

Page 107: ...lso with single port devices all 4 digits are always displayed 5 PACTOR 3 License N no permanent license installed V permanent license installed default for the PTC IIIusb 6 106 Write Remote Default setting none Parameter Filename File or directory name Title Optional title of the message From remote the same function is also available as Send command Enables files to be sent to the PTC mailbox Th...

Page 108: ...etc are not allowed and an error message will occure in this case 6 107 XUser The XUser command is used to manage the user list The PTC IIIusb firmware allows to define user specific access priorities i e that it is possible to define in a user list if for example the user DK9FAT is permitted to use the PR PACTOR gateway or if he is allowed to read private messages for other callsigns from the Pac...

Page 109: ...ould not be longer than 6 because in PR the length is limited to 6 characters by the protocol Callsigns extensions e g F DL6MAA M are inadmissible and not useful because of incompatibility with the PR protocol The PTC IIIusb cuts all characters appearing after a special character in the callsign automatically From the entry DL6MAA 10 is automatically DL6MAA generated The entry of a SSID in the cal...

Page 110: ...e CW filter Sets the center frequency of the CW filter continuously between 300 and 2700 Hz Refer also to command CWfilter chapter 7 3 and the command CWTerm chapter 6 30 The Center command also adjusts the audio frequency of the CW Terminal chapter 6 30 of the PTC IIIusb send and receive sides In firmware releases prior to version 1 12 the CW Terminal used the current Mark frequency which sometim...

Page 111: ...inverter with an inversion frequency of 3600 Hz aud Invert 3600 Return 7 8 Notch Activates the automatic N times notch filter All systematic signals are heavily attenuated The algorithm used leads to considerably less signal distortion of speech signals compared to simpler DSP notch filters 7 9 Peak Activates the automatic N times peak filter This may be considered as a phase linear Auto Correctio...

Page 112: ...ution of 1 Hz The command without an argument delivers a tone of 1000 Hz The command can also be used to setup a dual tone generator For this the second frequency is entered after the first one separated by a space Both tones are generated simultaneously which is well suited for measurements of intermodulation distances of transmitters and power amplifiers Example aud TO 1000 2000 Return generates...

Page 113: ...al 8 bit serial transfer This allows full compatibility with the widely used radio teleprinter programs such as Zorns Lemma The PTC IIIusb operates in all special MODEM functions as a FULL DUPLEX modem This means the appropriate demodulator generates the correct data even during the transmit phase This is in most cases however only of interest for testing purposes 8 2 Basic info concerning FAX and...

Page 114: ...z i e 2300 Hz and black is represented by 1900 400 Hz or 1500 Hz A gray scale is given by the appropriate frequencies between the limits represented by 1500 and 2300 Hz The Nyquist bandwidth associated with FM FAX is approximated by the formula pixel rate 2 shift With a pixel rate of 1600 sec one calculates a Nyquist bandwidth of 800 400 400 800 2400 Hz The PTC IIIusb allows a resolution of up to ...

Page 115: ...tely this freedom in transmission times has led to an unnecessary number of different SSTV sub standards some of which are poorly documented A real technical requirement for these multiplicity of standards is not to be found By limiting the SSTV practice to a few modes it is possible to keep a reasonable overview of the entire SSTV scene Like in the early steam SSTV period the modern systems still...

Page 116: ...sary Both problems are solved with the new modem command JVComm within the fax menu activating a new transmission routine On the receiving side the JVComm modem of the PTC IIIusb has the same behavior as the previous FMfax modem also activated within the fax menu The only difference is that the PTC provides no receiving data while the JVComm modem of the PTC IIIusb is in transmission state That me...

Page 117: ...ular end of a picture It must be added to each picture to deactivate the transceiver directly after picture end 255 Ends the JVComm modem Jump to the STBY mode of the PTC Direct analysis not via data buffer 8 4 Fax menu commands When in the main menu cmd prompt the FAX command leads to the fax menu The menu announces itself only with the prompt fax the description fax is misleading because within ...

Page 118: ...command Note concerning the data rate during MODEM operation The received data is sent with the maximum possible speed to the serial interface in all MODEM operating modes There are no pauses between the individual characters not even through excessive use of the Packet Radio function of the PTC IIIusb multi tasking With an MBaud rate for example of 57600 bits sec there is a new value available fo...

Page 119: ...h may be pre set using the FResolut parameter The steepness of the FM detector may be pre set using the Deviation parameter The output values reach from 0 to 255 Measured values smaller than 0 are output as 0 Values greater than 255 are limited to 255 by the PTC IIIusb The center frequency is exactly 1900 Hz With a frequency of 1900 Hz as AF input the PTC IIIusb always gives out the appropriate va...

Page 120: ... bits of every byte to indicate the synch pulse Bits 0 and 1 are set to 1 in the resting state As soon as the PTC IIIusb recognizes a correct synch pulse on the 1200 Hz frequency it sets the bits 0 and 1 to 0 for the time the synch pulse occurs Note the VIS code is at present not processed by the PTC IIIusb and therefore bit 2 is actually redundant for the signaling condition The small decrease in...

Page 121: ...he demodulator may be changed to 200 300 or 400 baud signal rate by using the FSKBaud Parameters command The PTC IIIusb is therefore highly suitable when used in the MODEM operational mode FSK as a demodulator for widely differing transmission methods Packet Radio with 300 Baud and multi FSK systems such as PICCOLO etc may be received when the appropriate PC program is available The NFSK demodulat...

