Introduction to Packet Radio
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DIGITAL COMMUNICATIONS by AD5XJ Ken LA Section Technical Specialist
DIGITAL COMMUNICATIONS by AD5XJ Ken LA Section Technical Specialist Disclaimer: These are my comments on digital communications and are not necessarily all there is to know on the subject. As with everything computer related – there are at least six ways to do the same thing. Given this caveat, let me say this is opinion and not the complete story. I only relate to you my experience of 5 or more years using digital modes to give you the benefit of my experience. I will leave the rest for you to research as you see fit. Digital Sound Card Software: In an effort to make sense of the vast selection of software available to ham operators, this session will be devoted to supplying information to help you in deciding what software will best suit your application. Selection of software is highly subjective in that it depends almost entirely on the operator and situation as to which software is appropriate or useful. What we attempt to do here is give the capabilities of software on a comparative basis and allow you to make those choices as needed. We will group the available applications into three basic catagories: 1) digital text, 2) digital voice, 3) digital image and video. All software applications mentioned can be used with the computer soundcard as the modem. Some also allow the use of external computer sound interfaces like the Tigertronics SignaLink modem which has a soundcard built in and does not rely on the soundcard in the computer. Offloading the soundcard duties in this manner increases the efficiency of the interface function several orders of magnitude given the modest cost of $99-$125. -
Winwarbler 7.9.2
WinWarbler 7.9.2 Overview .....................................................................................................................................................................2 Prerequisites ...............................................................................................................................................................3 Download and Installation ..........................................................................................................................................4 Configuration ..............................................................................................................................................................5 General Settings .........................................................................................................................................................7 Display Settings ....................................................................................................................................................... 10 Push-to-talk (PTT) Settings ..................................................................................................................................... 13 Soundcard Settings ................................................................................................................................................. 15 Configuring Multiple Soundcards ............................................................................................................................. 16 Phone Settings -
Technical Handbook for Radio Monitoring HF
Technical Handbook for Radio Monitoring HF Edition 2013 2 Dipl.- Ing. Roland Proesch Technical Handbook for Radio Monitoring HF Edition 2013 Description of modulation techniques and waveforms with 259 signals, 448 pictures and 134 tables 3 Bibliografische Information der Deutschen Nationalbibliothek Die Deutsche Nationalbibliothek verzeichnet diese Publikation in der Deutschen Nationalbibliografie; detaillierte bibliografische Daten sind im Internet über http://dnb.d-nb.de abrufbar. © 2013 Dipl.