Introduction to Digital DXing
Dennis Egan W1UE
Ed Muns W0YK
17 July 2014
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.
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Dennis Egan W1UE
Operating here in the LZ Field Competition, Dennis is enjoying Bulgaria’s version of Field Day!
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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.
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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.
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Digital Modes used in DXing
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RTTY (45.45 Baud, 170 Hz shift)
PSK31
JT65
others
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Advice from the Experts
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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
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Listen, Listen, Listen
• Same as CW and SSB
• Optimize your decoding
• Dual-receive highly recommended
– requires 2 RTTY decoders
• Figure out the pattern
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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
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Split Operation
• Build skill
• Always double-check settings
• Requires:
– sub-receiver + 2 RTTY decoders
– or, agile operation of A/B VFOs
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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’
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Perspective of a DX Station
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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?”
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Perspective of the DX Station
• DX has nominally only 3 messages:
– CQ P49X P49X CQ
– W0YK 599 <W0YK>
– TU P49X UP
• DXers:
– should send call only 2-3 times, then listen
– report: <TU> 599 W0YK
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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
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What is RTTY? … receiving
• Local “tones” are like CW pitch
– default 2295/2125
– your choice; low is less fatiguing
– independent of RF transmission
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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
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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)
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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
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Resources
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www.rttycontesting.com
rtty@contesting.com
Dayton CTU RTTY presentations
NCJ RTTY Contesting column
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Happy RTTY DXing!
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