Page 122: ...usb and TFX emulates a real hostmode TNC for 300 baud Packet that can be operated with a hostmode terminal program such as GP The command PR300 starts the TFX compatible 300 baud PR modem TFX should be used with hardware DCD turned on The MARK tone is the one also valid for PACTOR and the SPACE tone is always located exactly 200 Hz below the MARK tone The TFX program is available at nearly every P...

Page 123: ...e frequency modulator in the DSP operates phase continuous and therefore produces a very clean and spectrally narrow signal An output bandpass filter has thus been omitted The steepness of the frequency modulator is independent of the Deviation parameter or other settings The maximum possible shift of the transmitted FSK signal however is thus limited to 800 Hz In order to generate the synchroniza...

Page 124: ...Pixel sec Gives the maximum possible time resolution of the received signal in AM FAX Also the AResolut parameter adjusts the bandwidth of the input bandpass filter appropriately With noisy signals it is recommended that the AResolut parameter is set to 0 as the effective signal to noise ratio is thereby increased The maximum resolution is as follows 0 1680 pixels sec 1 2500 pixels sec 2 3400 pixe...

Page 125: ...provided the received signal has a baud rate of 200 or less as the effective signal to noise ratio is thereby increased Baud rate settings 2 200 Bd 3 300 Bd 4 400 Bd 8 8 6 Deviation Default setting 400 Parameter X 100 1000 shift of the FM FAX demodulator in Hz Sets the steepness shift of the FM FAX demodulator NOTE in JVFAX mode the shift can be changed using special control bytes independently of...

Page 126: ...on the serial interface If there is no synch pulse present then the two lowest bits 0 and 1 are set to 1 The PTC IIIusb erases the two lower bits for the period of a synch pulse 8 8 10 SMode Default setting 1 Parameter X 0 15 SSTV sub mode Sets the SSTV sub mode required The SMode parameter is only used for the SSTV line synch processing as it is only here that specific information about the vario...

Page 127: ...g on the CTS line of the serial interface When CTS is active the PTT line for the shortwave port is activated The PTT line is de activated turned off with inactive CTS When in the send condition the PTC IIIusb measures the incoming data as square wave modulation data on the RxD PIN The zero crossing point is measured very exactly and then modulates the VCO in the DSP The PTC IIIusb has a very good...

Page 128: ...a bandwidth of approximately 2 5 kHz The audio limit frequencies that should be transmitted are 1900 1250 Hz and 1900 1250 Hz or 750 Hz and 3150 Hz The frequency band for FAX SSTV appears to be shifted about 400 to 500 Hz higher in frequency With normal SSB reception the higher FAX SSTV tones suffer great attenuation and thereby cause asymmetrical reception In order to help this situation it is re...

Page 129: ... The expression DAMA is added to the header of the monitored packets if the packet is received by a DAMA Digi The DAMA mode needs not be activated by the user The PTC IIIusb automatically notices if you are working with a DAMA Digi or not and behaves respectively 9 2 Modern Times We hope you have already recognized the following warning The PTC IIIusb expects all time parameters in milliseconds Th...

Page 130: ... center frequency of the audio signal is fixed to 1500 Hz On the receive side the same side band as the transmit side must be used We generally recommend USB With Robust PR modulation selected the PTC assumes that a connection will be via a HF Channel and adjusts a few parameters automatically MAXFrame is automatically administrated the value given by the user does not matter RETries is automatica...

Page 131: ...ding conditions on the channel The audio output level for transmission is the FSKA value refer to section 6 42 on page 62 from the cmd menu as usually the HF transceiver is used for 300 baud HF Packet purposes and the settings from PACTOR AMTOR are proper The 300 baud modem generally operates with 200 Hz frequency shift The center frequency is calculated automaticly from the tone pair set with the...

Page 132: ...correctly in the setup of the program 9 6 SMACK SMACK4 means Stuttgart s Modified amateur radio CRC KISS It represents a KISS mode with added checksum for data protection SMACK is supported by many KISS capable systems To switch into the SMACK mode first the normal KISS more needs to be entered KISS master and KISS modem then automatically negotiate if CRC protection SMACK can be enabled A complet...

Page 133: ...minates the transmission after 20 minutes The APRS beacon uses as sender call sign the MYcall of the virtual channel 0 As long as this call sign is not set the APRS beacon cannot be activated The MYcall of the virtual channel 0 is automatically set to the Pactor MYcall after a RESTart so that normally only a single MYcall entry is necessary to set all PACTOR as well as Packet Radio APRS MYcall to ...

Page 134: ... is recommended to select the first digitpeater RELAY 9 8 1 3 APRS POsition Default setting NONE Parameter XXXX XXS N YYYYY YYW E Allows the entry of the position for the FIX operation Aprs 2 see 9 8 1 The position must be entered exactly in the correct format for Latitude Longitude which means degrees including leading zeroes directly followed by minutes with 2 decimal places and including the di...

Page 135: ...e A SY command normal way displays the actual parameter settings however with a current symbol additionally with a short description in square brackets E g a13 Home HF Here is a selection of current symbols or their numbers 6 HF Gateway 7 Small Aircraft 13 House QTH VHF a13 House HF 15 Dot 27 Campground 28 Motorcycle 30 Car 47 Balloon 50 Recreational Vehicle 53 Bus 56 Helicopter 57 Yacht sail boat...

