How Do I Set It Up? - Contest University

How Do I Set It Up? - Contest University
CTU 2013 Presents
Setting Up for RTTY Contesting—
Basic to Advanced
Ed Muns, W0YK
The Cynics Say …
“The RTTY decoder/encoder does everything.”
however, this attribute …
frees the operator to improve other skills
enables more contest participants
provides mode diversity for contest junkies
“RTTY is a pain to set up and get working.”
… stay tuned, it’s really not that difficult!
2/76
RTTY Contesting Setup
What is RTTY?
How do I set it up?
Radios
Loggers: N1MM, WriteLog, Win-Test
Part 2: “Operating a RTTY Contest”
3/76
RTTY Contesters
2010 survey
• 825 participants; 13 questions
• conducted in February 2010
4/76
What is RTTY?
compared to CW
CW
One RF carrier
RTTY
Two RF carriers 170 Hz
apart (Space & Mark; Shift)
Local audio tones
One on and other off
Local audio pitch
On or off
key up is data 0
key down is data 1
Space is data 0
Mark is data 1
Morse code
Baudot code
typically 25-40 wpm
constant 60 wpm
(or 45.45 Baud)
5/76
What is RTTY?
Space & Mark
http://rfwireless.rell.com/pdfs/TN_WJfsk.pdf
6/76
What is RTTY?
45.45 Baud = 60 WPM
Asynchronous character stream
1 bit Start pulse (Space)
5 bits of data (character code)
1, 1.5 or 2 bits Stop pulse (Mark)
7/76
What is RTTY?
code history
Baudot code (1870)
Manual bit entry
5-bit ITA1 code
Two 32-bit character sets
letters
figures
Murray code (1901)
Teletype character entry
Western Union variation
5-bit ITA2 code (1930)
USTTY variation
ASCII (1967)
7-bit ITA5 code
8/76
Code
11111
11011
00000
00100
01000
00010
00011
11001
01110
01001
00001
01101
11010
10100
00110
01011
01111
10010
11100
01100
11000
10110
10111
01010
00101
10000
00111
11110
10011
11101
10101
10001
Control Characters
LTRS
FIGS
Null
Space
LF
CR
Figures
Letters
ITA2 USTTY
A
B
?
C
:
D
ENQ
$
E
3
F
!
G
&
H
#
I
8
J
BELL
'
K
(
L
)
M
.
N
,
O
9
P
0
Q
1
R
4
S
'
BELL
T
5
U
7
V
;
W
2
X
/
Y
6
Z
"
What is RTTY?
Figures Shift
The LTRS and FIGS characters do not print
The code for the characters “Q” and “1” is the same; which
one prints depends on if you are in Letters or Figures set
Note that the LTRS, FIGS and space characters appear in
both sets
Example: “KI7GUO DE K4GMH” gets sent as:
LTRS K I FIGS 7 LTRS G U O Space D E Space K FIGS 4
LTRS G M H
Why do we care to understand this?
If a burst of static garbles the LTRS or FIGS character,
then what prints after that is from the wrong set until the
next LTRS or FIGS character appears
9/76
What is RTTY?
UnShift on Space
UnShift On Space (USOS or UOS)
Increases noise immunity for alpha text
Space character forces a shift to the Letters set
Contest exchanges are alpha and numeric
Should UOS be on or off?
Should Space or Hyphen delimit exchange elements?
599 JOHN NY or 599-JOHN-NY
Recommendation:
Turn on both RX & TX UOS and use Space delimiters
Explained in “Operating an RTTY Contest”
10/76
What is RTTY?
audio tones
Space and Mark audio tones
Default: 2295 and 2125 Hz
Less fatiguing: 1085 and 915 Hz
Analogous to CW pitch
Operator choice
Each operator can use different tone pairs
Transmission is always two carriers 170Hz apart
Must be same in radio and decoder/encoder
11/76
AFSK vs. FSK
2010 survey
• AFSK has been overtaken by FSK
since it first appeared in radios, circa 1990
12/76
What is RTTY?
AFSK vs. FSK
Two methods of transmission:
AFSK (Audio Frequency Shift Keying)
keyed audio tones into SSB transmitter via:
Mic input, or
Auxiliary audio input. e.g., Line In
FSK (Frequency Shift Keying)
keys the transmitter just like CW
Note: Receiving is the same in either case.
