1. Radio in the Digital Age Steven F. Goldberg, W3SFG

2. Part 1: Internet Operating Aids Part 2: Survey of Digital Operating Modes Part 3: Internet Resources and Databases Part 4: Software Applications http://w3sfg.net/resources/ 15 October 2012Radio in the Digital Age2 Radio in the Digital Age Series Outline

3. Radio in the Digital Age Part 2: Digital Operating Modes Steven F. Goldberg, W3SFG 15 October 2012 Radio in the Digital Age315 October 2012

4. Where I Started 15 October 2012Radio in the Digital Age4

5. Computer encode / decode No Morse Code to learn Weak signal detection Low bandwidth Error correction Data transfer Mic shy / poor conversationalist Why Digital Modes? 15 October 2012Radio in the Digital Age5

6. Live Keyboard to Keyboard QSO Scripts / Macros – “Recorded” text (e.g. equipment, location) – Custom greetings (with integrated data) – Contest exchanges Data – APRS – Email – DX Spots Content 15 October 2012Radio in the Digital Age6

7. Amplitude Shift Keying (ASK): represents digital data as variations in the amplitude of a carrier wave (e.g. CW) Frequency Shift Keying (FSK): digital information is transmitted through discrete frequency changes of a carrier wave – Binary FSK (BFSK): paired frequencies (0 = “space” and 1 = “mark”) – Multiple FSK (MFSK): uses an "alphabet" of M tones – Audio FSK (AFSK): frequency shifted by transmitted audio tone Phase Shift Keying (PSK): conveys data by changing, or modulating, the phase of a reference signal (the carrier wave) – Binary PSK (BPSK): uses two phases which are separated by 180° – Quadrature PSK (QPSK): uses 4 phases, encoding 2 bits per symbol Orthogonal Frequency Division Multiplexed (OFDM): 64 parallel signals Modulation Types 15 October 2012Radio in the Digital Age7

8. Digital Mode Characteristics 15 October 2012Radio in the Digital Age8 TypeMode Symbol Rate (Baud)WPM Width (Hz) Error Correct Duty Cycle ITU DesignationCoding ASKCW-10050100200No44%200H0A1AMorse ASKCW-20102050No44%50H0A1AMorse ASKFELD-HELL12325350No22%350HA1BNone FSKRTTY-454560270No100%270HF1BBaudot FSKRTTY-7575100370No100%370HF1BBaudot MFSKContestia 8-2503130250Yes100%250HF1BASCII-128 MFSKDominoEX111180262Yes/No100%262HF1BASCII-256 MFSKJT65 MFSKMFSK8836316Yes100%316HF1BASCII-256 MFSKOlivia 8-2503115250Yes100%250HF1BASCII-128 MFSKTHOR111140262Yes100%262HF1BASCII-256 MFSKTHROB222072No80%72H0F1B44 Chars OFDMMT63-500550500Yes80%500HJ2DENASCII-128 PSKBPSK-31315062No80%63H0G1BASCII-256 PSKBPSK-6363100125No80%125HG1BASCII-256 PSKQPSK-31315062No80%63H0G1BASCII-256 PSKQPSK-6363100125No80%125HG1BASCII-256

9. Radio Teletype (RTTY) 15 October 2012Radio in the Digital Age9 Established FSK mode / Keyboard to Keyboard 5 bit Baudot-Murray code represents all letters and numbers + some punctuation (“00100” = space, “00001” = E, “01010” = R); shift between numbers / letters 45 baud (most common mode) corresponds to a typing speed of 60 WPM 50 baud / 75 baud also in use No error correction; QRM/QRN/QSB degrade Many modern HF rigs have RTTY capability / some decode signal AFSK emulation with sound card interface Popular contesting mode (e.g. CQ-WW-RTTY, ARRL RTTY Roundup)

10. Facsimile image transmission Feld Hell most common for HF, uses ASK (on/off keying) to create images Text characters are "painted" on the screen, as apposed to being decoded and printed Activity centered on special FH events, scheduled QSOs FELD HELL / HELLSCHREIBER 15 October 2012Radio in the Digital Age10