Page 136: ...er the Baud command shows the currently set baudrate If a valid baudrate is given as a parameter the DSP is programmed respectively Valid values are R300 R600 300 1200 9600 and 19200 baud For 9600 and 19200 baud operation a suitable transceiver is necessary With a value of 300 additionally the tuning display is activated refer to chapter 9 4 on page 119 9 8 3 CBell Default setting ON Parameter OFF...

Page 137: ...r OFF Time stamp off ON Time stamp on Activates the display of time stamps on connect and disconnect messages 9 8 8 CONVerse Manually activates the converse mode This function is seldom needed as the PTC IIIusb automatically switches to the converse mode after a successful link up Alternatively a K may be used as abbreviation for CONVerse The Converse mode can be terminated with the entry of ESC C...

Page 138: ...g disabled ON Digipeating enabled Enable or disable digipeating using the own station 9 8 12 Disconnect Ends an AX 25 link If there is still data to be sent to the partner station then this data is transmitted first before the disconnect is carried out If the Disconnect command is given twice one after the other then the link is broken immediately corresponding to DD in PACTOR 9 8 13 FRack Default...

Page 139: ...S capable controller e g TNC3 The KISS mode is terminated by a system reset power off on cycle but can also be terminated by software with sending the decimal byte sequence 192 255 192 The termination by sending the byte sequence is usually done automatically by the software as well and may just once be configured correctly in the setup of the program 9 8 17 MAXframe Default setting 7 Parameter X ...

Page 140: ...eed This has the effect that CR LF in PR Terminal mode no longer causes incompatibility with DieBox mailbox systems If the character is set to ASCII 128 then a special filter is activated which filters out all CONTROL characters range 0 31 except CR LF and TAB Set filter for LF and BELL pac MF 10 Return 9 8 20 Monitor Default setting 0 Parameter X 0 6 frame type Switch monitor on and off Values gr...

Page 141: ...ill give the following message Welcome to DL1ZAM s PTC IIIusb Mailbox Please type H for help The MText always follows the message from the automatic mail notifier i e NO new MSG for you or 2 new MSGs for you or similar The MText cannot be turned off 9 8 23 MYAlias Default setting SCSPTC Parameter CALL Alternative station callsign MYAlias is handled as MYcall for incoming connects and can also be u...

Page 142: ...sign of the PR mailbox Identical to the MYcall command in the pac menu however sets the Mycall of the PTC IIIusb PR mailbox BBS MYCALL The BBS call is set automatically to MYCALL 8 either at the first start when the Flash Call in the BIOS has been defined or when ones own PACTOR MYCALL has been set If for example DL1ZAM is given as the first PACTOR MYCALL then the PR mailbox can be connected with ...

Page 143: ...evel cmd prompt The Box command relates to PACTOR AMTOR only The PRBox command to Packet Radio only 9 8 29 Quit Exits the Packet mode Returns to the cmd input prompt 9 8 30 RESptime Default setting 500 Parameter X 1 30 000 response time delay Sets the value for the AX 25 timer 2 T2 in milliseconds After receiving a packet the PTC IIIusb waits the time T2 to check if another packets follow If so al...

Page 144: ...efines the period between these times 9 8 34 TRACE Default setting OFF Parameter OFF Trace mode switched off ON Trace mode switched on In the terminal mode the PTC IIIusb provides the so called Trace mode for Packet Radio The TRACE command activates or deactivates a special display mode for all frames shown in the monitor channel The PTC IIIusb sends the trace mode data as Hex dump as ASCII or as ...

Page 145: ... Default setting CQ Parameter Call Callsign for Unproto Unproto sets the target callsign for the Unproto operation To start an Unproto transmission just enter the Converse mode with K and everything that is then typed and ends with Return is transmitted by the PTC IIIusb Esc returns the pac prompt the entry of K then ending the Converse mode 9 8 38 USers Default setting 4 Parameter X 0 31 number o...

Page 146: ...al is off line and the configuration is correct USers 0 or Y0 then all calls irrespective of if they are the normal MYCALL the MYALIAS or the BBS MYCALL will be transferred to the PTC mailbox The USers command has no effect on self initiated connects the number of channels is not limited for the user It is thus possible with Users 0 to initiate up to 31 PR connects in parallel ...

Page 147: ...prove it Especially for new ideas like extended hostmode and AX 25 protocol expansions like as DAMA TheFirmware was and is the basis for development Because of these advantages the wide distribution of TF and the always more perfected hostmode programs the hostmode became the standard for TNC controlling But the disadvantages of the hostmode shall be mentioned too The hostmode progam has to poll t...

Page 148: ...reliability of a Packet Radio connection depends on the time parameters Because of this check the initialization files of programs you use in advance and very carefully Often the added examples are designed for a TNC 2 But the TNC 2 expects the time inputs in 10 ms steps e g for a TxDelay of 100 ms the value 10 has to be given for a TNC 2 But the PTC IIIusb needs the value in milliseconds that mea...

