CCARC - BPRA Ham Basics 2010 ---------- Welcome! Digital Communications “AMATEUR RADIO IS THE HOBBY… EMERGENCY COMMUNICATIONS IS A COMMITMENT…” 1 Ham Basics 2010 K7GJT‐ Digital Communications 2 Subjects to cover • Amateur Radio Digital Mode History • Two Basic Digital Technologies • TNC Technology, Modes & Software • Soundcard Technology, Modes & Software • Accuracy • Making the connection without wires • Making the connection with wires • Dig ita l MiMessaging Systems • Making the “over‐the‐air” connection with radio Ham Basics 2010 K7GJT‐ Digital Communications 3 Amateur Radio Digital Mode History • The ‘Original Digital’ mode – Presence or absence of carrier (1, 0, 1, 0, 1, etc.) – CW! Ham Basics 2010 K7GJT‐ Digital Communications 4 Amateur Radio Digital Mode History • Started as Mechanical Hardware Specific – 1849 Landline based teleprinter operations began – 1920 Rudolf Hell invented Hellschreiber – 1930’s RTTY (Radio TeleTYpp)e) [y[Military RATT/]/SCRT] • 1980’s started computerizing the RTTY signals • Prior to 1995 the only ‘legal’ HF digital mode that was authorized by the FCC were those that used the standard Baudot codes; ege.g. RTTY Ham Basics 2010 K7GJT‐ Digital Communications 5 Amateur Radio Digital Mode History • In 1995, the FCC opened to door to other modes (ASCII based) and declared that any new mode coding were legal as long as they were published in the public domain. • And the “Barn Door” opened! Ham Basics 2010 K7GJT‐ Digital Communications 6 Amateur Radio Digital Modes Ham Basics 2010 K7GJT‐ Digital Communications 7 Two Basic Digital Technologies • Objective is “Tones‐to‐Digits‐to‐Tones” • Terminal Node Controller (Hardware based) – External ‘smart b’box’ converter for dig its‐to‐tones‐ to‐digits – NtNot iiinexpensive • Soundcard (Software based) – External or Internal PC microprocessor converter for digits‐to‐tones‐to‐digits Ham Basics 2010 K7GJT‐ Digital Communications 8 Digits‐to‐Tones‐to‐Digits Ham Basics 2010 K7GJT‐ Digital Communications 9 TNC Technology • TNC (Terminal Node Controller ) – Typically external to PC – Many mfg’s (SCS, Kantronics, Timewave/AEA, etc.) – Some have Digital Signal Processing (DSP) built‐in Ham Basics 2010 K7GJT‐ Digital Communications 10 TNC Modes • PACTOR I, II, III • AMTOR • RTTY • PSK31 • CW • PACKET (HF & U/VHF • NAVTEX • TDM Ham Basics 2010 K7GJT‐ Digital Communications 11 TNC Software Generic SCS Specific • Alpha • NCWinPTC • PCPakRatt • NCWinPTC Term • Airma il • ETEzTrans fer – PACKET/PACTOR • SCS Mail • Paclink – PACKET/PACTOR • RMS Express – PACKET/PACTOR Ham Basics 2010 K7GJT‐ Digital Communications 12 External TNC Devices Ham Basics 2010 K7GJT‐ Digital Communications 13 Soundcard Technology • Soundcard – Internal to PC – External to PC (Tigertronics, WMR, etc.) Ham Basics 2010 K7GJT‐ Digital Communications 14 Some Acronyms Defined • AFSK – Audio Frequency Shift Keying • BPSK ‐ Binary Phase Shift Keygying • FSK – Frequency shift Keying • MPSK ‐ Multiple Phase Shift Keying • QPSK ‐ Quadrature Phase Shift Keying Ham Basics 2010 K7GJT‐ Digital Communications 15 Soundcard Modes • BPSK 31/63/125 • MFSK 8/16 • SSTV • QPSK 10/31/50 • OLIVIA • MT‐63 • MPSK • THROB • CHIP • PACKET • Domino • APRS • CCW • PAX • Contestia • PACTOR 1 • ALE • HF FAX • AMTOR FEC • COQUELET • WIMOR • RTTY • Hellschreiber Ham Basics 2010 K7GJT‐ Digital Communications 16 Soundcard Software • Cwtype • MT63 • SlowFel • DIGIPAN • MultiPSK • SlowFeld • DigTRX • NBF • Stream • Feld Hell • PacLink • Throb • FTV • Paxon • TrueTTY • Hamscope • PcPakratt • W1SQLPSK • JVComm32 • RDFT • WinDRM • MixW • RMS Express • WinPack • MMSSTV • Sally • WinPSKse • MMRTTY • SCAMP • WSJT Ham Basics 2010 K7GJT‐ Digital Communications 17 MixW Ham Basics 2010 K7GJT‐ Digital Communications 18 MultiPSK Ham Basics 2010 