- Ing. Roland Proesch Email: [email protected] Production and publishing: Books on Demand GmbH, Norderstedt, Germany Cover design: Anne Proesch Printed in Germany Web page: www.frequencymanager.de ISBN 9783732241422 4 Acknowledgement: Thanks for those persons who have supported me in the preparation of this book: Aikaterini Daskalaki-Proesch Horst Diesperger Luca Barbi Dr. Andreas Schwolen-Backes Vaino Lehtoranta Mike Chase Disclaimer: The information in this book have been collected over years. The main problem is that there are not many open sources to get information about this sensitive field. Although I tried to verify these information from different sources it may be that there are mistakes. Please do not hesitate to contact me if you discover any wrong description. 5 6 Content 1 LIST OF PICTURES 19 2 LIST OF TABLES 29 3 REMOVED SIGNALS 33 4 GENERAL 35 5 DESCRIPTION OF WAVEFORMS 37 1.1 Analogue Waveforms 37 Amplitude Modulation (AM) 37 Double Sideband reduced Carrier (DSB-RC) 38 Double Sideband suppressed Carrier (DSB-SC) 38 Single Sideband -
Replacing 1200 Baud AFSK FM with PSK and Deploying DTN Iain Young [email protected]
Replacing 1200 Baud AFSK FM with PSK and Deploying DTN Iain Young [email protected] Agenda ● Introductions ● AX.25 Link Established! ● Exactly What Are We ● Adding TCP/UDP/IP Planning To Replace ? ● Adding DTN ● Why Replace It ? ● Results ● Computer Network Theory ● Conclusions ● How We Replaced It ● Future Experiments – Tools and Utilities Needed ● Acknowledgements – RF Setup and Maps Introductions ● Two major areas of focus – Replacing AX.25 1200 baud AFSK FM with PSK – Deploying DTN ● Who ? – Iain Young, G7III, MAXPAK Chairman – Dave Madew, M0DCM, MAXPAK Committee Member ● MAXPAK – Formed as a dedicated AX.25 Packet group for the Midlands – Constitution changed a couple of years ago, to include all digital modes So What Are We Replacing, And What Are We Not Replacing ? ● The AX.25 Physical Layer – In “Network” Parlance, Layer 1 – We mean the 1200 baud AFSK FM transmissions ● We are not replacing what the network world would call “Layer 2” or “The Data Link Layer” where you send and receive AX.25 frames to and from AX.25 addresses ● The mode we are all familiar with could be more formally described as AX.25 over 1200 baud AFSK FM ● The mode we will be creating could be more formally described as AX.25 over PSK Why Do This ? (1) ● 1200 baud AFSK FM is not exactly well known for it's effeciency, especially with regards to: – Spectrum usage, – Power requirements – Link budget ● Even it's 300 baud cousin is not particularly well thought of on HF, can be improved on and that's only a quarter the throughput! Why Do This ? (2) ● Plenty have claimed -
Overview of Ham Radio Software
OVERVIEW OF SOFTWARE FOR DIGITAL HAM RADIO Where to download free software: (often there are helpful help files also, so you might want to peruse around a bit more than just download) FLDIGI https://sourceforge.net/projects/fldigi/files/fldigi/fldigi- 3.23.15_setup.exe/download https://sourceforge.net/projects/fldigi/files/fldigi/ Downloading FLDIGI can be a bit tricky. Try going to the above page and then selecting (for Windows) the file ending with “setup.exe”. WINLINK EXPRESS http://www.winlink.org/sites/default/files/downloads/winlink_express_insta ll_1-4-2-0.zip UZ7HO http://uz7.ho.ua/modem_beta/soundmodem95.zip is the actual download. SOUNDMODEM.EXE WINDOWS BPQ http://www.cantab.net/users/john.wiseman/Downloads/LastestInstaller/ is the directory http://www.cantab.net/users/john.wiseman/Downloads/LastestInstaller/BPQ 32_6.0.13.1_20160927.exe is the actual download link Malware Detection Software: Many commercial virus checkers and malware detectors will consider very rare software to be automatically suspect, and delete or refuse to run or load it. You will have to find out how to tell your malware detection software to accept these quite- respectable programs. Every malware detection program works differently, so read your instructions! Digital Ham Radio has many facets. Characters from a computer become some version of “tones” going to a transmitter microphone input; audio from a receiver speaker output gets transformed into characters in a computer and possibly visible on the screen to a user. Software & hardware combine to make this magic happen. This paper will attempt to categorize the major software required to accomplish several communications. -