Page 149: ...tmode Terminal Mode Hostmode Terminal Mode Hostmode Baud B MCon M CHeck T3 Monitor M CMsg U MStamp K Connect C MYcall I CONStamp K PErsist P CText U RESptime T2 Disconnect D REtry N FRack F SLottime W KISS K TXdelay T MAXframe O Users Y Table 10 1 Commands Terminal mode hostmode 10 4 1 C Default setting none Parameter target call Digi1 Digi2 Connect establishes a AX 25 link to the target callsign ...

Page 150: ...e channels This command is only used by the hostmode program The user cannot enter this command 10 4 5 I Default setting SCSPTC Parameter CAll Station callsign Sets the station callsign which can be individually set for each channel the callsign from channel 0 being used after a disconnect 10 4 6 JHOST Default setting 0 Parameter 0 Exit hostmode 1 Start hostmode 4 Start CRC hostmode Switches to th...

Page 151: ...r 10 4 10 N Default setting 10 Parameter X 0 255 number of repeats Sets the maximum number of repeats and if this value is exceeded then the PTC IIIusb gives out the message LINK FAILURE with call 10 4 11 O Default setting 7 Parameter 1 1 7 Number of unacknowledged packets Maximum number of unacknowledged info packets I frames in a link Maxframe also sets how many packets the PTC IIIusb transmits ...

Page 152: ... 15 PT Switches the PTC IIIusb to PACTOR mode and loads the DSP respectively This command is necessary that the PTC IIex can accept PACTOR connects attempts from a distant station after e g having just finished a Packet Radio connect and the PTC IIex still is in Packet mode Also refer to chapter 5 5 on page 29 10 4 16 T Default setting 100 Parameter X 0 30 000 TxDelay in milliseconds Sets the time...

Page 153: ...ons and a further station attempts to connect this connect request will be refused The Y command allows any incoming PR connect to be transferred to the PTC IIIusb PR mailbox but only if Y has to be set to 0 This will allow for example that on exiting the terminal program e g automatic de initialization with Y0 in GP the PTC IIIusb can be brought to a condition where a connect using the normal MYC...

Page 154: ...el 252 is always 256 The sampling rate number of 8 bit samples i e pixels per second is calculated as baudrate on the serial user interface COM port divided by 32 or 16 The baudrate on the serial user interface of the modem should be chosen as high as possible higher than 57600 Bd to achieve a good FAX resolution For example 115200 Bd on the serial port yield a FAX sampling rate of 3600 or 7200 pi...

Page 155: ...e program 10 4 24 S If hostmode FAX reception refer to 10 4 22 Page 142 is activated the additional hostmode command S is available It allows access to the 16 bit wide audio samples from the A D converter on the HF port The S command does not require a parameter The audio sampling rate is 9600 samples per second and cannot be changed As soon as the modem recognizes a S command it starts acquiring ...

Page 156: ...0 baud operation a suitable transceiver is necessary 10 4 28 C This is identical to the CLR command in the main menu of the terminal mode It works only on the PACTOR channel 10 4 29 E Default setting 6 Parameter X 1 7 brightness value Identical to the BRightn command of the main menu in the terminal mode This serves to set the brightness of the LED display between 6 and 100 The parameter 1 is equi...

Page 157: ...ly be appropriately extended to contain this feature and choose the extension required automatically Manual switching of the hostmode expansion is not to be recommended due to possible incompatibilities 10 4 33 O Performs a CHANGEOVER This command can also be used in the receiving condition IRS In this case it leads to a BREAKIN During transmission ISS the O will be executed when all characters in...

Page 158: ...n the modem has already detected the beginning of a user access on the PACTOR HF port In principle this problem can already be solved by using the scan stop signal the PTC provides but only if the external scanner immediately recognizes the scan stop signal Unfortunately so called latency time Windows is introduced in practise Latency time delays the scan stop signal and thus can cause prohibited ...

Page 159: ...o called extended hostmode The extended WA8DED hostmode has established itself as a de facto standard for communication between TNC PTC and PC control programs The extended hostmode makes the polling of the channels much easier and thus reduces the polling overhead In the extended hostmode channel number 255 is dealed in a special way A G command to channel 255 leads to the output of 255 x y z 0 f...

Page 160: ... G1 The parmeter determines how many status bytes are sent back to the PTC as a response to the G poll The number of bytes calculates as paramater value plus 1 Thus the command G0 is compatible with the usual G poll without argument because it yields exactly ONE status byte the old normal status byte Therefore a maximum of 4 status bytes can be requested by the application software The contents of...

Page 161: ... receiver sends The PTC IIIusb buffers 32 sets of NMEA data internally This NMEA channel is also included in the extended hostmode channel 255 which means that the usual poll on channel 255 is sufficient to determine if there is new NMEA data available on channel 249 10 9 CRC hostmode The expanded WA8DED hostmode extended hostmode has established itself as a de facto standard for communication bet...

Page 162: ...e transferred with a lengh of max 1024 bytes on the FAX channel 252 in the direction PTC to PC The added 2 length bits are bit 4 and bit 5 of the code byte JHOST5 especially enhances weather FAX receiption with the use of the Bluetooth interface by compensating the probably occuring higher latency time Certainly also with the use of the USB or RS232 interface the FAX receiption timing becomes less...

Page 163: ...his removes the 0 bytes inserted by the packet transmitter The byte de stuffing begins directly after the first byte after the recognized 170 170 header After every byte with the value 170 one byte is erased providing it is a 0 byte If the following byte does not have a value of 0 then error handling is carried out refer to chapter 10 9 5 page 152 The MASTER uses a 1 bit packet counter using bit 7...