K7GJT‐ Digital Communications 19 External Soundcard Devices Ham Basics 2010 K7GJT‐ Digital Communications 20 Accuracy • Broadcast Mode – Character loss is not important • Error Checking modes – ARQ (Automatic Repeat‐reQuest) – FEC (Forward Error Correction) Ham Basics 2010 K7GJT‐ Digital Communications 21 Accuracy • The ARQ mode is used where absolute accuracy is paramount on the exchanged message. – It uses a handshaking technique to ensure absolute accuracy in the exchange of data. – When a block of the message is not received with 100% accuracy, the receiving station requests the entire bloc k to be resent. Ham Basics 2010 K7GJT‐ Digital Communications 22 Accuracy • The FEC mode is used where absolute accuracy is not paramount but a higher degree of message exchange reliability is. – A redundant data transmission technique that transmits the information using a predetermined algorithm (no handshaking) Ham Basics 2010 K7GJT‐ Digital Communications 23 Mode Displays AMTOR CW FAX HELLSCREIBER Ham Basics 2010 K7GJT‐ Digital Communications 24 Mode Displays FSK31 MT-63 (1000HZ) PACTOR 1 PACTOR 2 PACTOR 3 PSK 31/63/125 Ham Basics 2010 K7GJT‐ Digital Communications 25 Mode Disppylays SSTV THROB VHF PACKET Ham Basics 2010 K7GJT‐ Digital Communications 26 Making the connection without wires Receive =Radio Speaker ‐ into ‐ Computer Microphone Transmit = Radio Microphone –into – Computer Speaker Ham Basics 2010 K7GJT‐ Digital Communications 27 Making the connection with wires Ham Basics 2010 K7GJT‐ Digital Communications 28 Soundcard Interface ‐ Improved • Two issues 1. TX & RX Audio isolation 2. PTT control Note: Buxcomm Product Shown Ham Basics 2010 K7GJT‐ Digital Communications 29 Digital Messaging Schemes 1. Keyboard‐to‐Keyboard – Type message on keyboard 2. Station‐to‐Station (Point‐to‐Point) – Typed or text file message “Mailboxes” (MBX) 3. Local Message Boards (BBS) – Central location for formatted messages 4. Wide Area StSystems – Winlink 2000 (input/output via a ‘RMS’) Ham Basics 2010 K7GJT‐ Digital Communications 30 Digital Messaging Systems • Point‐to‐Point • PACKET – BBS • Winlink 2000 – TELNET – PACKET – PACTOR – WINMOR Ham Basics 2010 K7GJT‐ Digital Communications 31 PACKET System Topology Ham Basics 2010 K7GJT‐ Digital Communications 32 Making the connection with Radio • Point‐to‐Point: Any mode, many softwares • PACKET – AX.25 technology • Winlink 2000 – TELNET – PACKET – PACTOR – WINMOR (WINlin k Message Over Radio Ham Basics 2010 K7GJT‐ Digital Communications 33 Digital Communication • Clark County PACKET – 144.99 [& 441.060] – Station to Station (K‐K or MBX) – Mt Livingston BBS • ClCurrently W7AIA‐8 • Changgging to K7CLL‐8 Ham Basics 2010 K7GJT‐ Digital Communications 34 OutpostPM Ham Basics 2010 K7GJT‐ Digital Communications 35 Digital Comms ‐ PACKET Ham Basics 2010 K7GJT‐ Digital Communications 36 Digital Communication • Clark County Winlink 2000 – 144.920 & 441.525 – VHF: K7YFJ‐10 & KA7CTT‐10 – UHF: K7YFJ‐10 & K7GJT‐10 Ham Basics 2010 K7GJT‐ Digital Communications 37 Winlink 2000 Toppgyology Radio Message Server T ELNET The Internet “Cloud” Common USER TELNET TELNET Message AIRMAIL Server PACLINK RMS Express Connected to Client PCs or Network! K7GJT‐ Digital Communications 38 Winlink Station Ham Basics 2010 K7GJT‐ Digital Communications 39 RMS Express & Paclink Ham Basics 2010 K7GJT‐ Digital Communications 40 Airmail Ham Basics 2010 K7GJT‐ Digital Communications 41 Digital Comms – WL2K RMSs Ham Basics 2010 K7GJT‐ Digital Communications 42 • Amateur PACKET Reporting System – “Maps and Messaging” – Over 40,000 users – Most common use is position reporting – Weather – Telemetry • Covered in next Session Ham Basics 2010 K7GJT‐ Digital Communications 43 Questions? Ham Basics 2010 K7GJT‐ Digital Communications 44.