13/76
What is RTTY?
dial frequency
spots are often wrong
RTTY RF is independent of local audio tones and
whether LSB or USB is used:
The higher RF frequency is the Mark (14090.000 kHz)
The lower RF frequency is the Space (14089.830 kHz)
The difference between the two is the shift (170 Hz)
FSK displays Mark (14090.000 kHz)
AFSK displays suppressed carrier which varies with local
audio tones and sideband used!
For Mark tone of 2125 Hz (Space tone of 2295 Hz):
LSB (14092.125 kHz)
USB – Mark & Space tones reversed (14087.005 kHz)
14/76
What is RTTY?
AFSK vs. FSK
AFSK
FSK
Indirect (tones Mic input)
Any SSB radio (esp. legacy)
SSB (wide) filtering
Dial = sup. car. frequency
VOX
Audio cable (same as PSK31)
Must use high tones
NET (automatic TX tone control)
Less bandwidth (sometimes)
Direct (like CW keying)
“Modern” radios
RTTY (narrow) filtering
Dial = Mark frequency
PTT
COM FSK keying cable
Can use low tones
No audio level adjust
No disabling speech proc.
No erroneous sound keying
Less pitfalls
Easier hook-up; NET
15/76
What is RTTY?
summary
Uses 5-bit Baudot … er … USTTY code with two sets
of 32 characters: Letters and Figures
Space & Mark frequencies separated by 170 Hz “Shift”
Local Space & Mark tones analogous to pitch in CW
Constant 45.45 Baud (60 wpm) asynchronous
character stream with 5 data bits and 2-3 sync bits
Figures Shift & Letters Shift
optional UnShift-On-Space (UOS)
AFSK vs. FSK transmission (receiving is the same)
Radio dial frequency differences
100% duty cycle!
16/76
How Do I Set it Up?
overview
Acquire hardware and/or software to convert
between the RTTY signal and text:
RTTY receive decoder
RTTY transmit encoder
Configure decoder/encoder
Integrate decoder/encoder with logger
The rest of the station setup is the same as for
CW and SSB
17/76
How Do I Set it Up?
RTTY decoder/encoder
RTTY receive decoder
converts printed characters
from the two RTTY
frequencies
RTTY transmit encoder
converts typed characters
(or messages) into the two
RTTY frequencies
CW and SSB receive audio
is converted to typed
characters by our
ears/brain/hands
Transmitted CW is
converted from text by our
brain/hand with the aid of a
key and/or keyer
Transmitted SSB is
converted from text by our
brain/mouth via a
microphone
(CW decoders are also
available, similar to RTTY
decoders, but seldom used)
(CW software keyers and
SSB DVKs are also used,
similar to RTTY encoders)
18/76
How Do I Set it Up?
decoder/encoder terminology
The RTTY transmit encoder and receive
decoder is sometimes referred to as a
MODEM or a TNC:
MODEM = MOdulator DEModulator
TNC = Terminal Node Controller
MODEMs can be:
a hardware box, or
a software application driving a PC soundcard
19/76
How Do I Set It Up?
hardware MODEM
AFSK
Radio
RX
TX
audio input
audio out
Line Out
Line In
MODEM
Computer
Term. Em. or Graphic UI
20/76
How Do I Set It Up?
hardware MODEM
AFSK
FSK
Radio
Radio
RX
RX
TX
audio input
audio out
audio out
Line Out
Line In
TX
FSK input
Line In
FSK output
MODEM
MODEM
Computer
Computer
Term. Em. or Graphic UI
Term. Em. or Graphic UI
21/76
How Do I Set It Up?
hardware MODEM
22/76
How Do I Set It Up?
software application & soundcard
AFSK
FSK
Radio
Radio
RX
audio out
TX
RX
audio input
audio out
TX
FSK input
PTT
FSK & PTT
keying cable
Line In
Line In
Line Out
Soundcard
Soundcard
Serial port
Computer
Computer
RTTY decoder/encoder
RTTY decoder/encoder
23/76
How Do I Set It Up?
ground loops
Eliminate ground loops between radio and PC
Otherwise insert 1:1 audio isolation transformer on:
RX output
TX Mic input (AFSK only)
Alternatives:
Bourns LM-NP-1001-B1L transformer
homebrew cable
Ground loop isolators
W2IHY iBox
Commercial RTTY interfaces
K3 (uses Bourns LM-NP-1001-B1L on LINE IN & OUT)
24/76
How Do I Set It Up?
homebrew audio isolation
Bourns LM-NP-1001-B1L
$1.78
-90 dBc 3rd order IMD
25/76
How Do I Set It Up?
ground loop isolators
Radio Shack $19.49 or eBay $6.99
eBay $3.35
-64 dBc 3rd order IMD
eBay $5.50
eBay $7.45
26/76
How Do I Set It Up?