Page 164: ...uest condition If a packet is correctly received and the request flag is identical to the last correctly received packet Bit 6 of the CMD INF byte must be erased Refer to the text above Reaction of the SLAVE to various conditions Reaction of the SLAVE to the NACK condition Transmission of the special request packet 170 170 170 85 direct request for a repetition of the defective packet without wait...

Page 165: ... start of the CRC hostmode the internal REQUEST bit in the SLAVE PTC should be set to not defined so that either 1 or 0 are valid as REQUEST BIT in the first transmit packet from the MASTER Thus when the CRC is correct at the SLAVE an ACK condition follows Independent of the above it is recommended that the first transmit packet from the MASTER after a hostmode start or program start should have b...

Page 166: ... index FOR j 0 TO 7 DO BEGIN IF Odd Data XOR accu THEN accu accu shr 1 XOR 8408 ELSE accu accu shr 1 Data Data shr 1 END crc_table index accu END Build table END Begin InitCRC Expand CRC Table crc ffff Start value of the CRC Register Calculating the CRC follows for every input byte CALC_CRC_CCITT must be called once CALC_CRC_CCITT 04 Give input bytes in decimal here CALC_CRC_CCITT 01 CALC_CRC_CCIT...

Page 167: ... HIGHBYTE 153 When checking the CRC reception one also calculates both the transferred CRC bytes into the CRC value The new CRC value so obtained must equal F0B8 if the block has arrived correctly Alternatively one can calculate the CRC only using the data bytes without having to include the CRC bytes If one inverts the two bytes so calculated then the result must match up with the two received CR...

Page 168: ...en the back space character is included 11 2 Activation and use of the PSK31 terminal The command to activate the PSK31 mode is PSKTerm in the cmd menu Command parameters are not required and will be ignored if given After turning on the PSK31 terminal the PTC IIIusb is in the receive condition Various PSK31 relevant settings are at their default or previously set values The Quit command closes th...

Page 169: ...ed by 1 Hz Only in the receive condition Ctrl X Erases the Transmit or type ahead buffer The PTC acknowledges the command with CLR Ctrl C or Ctrl I Switches the squelch between normal operation and continuously open In normal operation it is possible for even very weak PSK31 signals to open the squelch Switching to continuously open Garbage on the screen even when no PSK31 signal is present should...

Page 170: ...s the final character of a PSK31 transmission A PSK31 transmission can be broken off at any time with the DD command DD sets the system back into the normal STBY mode The PSK31 receive condition can be left by using the Disconnect or Quit command In the PSK31 transmit condition both these commands act as a normal closedown identical to the QRTChr of a transmission The Hot keys have priority in the...

Page 171: ...d only the tone signal is keyed according to the rhythm of the CW characters The special pulse wave shape of the CW character generates a relatively narrow spectrum so that the adjacent PSK31 channels are not disturbed during the CWID The PTC IIIusb sends an additional CWID after a PSK31 transmission if the CWID Parameter refer to CWid chapter 6 27 page 56 is higher than 0 If the parameter is high...

Page 172: ...mple would show the PTC IIIusb RAM expansion cmd SYS Ram Return The sys menu commands in detail 12 1 Audio Serves to carry out a so called Audio loop test or check of the analogue I O stages as well as the DSP This function requires a wire connecting PIN 1 Audio Out and PIN 4 Audio In of the 8 PIN shortwave radio socket X5 If the analogue stages are working correctly the PTC IIIusb gives out OK In...

Page 173: ...mand can contain a command word from the sys menu as argument whereby a description of that command is given Help to the Audio command sys Help Audio Return 12 6 Kill The sub directory killer Enables the stepping through of the PTC mailbox directories in alphabetical order using the and and removing same with the 12 7 Led LED test The PTC IIIusb shows off its lighting console 12 8 PLl Tests the DS...

Page 174: ...m SERNum displays the serial number of the PTC IIIusb This number alwas has 16 digits SERNum answers as follows Serial number 01000005A6E69C22 12 13 Trxtest Tests the transceiver control port This command is only working properly when using a special test adapter on the TRX control connector ...

Page 175: ...Example This command for example would change the frequency of a connected transceiver directly to 14079 0 kHz without having to divert to the trx menu cmd TRX Frequency 14079 0 Return All important TRX parameter are stored in the Flash ROM directly at input and are reloaded with the RESTart command Type Transceiver type baudrate address VFO V24 parameter Parity Parity KType Kenwood type YType Yae...

Page 176: ... not contain essential information it may be omitted The frequency input is always in kHz where however the decimal point after the Megahertz position is optionally allowed e g 14 076 54 The last decimal point is processed as a kilohertz decimal point There are up to three positions allowed after this decimal point whereby a frequency accuracy of 1 Hz has been anticipated which cannot be used by s...

Page 177: ... E T X where denotes in each case one byte ASCII corresponding to 05H 23H 54H 58H 3AH The header is only then valid when it appears complete If for example the third header byte is defective then the PTC IIIusb behaves as if the Ctrl E start character is an accidental Ctrl E or an actual Ctrl E that has not been input as a TRX control character the PTC IIIusb then sending the buffered characters o...