11. Multi-frequency shift keyed (mode with low symbol rate A single carrier of constant amplitude is stepped between frequencies Full-time forward error correction(sends all data twice) Requires precise frequency alignment Designed for long-path DX Relatively wide bandwidth (316 Hz) allows faster baud rates (typing is about 42 WPM) and greater immunity to multi path phase shift Numerous variants (symbol rate, modulation) MFSK8 15 October 2012Radio in the Digital Age11

12. MT63 is an Orthogonal Frequency Division Multiplexed (OFDM) mode consisting of 64 parallel carriers each carrying part of the transmitted signal. Highly redundant forward error correction Very robust – compensates for QRM/QRN/QSBto its legendary Relatively wide bandwidth Requires more computer processing power for signal generation / decoding MT63 15 October 2012Radio in the Digital Age12

13. Binary phase shift keying ASCII-256 user interface is used Narrow bandwidth: less than CW, up to 80 PSK31 signals in bandwidth of 1 SSB signal Weak signal / QRP mode Assuming 500 Hz CW filter, may achieve similar S/N at receiver with 1/15 th power Multiple simultaneous software decode PSK Reporter provides propagation information Extremely popular for keyboard to keyboard QSOs Numerous contesting opportunities (B)PSK-31 15 October 2012Radio in the Digital Age13

14. JT65 15 October 2012Radio in the Digital Age14 Developed by K1JT, as part of WSJT for EME and troposcatter QSOs Capable of decoding signals below the noise floor Structured transmissions begin #:01.0 / end #:47.8 – precise clock synchronization required Each frame conveys 72 bits of information + 306 additional bits of forward error correction, using MFSK (65 tones) Weak signal mode – 30 watts is considered high power! Typical QSO: – CQ K1JT FN20 – K1JT W6DTW CM97 – W6DTW K1JT -18 – K1JT W6DTW R-16 – W6DTW K1JT RRR – K1JT W6DTW 73 – W6DTW K1JT 73

15. JT65 QSO 15 October 2012Radio in the Digital Age15

16. Digital Frequencies 15 October 2012Radio in the Digital Age16 BandDigitalPSKJT65 10 Meters28.110 – 28.12528.12028.076 12 Meters24.920 – 24.93024.920 15 Meters21.060 – 21.09021.07021.076 17 Meters18.100 – 18.11018.100 18.102 18.106 20 Meters14.065 – 14.09014.07014.076 30 Meters10.130 – 10.14510.142 10.139 10.147 40 Meters 7.030 – 7.040 7.060 – 7.080 7.035 7.039 7.076 80 Meters 3.575 – 3.585 3.620 – 3.640 3.5803.576

17. Modern transceiver (with rig control [CAT/CI-V]) Sound card interface – Tigertronics – West Mountain Radio – MFJ Enterprises – Buxcom Computer – Windows / Mac OS / Linux / Android / iOS – Some transceivers have encode / decode capability Getting on the Air 15 October 2012Radio in the Digital Age17

18. Software (many are freeware) – Ham Radio Deluxe / DM780 – WinWarbler – Digipan – MixWMultiPSK – FLDigi – Hamscope – WSJT – Winklink – JT65-HF – MMTTY Getting on the Air 15 October 2012Radio in the Digital Age18

19. CW/Digital Go Kit 15 October 2012Radio in the Digital Age19

20. WSPR V4 Chat APRS Pactor / Amtor SSTV Other Modes 15 October 2012Radio in the Digital Age20

21. http://www.w1hkj.com/FldigiHelp-3.20/Modes/index.htm – Digital Modes – Sight and Sound (descriptions of various modes)i– http://wb8nut.com/digital/ – WB8NUT Digital Modes Information Page http://www.w4cn.org/about-ham-radio/digital-modes – Amateur Radio Transmitting Society of Louisville, Kentucky – Digital Modes http://wiki.ham-radio-deluxe.com/index.php?title=DigitalSignals – The Sights and Sounds of Digital Modes http://www.arrl.org/tis/info/HTML/psk31/index.html – PSK31 information http://www.qsl.net/ws1sm/digital.html – Wireless Society of Southern Maine – Digital Modes http://winlink.org/ – WinLINK information INTERNET RESOURCES 15 October 2012Radio in the Digital Age21

22. 15 October 2012Radio in the Digital Age22