W2IHY iBox audio isolation
$60
27/76
How Do I Set It Up?
commercial interface audio isolation
Rascal
28/76
How Do I Set It Up?
radio audio isolation
K3 audio isolation
29/76
IN – LINE – OUT
How Do I Set It Up?
radio IF filtering
PC Audio isolation
Transformer
Commercial interface
Some radios (K3)
Narrow IF filters (Roofing & DSP)
400 Hz - normal
250-300 Hz - strong QRM
Tone filters??
Icom Twin Peak Filter
K3 Dual-Tone Filter
Audio filtering
JPS NIR-10/12
Timewave DSP-599zx
Modern DSP rigs
30/76
How Do I Set It Up
AF filtering
PC Audio isolation
Transformer
Commercial interface
Some radios (K3)
Narrow IF filters (Roofing & DSP)
400 Hz - normal
250-300 Hz - strong QRM
Tone filters??
Icom Twin Peak Filter
K3 Dual-Tone Filter
Audio filtering
JPS NIR-10/12
Timewave DSP-599zx
Modern DSP rigs
31/76
How Do I Set It Up?
soundcard levels
Adjust levels in Windows Volume Control
(or, in MMTTY Options/Soundcard …)
Use isolation transformer
Avoid over-drive
Mute other inputs and outputs
RX audio goes to LINE IN (or, MIC w/pad)
Options/Soundcard input level
TX AFSK audio (mic) comes from LINE OUT
Options/Soundcard output level
Turn off radio compression (speech proc.)
32/76
How Do I Set It Up?
PTT vs. VOX
AFSK uses VOX (or PTT); FSK uses PTT
PTT by:
Computer control via Serial COM port
Footswitch (not recommended)
FSK to use semi-break-in in the future?
33/76
How Do I Set It Up?
homebrew FSK & PTT keying cable
FSK: TXD (3)
PTT: RTS (7)
(DB9 pin #)
34/76
FSK input
PTT input
Gnd (5)
on radio
How Do I Set It Up?
W3YY FSK & PTT keying cable
35/76
How Do I Set It Up?
RASCAL
commercial interfaces
36/76
How Do I Set It Up?
commercial interfaces
See May-June 2012 NCJ, “RTTY Contesting” column
37/76
How Do I Set It Up?
RigExpert Interfaces
38/76
How Do I Set It Up?
microHAM interfaces
One Radio
SO2R
39/76
How Do I Set It Up?
RigExpert & microHAM interfaces
See May-June 2012 NCJ, “RTTY Contesting” column
40/76
How Do I Set It Up?
summary - receive
1. Use appropriate receiver IF and AF filtering.
2. Receiver Audio Out (via isolation) to …
MODEM Audio In:
Set level so band noise is just above threshold
OR
MMTTY via Soundcard Line In (or Mic In with pad):
Enable soundcard Line In (or Mic) input, disable/mute other
inputs
Increase level so band noise is just above threshold
41/76
How Do I Set It Up?
summary - AFSK
1. Turn off speech processor in radio; enable VOX
2. Connect radio’s Line In (Mic In with pad) via
isolation to:
MODEM Audio Out
Set radio Mic level to just reach peak power output
OR
Soundcard Line Out
Enable soundcard WAV output, disable/mute other outputs
Increase WAV level and/or radio Mic level to just reach
peak power output
42/76
How Do I Set It Up?
summary - FSK
1. Connect the radio FSK and PTT inputs to:
the MODEM FSK and PTT outputs and connect the
MODEM Serial port to the PC
OR, if MMTTY
the RTTY interface FSK and PTT outputs and
connect the interface Serial or USB port to the PC
2. If no PC Serial port, then use a USB-Serial
adapter.
Beware that some won’t key FSK properly. Edgeport
USB-Serial adapters are known good.