Page 178: ...WOOD or ICOM Transceivers the appropriate end character delimiter is recognized 2 The string length reaches 40 characters That means that the maximum info length of the TRX dump from the PTC IIIusb to the terminal is 40 bytes although with YAESU transceivers the maximum string length is restricted to 19 bytes 3 If no further information is received from the transceiver for longer than 40 byte leng...

Page 179: ...efer to the transceiver manual to switch off the confirmation beep 13 6 Help Gives a short list of the commands used in the trx menu The Help command may also contain a command word from the trx menu as argument whereby a description of that command is given Special information to the Channel command trx Help Channel Return 13 7 KType Default setting 0 Parameter 0 Normal Kenwood protocol 1 Modifie...

Page 180: ...tone frequency must be subtracted in order to find the correct frequency to tune the SSB transceiver to If the Offset value is defined as 1 4 kHz the PTC IIIusb does the required frequency correction for the Mark frequency automatically It is thus only necessary to give the wanted Mark frequency and the correct offset is automatically applied For example one can give the command Frequency 14079 0 ...

Page 181: ...e command 13 14 Scan Default setting 0 Parameter 0 Stop scanner 1 Start scanner C 1 32 toggle channel scan status The Scan command has two different functions If as argument a 1 or 0 follows then that means the scanner is switched on or off respectively This can be said to be the main switch for the scanner If as argument the word Channel Minimum abbreviation C follows then the PTC requires a furt...

Page 182: ...d can be replaced with a space Leading zeros are also optional If the TImer command is given without arguments then the PTC lists the entire timer table If only the timer number is given as argument then the PTC IIIusb shows the times defined for only this timer A single hyphen as a timer period erases the timer E g trx TI 1 Return 13 16 Transfer The command Transfer allows any character sequences...

Page 183: ...0 57600 76800 115200 For NMEA ICOM the given baudrate is ignored and is set to fixed 4800 baud For the third argument differs depending on the selected transceiver type ICOM and NMEA ICOM The PTC requires the ICOM equipment address number The address can be entered decimal 0 to 255 or hexadecimal 0 to FF If entered hexadecimal the has to be entered first same for F0 or 6C Leading zeros are suppres...

Page 184: ...sparently ATTENTION In order that Codan NGT transceivers accept commands at a remote port RS232 15 way or RS232 9 way the CICS command must be activated config menu only after admin login Another very important restriction must be considered Only frequencies that are predefined in a channel within the transceiver can be chosen through the remote port If an exact match cannot be found the channel w...

Page 185: ... Set Scan parameter of channel 4 to YES trx XS 4 1 Return The XScan command is particularly useful in the initialization configuration file of the PTC IIIusb because a new defined state can be set without knowing the current state of the scan parameter 13 20 YType Default setting 0 Parameter 0 YAESU Type FT 890 1 YAESU Type FT 990 FT 1000 2 YAESU Type FT 1000 MP 3 YAESU Type FT 100 4 YAESU Type FT...

Page 186: ...preset in the TRX itself is selected This has the advantage that filter settings and sideband information etc are additionally stored in the TRX and therefore under control of the PTC IIIusb 13 23 Channel attributes The desired channel attribute must be given when setting up the scan channel list in the comment field Here for example it is possible to define at which time the channel shall be acti...

Page 187: ...the time window defined by the T attribute Is this not the case the channel is skipped E g One sets the timer 0 with the TImer command to a time span of 14 00 to 15 00 Command TI 0 14 00 15 00 Enter The attribute T0 then limits the active time of a scan channel to 14 00 to 15 00 If no further TImer attributes are given for this channel then the channel is only scanned between 14 00 and 15 00 At al...

Page 188: ...tly be appended to the hex string without inserting an additional delimiter If an A attribute directly follows the hex string a delimiter must be inserted e g a space character see example trx C 1 3584 00 h0000c3540c a1 Return 13 23 4 Level Attribute With the Level Attribute L2 L2 a channel can be limited to PACTOR 1 2 operation only This can be used if on the dedicated channel PACTOR 3 transmissi...

Page 189: ...sion while the other still contains a part of the old firmware It is very unlikely that such a mixture will run and the Bootloader is then the only way that the update can be repeated The Bootloader is automatically activated as soon as the PTC IIIusb detects an error on loading the PACTOR firmware or the user wishes access to the Bootloader intentionally with activating rear DIP switch 2 14 1 Boo...

Page 190: ...FC Return The flash call is used as default callsign by the PACTOR firmware after a RESTart 14 3 2 FSelcall Default setting none Parameter SELCALL Flash Selcall max 4 characters Checking and setting of the flash selcall By using the FSelcall command it is possible to store your own selcall permanently in FLASH ROM Stores the flash selcall DFCJ cmd FS DFCJ Return Checking the flash selcall cmd FS R...

Page 191: ...sion Displays the version number of the Bootloader 14 4 Bootloader SYStest commands 14 4 1 CHKFlash Check Flash ROM for valid PACTOR firmware 14 4 2 CHKRam Calculate RAM checksum and display in hexadecimal form 14 4 3 Help Displays all useable commands It is also possible to obtain further help on a command whilst in Bootloader mode with Help CMD More details to the RUN command sys Help RUN Return...

Page 192: ... format and the short packet lengths of AMTOR have been retained These result in a protocol much more resistant to interference than Packet Radio under poor propagation conditions The PACTOR protocol together with the SCS PACTOR Controller allows a much higher throughput than AMTOR with the efficient error correction and data transparency of Packet Radio One should not however be under the impress...

