Presentation on theme: "17 July 2014 Introduction to Digital DXing Dennis Egan W1UE Ed Muns W0YK."— Presentation transcript:
17 July 2014 Introduction to Digital DXing Dennis Egan W1UE Ed Muns W0YK
2 of 20 Dennis Egan W1UE Dennis has operated RTTY as W1UE/6Y5, W1UE/VP2E and W1UE/HR9. He has been on DXpeditions to KH6, Zone 2, PJ4, LZ and J3. Either as SOABHP, MS or M2, his station has finished top in North America for 6 straight years, including several #2 World finishes. W1UE is also the current NA record holder for SOABHP and MS in CQ WW RTTY. DX-wise, he only needs VU/a and P5 to have worked all current countries, but is a bit behind on his submissions. Planned activities for the remainder of 2014 include a major effort in CQ WW RTTY and activating W100AW on RTTY using a multi-channel decoding setup.
3 of 20 Dennis Egan W1UE Operating here in the LZ Field Competition, Dennis is enjoying Bulgaria’s version of Field Day!
4 of 20 Ed Muns W0YK Ed’s primary interest in amateur radio is CW contesting and DXing. In 2004 he entered his first RTTY contest and has enjoyed the RTTY mode. It has helped him improve his operating skills across all modes. He is the contest director for the CQ RTTY contests (WW and WPX), the NCJ NA RTTY Sprint and co-sponsors the 10-Meter RTTY Contest with AA5AU. Ed also authors the RTTY Contesting column in the NCJ. After 32 years with Hewlett-Packard Company as an engineer and executive, he now farms wine grapes on 13 of his 77 acres in the Santa Cruz Mountains. Muns Vineyard designated wine is found on several well known labels as well as on his own brand--Muns Vineyard.
5 of 20 Ed Muns W0YK Operating here as P49X, Ed is also licensed as 7J1ACJ and is the trustee for Loma Prieta Contest Club call signs KY0W & K6YT and NCCC call signs K6CQP, N6CQP and W6CQP.
6 of 20 Digital Modes used in DXing RTTY (45.45 Baud, 170 Hz shift) PSK31 JT65 others
7 of 20 Advice from the Experts Listen, and then listen some more! Short messages Split proficiency “Slow Down to Win” –Listen, then call when it is quiet Practice in contests Police
8 of 20 Listen, Listen, Listen Same as CW and SSB Optimize your decoding Dual-receive highly recommended – requires 2 RTTY decoders Figure out the pattern
9 of 20 RTTY Messages Short: – TU, optionally – your call (no DE) 1-2 times after CQ, then listen 0-1 time only in report – 599 once – nothing else, unless the DX asks for it Modular: – short message elements – chain together
11 of 20 Other Tips RTTY has more “quiet times” in which to drop your call Contest activity for practice Don’t police or talk to policemen – maybe a well-timed ‘UP 2’
12 of 20 Perspective of a DX Station Split up 2, narrow as possible RX band Short messages DXers should listen and determine pattern Problems from DXers: – long calls; long exchanges – calling out of turn – not listening Some DXpedition management may ask: “Why are we doing RTTY?”
13 of 20 Perspective of the DX Station DX has nominally only 3 messages: – CQ P49X P49X CQ – W0YK 599 – TU P49X UP DXers: – should send call only 2-3 times, then listen – report: 599 W0YK
14 of 20 What is RTTY? A pair of out-of-phase CW signals – Mark and Space, 170Hz apart – Baudot code, rather than Morse 60 WPM (45.45 Baud) Requires SW (or, HW) decoder/encoder – UI is text keyboard/display
15 of 20 What is RTTY? … receiving Local “tones” are like CW pitch – default 2295/2125 – your choice; low is less fatiguing – independent of RF transmission
16 of 20 What is RTTY? … transmitting Two (religious) choices: FSK (Frequency Shift Keying) – just like CW AFSK (Audio FSK) – Local tones into SSB mic input – offset dial frequency suppressed carrier +/- local tone Pseudo-FSK – FSK keying circuit driven by AFSK tones
17 of 20 How? RTTY decoder for receive – software, e.g., MMTTY (free) – hardware, e.g, PK232, Hal DXP38 RTTY encoder for transmit – often bundled with decoder and called a MODEM (modulator-demodulator), or TNC (Terminal Node Controller) Standalone or integrated into logging SW Interface between radio and decoder/encoder (PC)
18 of 20 How? … commercial or homebrew interface Receive (decoder) is typically a standard audio cable Transmit (encoder) – FSK: CW-like keying interface – AFSK: standard audio cable – Pseudo-FSK: special converter interface