43/76
Decoders
2010 survey
• 87% use soundcard decoding/encoding
• 86% of soundcard users run MMTTY
•2Tone introduced late 2012
44/76
Decoders
MMTTY
Dominant soundcard MODEM in use today
Exceeds performance of most other MODEMs
Freeware since introduction in 2000
Mako, JE3HHT
45/76
Decoders
2Tone
Outperforms MMTTY
Uses less CPU cycles
AFSK only
Pseudo FSK
Contest loggers:
N1MM Logger
WriteLog
Introduced late 2012
David Wicks, G3YYD
46/76
Decoders
Logger Support
Feature
MMTTY
AFSK
FSK
WriteLog
☻
☻
N1MM Logger
☻
☻
Win-Test
☻
☻
2Tone
AFSK
FSK
☻
☻
NET on
not available
47/76
Decoders
Logger Support
Feature
MMTTY
AFSK
FSK
WriteLog
☻
☻
N1MM Logger
☻
☻
Win-Test
☻
☻
2Tone
AFSK
FSK
☺
☺
☺ The “Sweet Spots”
48/76
How Do I Set It Up?
Squelch
MMTTY standalone
Messages
Leave UOS on
Don’t click
in display
Turn off: NET
AFC
received
text
transmitted
text
49/76
How Do I Set It Up?
MMTTY Option menu
Soundcard
levels
MMTTY
setup
50/76
How Do I Set It Up?
MMTTY Option/Setup/Demodulator
Set tones
51/76
How Do I Set It Up?
MMTTY Option/Setup/TX
TX UOS on
FSK/PTT port
Select LTR
Soundcard
Line Out level
512 Tap
52/76
How Do I Set It Up?
MMTTY Option/Setup/Misc
AFSK
Soundcard
FSK
53/76
How Do I Set It Up?
MMTTY Option/Setup/SoundCard
Select receive
Soundcard
Select transmit
Soundcard
(AFSK only)
54/76
How Do I Set It Up?
MMTTY userpara.ini
userpara.ini file (in MMTTY program directory)
stores parameter defaults
There is a section for each profile, e.g.,
[Define0]
Name=Standard RTTY
In each section (profile) make sure:
NET and AFC are off [NET=0, AFC=0]
UOS and TXUOS are on [UOS=1, TXUOS=1]
Other parameters are set so that they do not have to be
changed every time you load MMTTY or that profile
55/76
How Do I Set It Up?
2Tone
56/76
How Do I Set It Up?
2Tone
Setup vs. Settings
same
Window-width adjust
57/76
RTTY Radios
2010 survey
• Icom 756Pro series most popular
• Elecraft K3 growing rapidly
58/76
RTTY Radios
AFSK bandwidth
MMTTY - AFSK
No TX filter
K3 @ 1 mW
Thanks K0SM (http://www.frontiernet.net/~aflowers/k3rtty/k3rtty.html)
MMTTY - AFSK
Default 48-tap TX BPF
K3 @ 1 mW
59/76
RTTY Radios
AFSK bandwidth
MMTTY - AFSK
Default 48-tap TX BPF
K3 @ 1 mW
Thanks K0SM (http://www.frontiernet.net/~aflowers/k3rtty/k3rtty.html)
MMTTY - AFSK
512-tap TX BPF
K3 @ 1 mW
60/76
RTTY Radios
AFSK bandwidth
MMTTY - AFSK
512-tap TX BPF
K3 @ 1 mW
Thanks K0SM (http://www.frontiernet.net/~aflowers/k3rtty/k3rtty.html)
2Tone - AFSK
Default “AM” setting
K3 @ 1 mW
61/76
RTTY Radios
PA IMD impact on AFSK bandwidth
MMTTY - AFSK
512-tap TX BPF
K3 @ 1 mW
Thanks K0SM (http://www.frontiernet.net/~aflowers/k3rtty/k3rtty.html)
MMTTY - AFSK
512-tap TX BPF
K3 @ 100 watts
62/76
RTTY Radios
PA IMD impact on AFSK bandwidth
MMTTY - AFSK
No MMTTY filter
K3 @ 100 watts
Thanks K0SM (http://www.frontiernet.net/~aflowers/k3rtty/k3rtty.html)
MMTTY - AFSK
No MMTTY filter
K3 AFSK filter
K3 @ 100 watts
63/76
RTTY Radios
PA IMD impact on AFSK bandwidth
MMTTY - AFSK
512-tap TX BPF
K3 @ 100 watts
Thanks K0SM (http://www.frontiernet.net/~aflowers/k3rtty/k3rtty.html)
MMTTY - AFSK
No MMTTY filter
K3 AFSK filter
K3 @ 100 watts
64/76
RTTY Radios
PA IMD impact on RTTY bandwidth
FSK/MMTTY/2Tone
FSK unfiltered
MMTTY 512-tap BPF
2Tone “AM” setting
K3 @ 1 mW
FSK/MMTTY/2Tone
Same encoders
K3 @ 100 watts
Thanks K0SM (http://www.frontiernet.net/~aflowers/k3rtty/k3rtty.html)
Thanks W7AY for composite graphics
65/76
RTTY Radios
FSK bandwidth
Old K3 FSK bandwidth
No waveshaping
< DSP281 firmware
Typical of all radios
50 watts
Thanks K0SM (http://www.frontiernet.net/~aflowers/k3beta/)
New K3 FSK bandwidth
Optimal DSP filter
DSP281+ firmware
Lobby other mfrs to add
a FSK filter!