Page 193: ...rn hardware and which can be classed as state of the art The main question was what could be improved in PACTOR 1 A bit of head scratching provided the answer First of all a significant improvement has to be done to the working range which requires greater adaptability In practice this means that even extremely weak or disturbed signals should still allow a connection even if they are so bad that ...

Page 194: ...lso incorporated 15 3 Basics of the PACTOR 2 protocol 15 3 1 General The PACTOR 2 protocol PT 2 is essentially based on the Level I standard consisting of a synchronous half duplex ARQ protocol New however is the ability to choose four different speed steps so that a greatly improved adaptability is obtained The modulation system used for PT 2 is based on DPSK differential phase shift keying see b...

Page 195: ...xactly the relationship between bandwidth and the maximum step speed which finally led to his sampling theory Stemming from his work a special step or impulse waveform was found that contained the ideal characteristics for data transmission over an electrical circuit A special version of this waveform with even better characteristics led to the so called raised cosine waveform For insiders the for...

Page 196: ...ake if there are only two possible phase changes between the steps it s called differential binary phase shift keying DBPSK Every step contains exactly one bit of information If four different phase changes are allowed then the modulation is called differential quadrature phase shift keying DQPSK Every step of course then carries two bits of information With eight or sixteen allowable phase change...

Page 197: ...ude HF signal e g PACTOR 2 SSB speech modulation AM etc it is NEVER allowed to overdrive the transmitter because intermodulation products will be generated broaden the signal How to adjust the maximum transmitter power will be described in the PSKAmpl command refer to chapter 6 72 on page 76 It always has to be taken in consideration that with a variable amplitude modulation system the effective a...

Page 198: ...code convolutional codes a number of different methods can be employed The optimum decoder that really can achieve the maximum possible gain from the code is called a Viterbi decoder Unfortunately there is an exponential relation ship between constraint length and the computing time required by a Viterbi decoder This is why the use of the Viterbi decoder for real time tasks has been limited to a m...

Page 199: ... the system does not transmit each character individually instead an sample character is sent followed by the required number of same A few words on how PMC functions would not be out of place here Normal Huffman compression makes use of the statistical frequency distribution of characters in plain language text The characters most used e g e and n are coded with only two or three bits Rare charac...

Page 200: ...ion of the two commands FSKAmpl refer to chapter 6 42 page 62 and PSKAmpl refer to chapter 6 72 page 76 Once that has been done then one is ready to start The transceiver can be tuned to say 3583 7 kHz or 14079 0 kHz and DL2FAK called providing the frequency is clear If there is PT traffic on the chosen frequency irrespective whether PT 1 or PT 2 the PTC IIIusb will automatically copy it providing...

Page 201: ... PACTOR 1 A maximum speed of 140 characters per second can be achieved This is approximately 30 times the effective AMTOR speed Switching between speeds occurs automatically The operator can influence this a little by using the MAXUp and MAXDown parameter as with Level 1 PACTOR The PTC IIIusb not only uses the packet statistics as a switching criterion but also measures the average phase offset fr...

Page 202: ...udio cable PTC 8 pin DIN to ICOM 13 pin DIN e g for M706 IC 718 Order No 8110 YAESU Audio cable PTC 5 pin DIN to YAESU FT 817 6 pin Mini DIN e g for FT 100 FT 817 FT 897 Also usable for 1k2 Packet Radio Order No 8120 KENWOOD Audio cable PTC 8 pin DIN to KENWOOD ACC2 13 pin DIN Order No 8160 2 m Audio extention cable 8 pin DIN socket to 8 pin DIN connector Order No 8140 3 m Audio extention cable 8 ...

Page 203: ...PTC IIIusb to the PC Order No 8030 Bluetooth USB Stick For computers which do not have Bluetooth on board yet Is plugged into a free USB connector on the PC Order No 2370 Shielded cables with molded connectors on one side tinned open ends on the other side pigtail 1 5 meter Cable with 5 pin DIN connector Order No 8010 Cable with 8 pin DIN connector Order No 8020 Cable with 13 pin DIN connector Ord...

Page 204: ...z ROM Max 256 kByte CMOS FLASH ROM for easy updates RAM Static 2 MByte CMOS System monitoring With an internal processor watchdog Front panel Labelled A total of 8 LED s splitted into various functional groups ON OFF Touch sensor switch Rear panel Labelled Input for power supply Socket for connection to the transceiver Socket for transceiver remote control connections GPS connector as 3 wire screw...

Page 205: ...panel D 2 The USB connector The PTC IIIusb is connected to the computer using a type B USB connector Figure D 1 USB connector D 3 Transceiver remote control socket 2 4 3 5 6 7 8 9 13 1 10 11 12 197 Figure D 2 Transceiver remote control Warning Do not interchange the TTL and V24 level connections Pin 1 RxD TTL Pin 2 RTS V24 Pin 3 TXD V24 Pin 4 CTS V24 Pin 5 CTS TTL Pin 6 ICOM Pin 7 Not connected Pi...

Page 206: ...tter PTT line Pin 4 Audio input from the receiver to the PTC loudspeaker or appropriate AUX socket Pin 5 Optional power supply input Pin 6 unused Pin 7 unused Pin 8 unused Figure D 3 Connections to the transceiver The socket outer screening is also connected to ground D 5 GPS Figure D 4 GPS connector The input is compatible with TTL and V24 signals 198 ...