The LANDLINE the Newsletter of the COPPER COUNTRY RADIO AMATEUR ASSOCIATION, INC
Volume 24 Number 01 January 2007 The LANDLINE The Newsletter of the COPPER COUNTRY RADIO AMATEUR ASSOCIATION, INC. P.O. BOX 217 DOLLAR BAY, MICHIGAN 49922-0217 Visit us on the World Wide Web: www.ccraa.net Membership:”Time to Join or Renew” 2007 CCRAA membership form is available via the Web page at http://www.ccraa.net/start.html. Also attached form with this issue of CCRAA newsletter. Howard(KD8ABP) FOR SALE: Wilson tri-band beam $80. Also, all books going for 50% off. Contact: Stanley F. Strangle, K8NYT at Bruce Crossing, MI (906) 827-3526 or (906) 390-3526 (cell phone) Web-Site: The below web address was provide by Gary(K8YSZ) www.rfcafe.com. PROGRAM FOR JANUARY: A program on the FCC's WT Docket 04-140 (Omnibus Band Plan), and their WT Docket 05-235 (Dropping the Morse code) will be presented by Geo., W8FWG * AO-51 "Echo" is now carrier-access: AO-51 "Echo" satellite users no longer need to transmit a 67-Hz CTCSS subaudible tone to enable the satellite's transponder. AMSAT Vice President of Operations Drew Glasbrenner, KO4MA, reports AO-51 is now a carrier-access satellite. The change was aimed at improving worldwide access to AO-51, especially from those areas where CTCSS-equipped transceivers are less common. Check the AO-51 operating schedule <http://www.amsat.org/amsat- new/echo/ControlTeam.php> *before* using the satellite! -- AMSAT News Service HAMFEST: Michigan, Negaunee (FEB 3) Flea Market,Dealers/Vendors 9am-1pm Hiawatha ARA, Negaunee Township Hall, 42 Hwy M-35. Swap & Shop, Refreshments, TI 147.270 (100Hz) Adm:$4, Tables:$6 POC: Robert Serfas, N8PKN, 1600 Bayview Dr., Marquette, MI 49855; 906-225-6773; [email protected]; www.qsl.net/k8lod/. -
16.1 Digital “Modes”
Contents 16.1 Digital “Modes” 16.5 Networking Modes 16.1.1 Symbols, Baud, Bits and Bandwidth 16.5.1 OSI Networking Model 16.1.2 Error Detection and Correction 16.5.2 Connected and Connectionless 16.1.3 Data Representations Protocols 16.1.4 Compression Techniques 16.5.3 The Terminal Node Controller (TNC) 16.1.5 Compression vs. Encryption 16.5.4 PACTOR-I 16.2 Unstructured Digital Modes 16.5.5 PACTOR-II 16.2.1 Radioteletype (RTTY) 16.5.6 PACTOR-III 16.2.2 PSK31 16.5.7 G-TOR 16.2.3 MFSK16 16.5.8 CLOVER-II 16.2.4 DominoEX 16.5.9 CLOVER-2000 16.2.5 THROB 16.5.10 WINMOR 16.2.6 MT63 16.5.11 Packet Radio 16.2.7 Olivia 16.5.12 APRS 16.3 Fuzzy Modes 16.5.13 Winlink 2000 16.3.1 Facsimile (fax) 16.5.14 D-STAR 16.3.2 Slow-Scan TV (SSTV) 16.5.15 P25 16.3.3 Hellschreiber, Feld-Hell or Hell 16.6 Digital Mode Table 16.4 Structured Digital Modes 16.7 Glossary 16.4.1 FSK441 16.8 References and Bibliography 16.4.2 JT6M 16.4.3 JT65 16.4.4 WSPR 16.4.5 HF Digital Voice 16.4.6 ALE Chapter 16 — CD-ROM Content Supplemental Files • Table of digital mode characteristics (section 16.6) • ASCII and ITA2 code tables • Varicode tables for PSK31, MFSK16 and DominoEX • Tips for using FreeDV HF digital voice software by Mel Whitten, KØPFX Chapter 16 Digital Modes There is a broad array of digital modes to service various needs with more coming. -
35 Downlink 2003 Spring