66/76
RTTY Radios
FSK & AFSK bandwidth
AFSK
Use radio AFSK filter
FSK
Use radio FSK filter
DSP TX filter (K3)
Crystal TX filter (K3)
Lobby other mfrs
DSP TX filter (K3)
Crystal TX filter (K3)
Lobby other mfrs
Use MODEM TX filter
Use AFSK
2Tone default
MMTTY 512-tap
With TX filtering
Properly adjusted
67/76
RTTY Contest Loggers
2010 survey
• MixW ahead of Win-Test
• MMTTY used stand-alone
68/76
69/76
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2012 CQ WPX RTTY
3550 submitted logs
2000
1800
1600
1400
1200
1000
800
600
400
200
0
RTTY Contest Loggers
WriteLog (1994)
created for RTTY (CW & SSB came later)
www.rttycontesting.com web site
N1MM Logger (2000; dedicated RTTY software designer)
Free
Win-Test (2003; RTTY is low priority)
All three integrate MMTTY and have similar functionality
for basic RTTY contesting.
70/76
RTTY Contest Loggers
WriteLog
MMTTY
☻
2Tone
☻
other decoders
☻
Call sign acquisition
☻
Contests supported
☻
Advanced RTTY
☻
N1MM
☻
☻
some
☻
☻
☻
Win-Test
☻
none
☻
fewer
none
• All three are entirely adequate for basic RTTY contesting
• Use the logger you are already familiar with for CW & SSB
71/76
RTTY Contest Loggers
relative ratings
13 features compared
Rated 0 to 5
Simplifying assumption: features equally weighted
All three score ‘5’ on:
MMTTY integration
Stateful Enter key (ESM: Enter Sends Message)
Accelerator keys
QRV message parameter
Another 9 advanced RTTY features distinguish
these loggers
72/76
RTTY Contest Loggers
relative ratings
WL N1 WT Logger
5
3
4
RTTY window readability
5
4
0
Multiple decoders
5
4
0
multiple MMTTY or 2Tone
0
5
3
ESM mouse ctrl & Sprint mode
5
5
0
SO2V
5
3
3
M2 SO2R configuration
5
4
5
Re-mapped keys
5
5
3
Call sign stacking
5
3
5
AFSK/FSK flexibility
40 36 23 Overall
73/76
A Blizzard of Details!
this is fun??
Start Simple, Then Enhance
MMTTY (free)
get RX working (std audio cable from radio to PC)
get TX working; use either:
AFSK (2nd std audio cable from radio to PC)
FSK (keying cable or commercial interface)
Integrate MMTTY or 2Tone with logging software
Enhance later
Audio isolation (highly recommended)
Commercial interface
Advanced setup: SO2V, SO2R, multiple decoders, ...
74/76
Resources
www.rttycontesting.com
Tutorials and resources (beginner to expert)
WriteLog/MMTTY/2Tone (N1MM Logger coming)
rtty@contesting.com
Email reflector
RTTY contester networking
Q&A
Software web sites
mmhamsoft.amateur-radio.ca/ (MMTTY)
n1mm.hamdocs.com/tiki-index.php (N1MM Logger)
www.writelog.com (WriteLog)
www.wintest.com (Win-Test)
Software Reflectors
mmtty@yahoogroups.com (MMTTY)
N1MMLogger@yahoogroups.com (N1MM Logger general)
N1MMLogger-Digital@yahoogroups.com (N1MM Logger RTTY & PSK)
writelog@contesting.com (WriteLog)
support@win-test.com (Win-Test)
75/76
Operating a RTTY Contest
RTTY considerations
Optimize message buffers
UnShift On Space (UOS or USOS)
Space vs. Hyphen
Accelerator keys; Stateful Enter key (ESM); key re-mapping
Super Check Partial & Pre-Fill
“Slow down to win” (call sign stacking)
Multiple decoders
SO2V, SO2R-SOnR
Logging Software: WriteLog vs. N1MM Logger vs. Win-Test
Ergonomics
76/76
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