Page 207: ...rown Table D 1 Cable Colors 8 pole DIN cable 5 pole DIN PIN Color 1 Violet 2 White 3 Yellow 4 Green 5 Blue Table D 2 Cable Colors 5 pole DIN cable 13 pole DIN PIN Color PIN Color 1 violet 8 red 2 white 9 pink 3 yellow 10 light blue 4 green 11 black white 5 blue 12 grey 6 black 13 orange 7 brown Table D 3 Cable Colors 13 pole DIN cable ...

Page 208: ...in ASCII American Standard Code of Information Interchange 7 bit code for numbers characters special characters and control characters Backup Another word for safety copies which should be done regularly Very special often created with a lot of work program configurations should be saved regularly too Baudot Code 5 bit code used to transmit characters in RTTY and AMTOR BIOS Bootloader Basic Input ...

Page 209: ... to notice and correct transmission errors without transmitting the information again FIR Finite impulse response Digital filter with finite impulse response Firmware Firmware offering necessary functions to the user e g PACTOR AMTOR RTTY etc including command interpreter and multitasking Therefore often new improved and enlarged versions are available FLASH Special type of ROM which can be progra...

Page 210: ...ompt Using DOS for example the prompt looks like C DOS PSK Phase Shift Keying RAM Random Access memory RMNC The short expression for Rhein Main Network Controller A special hardware especially developed for the use as a digipeater ROM Read Only Memory In the SCS PTC IIIusb a special form of the ROM is used the so called FLASH memory RS232 Standard for the transmission of serial data Defines the pi...

Page 211: ...ard All signals received by the serial interface are displayed on the screen All inputs made at the keyboard are transmitted via the serial interface TTL Transceiver Transistor Logic Integrated circuits completely built up using transistors TTL level Logic level used in TTL circuits Usually 0V for a logical 0 low and 5 V for a logical 1 high are used Tx Short name for transmit TxD Short name for t...

Page 212: ...l mode PACTOR Break In January February 1992 9 ROY PHILPOT DJ0OW PACTOR Here and Now Amateur Radio 12 1992 10 C RICHARDS 9M2CR PACTOR The Magic Successor to RTTY and AMTOR Amateur Radio 3 1993 11 ROY PHILPOT DJ0OW PACTOR The Canadian Amateur Radio Magazine 1992 12 JA5TX PACTOR CQ ham radio 10 1992 13 JA1GGA PACTOR PTC CQ ham radio 2 1993 14 J MEHAFFEY K4IHP PACTOR Phone Home QST 9 1993 15 STEVE FO...

Page 213: ...1 Comment 121 Path 122 Position 122 Short 122 Symbol 123 Timer 123 AQrg 47 AResolut 112 ARX 48 50 Audio 97 161 AUdio 48 Audio functions 43 Audio output level 62 76 AUDPerm 161 Auto status in hostmode 148 Avoid incompatibility 42 B BAKup 48 Bandwidth 97 Basic principles 150 Basics of the PACTOR II protocol 185 Baud 124 BAUdot 49 BC 50 BIOS 179 BIOS and Firmware 179 BKchr 50 BMsg 50 BOOT 51 Box 51 B...

Page 214: ...ell 169 E EQualize 61 Error control coding 188 ESCchr 61 Extended Hostmode 147 F F 138 FAX 62 101 142 FAX and SSTV basics 101 Fax menu command 105 FCall 180 FEc 62 FEC 50 Firmware of the PTC IIIusb 27 Firmware update 92 Fmfax 107 FM FAX 102 Frack 138 FRack 126 Frequency 169 FResolut 112 FSelcall 180 FSK 109 162 FSKAmpl 62 FSKBaud 113 G General Information 101 General points 191 Glossary 200 GPS 38...

Page 215: ...tor 69 MStamp 129 MText 129 MYAlias 129 MYcall 70 130 MYLevel 70 MYMail 130 MYSelc 71 N N 139 NAVTEX 71 NAVTEX area code 72 NAVTEX details 36 NAVTEX general 35 NAVTEX in practice 37 NAVTEX latency 72 NMEA 24 38 76 140 NMEA channel 149 Notch 98 NULl 74 O O 139 Offset 170 Online data compression 190 P P 139 PACket 74 Packet Radio 117 300 baud via HF 110 Baudrate 124 Enabling the mailbox 131 Hostmode...

Page 216: ...lch 82 SResolut 113 SRP 120 SSTV 103 104 107 Start of the CRC hostmode 153 STatus 82 83 84 Status output in hostmode 148 Stuffing errors 152 SYStest 84 161 181 T T 140 Technical Data 195 Term 85 Through 99 TIme 87 Timeout 67 TImer 172 Tips and Tricks 116 TNC 87 TOne 99 TOnes 88 TR 90 TRACE 132 Transceiver control 21 90 165 Transceiver remote control socket 197 Transfer 172 173 Transmission at Mode...

Page 217: ...Index 209 W W 141 Wait 175 Why PACTOR 183 Why PACTOR II 184 Write 94 X XScan 175 XUser 95 Y Y 141 YAESU 757 connection 23 YAESU connection 23 YAESU Transceiver control 176 YType 176 ...

Reviews:

No comments

Brands by name

Popular brands

Load more brands