NCPA Downlink The Official Journal of the Northern California Packet Association Serving Amateur Radio Digital Communications in Northern California Spring, 2003 Issue number 35 $2.50 President’s Message News from the ARRL Gary Mitchell, WB6YRU From The ARRL Letter, August 8, 2003 In This Issue Here’s the Spring issue... in early LEAGUE DOCUMENTS DIGITAL President’s Message . 1 September <ahem>. Hopefully we’ll MODES ARRL News . 1 have the Summer issue out while it’s Packet Layers for the still summer. With a new Web page on digital mode specifications, ARRL hopes to make ISO/OSI and TCP/IP In the last issue, a first draft of the answering the question "Is that mode Network Models . 2 proposed “big change” to the bylaws legal?" a lot easier. DX Spotting nodes . 3 (and hence the structure of the The Layperson’s Guide organization) was published. So far, Until 1995, the only permissible digital to High Speed Amateur only one comment was made–and that modes under Part 97 rules were RTTY was only after directly requesting a and modes that used ASCII codes. On Packet Radio . 4 comment. Apparently, no one has any November 1 of that year, the Packet BBS’s . 4 FCC--acting on an ARRL strong feelings one way or the other. Is Digital Channels . 7 that really true? A major structural petition--agreed to allow the use of any change to the organization like this digital mode, providing its technical should spark at least some debate. characteristics were "publicly If you have anything to say about documented"--§97.309(a)(4)--and the HF seemed to be the best way of letting the restructuring the NCPA or the bylaws, digital mode explosion began in earnest. -
Digital Mode Presentation
Digital Mode Presentation General Knowledge Digital communication is the exchange of digital data over the air • Email, Digital files, Keyboard-to-keyboard (chat), and others Protocols on today’s menu • RTTY, PACTOR, JT9/65, PSK31, FSQCall, Olivia Communication = digital mode if info is exchanged as individual characters encoded as digital bits. Example: A = ASCII 01000001 Some consider CW a digital mode. (an A = di-dah) Some modes are old, like radio-teletype, invented in the 1930’s. Some modes are new, like FSQ, invented in the mid-2015’s. Where? • Look at an amateur band chart (80 meters and 20 meters) • Look at a band plan (2-4, 2-17, 6-2) • Show CW, PSK31 (3.570 & 14.070) and RTTY • Look at http://bandplans.com Definitions Air Link – the part of the communication system involving radio transmissions and reception of signals. Bit – fundamental unit of data; a 0 or 1 in binary Bit rate – number of bits per second sent from one system to another. Symbol – signal characteristics that make up each distinct state of the transmitted signal • CW symbols = on and off • RTTY symbols are tones • Baudot or ASCII (simple methods) encode one bit in each symbol • Sophisticated codes use complex audio signals to carry the data and encode more than one bit in each symbol Baud – number of symbols per second that are sent from one system to another. Duty cycle – ratio of transmitting to total on/off time • Important to know duty cycle of mode because most transmitters are not designed to operate at full power for extended periods of time. -
Introduction to Ham Radio Digital Modes Including FT8
Introduction to Ham Radio Digital Modes Including FT8 Steve Ikler, KS3K October, 2018 Some slides and information in this presentation are used with permission from Dave LeVasseur, N0DL and the Lake Area Radio Klub (SD) Methods of Ham Radio Communication • CW (Morse Code) • Voice (SSB, FM, AM, Digital Voice) • Digital (binary, either on or off) – Uses computers, sound cards and software – Converts text messages into audio – The audio gets transmitted – Translates audio back into readable text Why Use Digital Modes • Efficient use of bandwidth • Efficient use of power • Even small, indoor or compromise antennas work well • Still usable when voice or cw cannot be heard • Very popular worldwide • Work DX with minimal station • Foreign accents not a problem – it’s all text • Can send images (SSTV, Winlink) Examples of Digital Modes • CW • RTTY (FSK and AFSK) • PSK (BPSK, QPSK, PSK31, PSK63, PSK125) • *-TOR (Amtor, Pactor, G-Tor, etc.) (Packet) • JT-Modes (Joe Taylor, K1JT) – JT65, JT9, WSPR, MSK144, FT8 • Others – Olivia, CONTESTIA, Feld Hell, MFSK, MT63 What Do You Need • Transceiver • Computer (Laptop/Desktop) • Audio Interface between computer and radio • Software http://www.tigertronics.com/ http://www.westmountainradio.com/ Digital Software • Ham Radio Deluxe (DM780) (Not Free) • Fldigi • WinWarbler (DXLabs) • WSJT-X • RMS Express (Winlink) • MMTTY • MixW Summary of PSK Former King-of-the-Hill • Phase-Shift Keying - Changes (modulates) the phase of a constant frequency reference signal (the carrier wave) • Also used by Wireless LANs, RFID, Bluetooth • BPSK and QPSK – Binary Phase-Shift Keying and Quadrature Phase-Shift Keying • BPSK much more popular • Conversational Mode – Instant Messaging without the internet Summary of FT8 • FT8 is named after its developers, Steven Franke, K9AN, and Joe Taylor, K1JT. -
December 2006
THE OHM TOWN NEWS Voice of the Bridgerland Amateur Radio Club December 2006 >>>>>>>> http://www.barconline.org <<<<<<<< PRESIDENTS MESSAGE HAM PROFILE Here it is, my last presidents message as Presi- by Boyd Humpherys W7MOY dent of the Bridgerland Amateur Radio Club. It is hard to believe that 3 years have past. It has been a lot of Perhaps it’s not often that we use Amateur Ra- work but also a lot of fun. I had a lot of ideas when I dio to report a problem out on the Indy 500 called the took office 3 years ago, but really only one goal. That interstate, however when we have to report our own problem, that’s when it pays off. Kevin Johnson, was to have fun with amateur radio. Fun I have had, M but it is a lot of work to be the president. KD7MHA, did just that. About three years ago on a jaunt down to the big city in mid winter, some strange e I would like to r thank everyone who has quirk of nature had turned I-15 into an ice rink near r helped move the club Farmington. After flawlessly executing a couple of pir- y along these past few ouettes and a full gainer, Kevin found himself off the C years. Thanks to Ted road, thankfully with no injuries. An emergency call to h McArthur, Tammy Ste- a fellow ham on frequency gave the requested call to an r i vens, Tom Baldwin, Ken understanding Pater, another one to the appropriate in- s t Buist, Dave Fullmer , and terested parties, and the rescue procedure got under m Jacob Anawalt for every- way. -
GENERAL CLASS Chapter 6.1~6.6 Digital Modes
GENERAL CLASS Chapter 6.1~6.6 Digital Modes Chapter 6 Digital Modes 6.1 Intro to Digital Modes 6.2 Digital Basics 6.3 Character-Based Modes 6.4 Packet-Based Modes 6.5 Receive & Transmit Digital Modes 6.6 Digital Operating Procedures 1 6.1 Introduction to Digital Modes page 6-1 ∗ Digital communications modes exchange information using individual characters encoded as digital bits . ∗ “A” using CW is “di dah” ∗ “A” using ASCII is “01000001” ∗ Digital communications consists of two basic steps • Information encoding [FCC – 97.309] • Modulation formats ∗ Examples of Digital Communications Modes • RTTY, Packet (VHF/UHF), PSK31, JT-65/JT-9/FT-8/JS-8 …. Keyboard • PACTOR,WINMOR , Winlink…. Email and messaging • DSTAR (ICOM), System Fusion (Yaesu), AOR digital voice, WinDRM, FreeDV …. Voice via digital methods2 6.1 Introduction to Digital Modes page 6-1 ∗ Digital nodes are restricted to CW/Data segments of the HF bands • Usually found at the top end of the CW segment • Band plans define where digital modes may be found • Calling frequencies are typically at the lower end of the band and activity moves up with increased activity [G2E04, G2E08] ∗ 20 Meter band examples for digital mode operating frequencies • PSK-31 – 14.070 MHz; JT-65 – 14.076 MHz; JS8Call – 14.078 MHz • RTTY – 14.080 MHz ∗ Digital Modes are limited in the maximum data rates and signal bandwidths [FCC – 97.307] ∗ Information encoding and signal transmission protocols must be defined by FCC rules or be a publicly available method. ∗ Digital recording of Modes – http://www.kb9ukd.com/digital 3 6.1 Band Plan page 6-1 ∗ Table 6.1 Digital Signal Band Plan [G2E07] 4 6.1 Digital Mode Overview page 6-2~3 ∗ Radioteletype (RTTY ) sound similar to fax machine sound ∗ RTTY pronounced “ritty” is the original mode designed to copied and printed off the air by a mechanical teletype device.