- Digital modes like JT65, JT9, MSK144, and the new FT8 mode can be used for meteor scatter and DX on VHF and HF bands. - These modes are designed for weak signal communication and can complete contacts using very low power levels, even down to 5 watts. - The new FT8 mode may be a potential game changer for 6m DX because it has a much shorter transmission cycle of 90 seconds compared to JT65's 6 minute cycle, making it better suited for the unstable propagation during sporadic E openings.

1. Digital modes for meteor
scatter & DX
Keith Heimbold, NZ5F
Source materials from NSARC and VE7AFZ, Mark Spencer,
and NCDXC and NA6XX, Chuck Jones and Joe Taylor, K1JT

2. DigitalModes JT65,JT9, MSK144, andNewFT8
• Background / why use digital modes
• What are the JT Modes
• Why might you want to use the JT modes (or not)
• What can you do with them
• How do you use them ?
• wsjt-x for VHF using MSK144, JT65, JT9 and new FT8
• Many concepts presented should be useful for other digital
modes

3. • Background - Why I use Digital Modes
• Fairly mediocre 6m and HF setup (no beam on HF) – moved to
rental home
• Desire to work 80 and up with limited capabilities
• Wanted to be able to work more DX on 6m and hams
everywhere are adopting digital modes for 6m DX
DigitalModes JT65,JT9, MSK144, andNewFT8

4. • JT9 made 80M and 160M viable for my pipsqueak home station
• Operation is mostly on pre determined frequencies
• I prefer the JT modes to PSK31 / RTTY
• A good choice in my view for very weak signals and or low power
levels on HF and at higher power on 6m
• I like the technology, software, and wsjt-x 1.7 is a great digital mode
application
DigitalModes JT65,JT9, MSK144, andNewFT8

5. • What are the “JT” Modes ?
• A set of “sound card” digital modes created by a team lead by
Joe Taylor K1JT (creator of wsjt-x)
• Originally intended for EME / VHF and up weak signal work
(ie. Earth Moon Earth)
DigitalModes JT65,JT9, MSK144, andNewFT8

6. • Designed to complete a QSO. Not well suited to rag chewing.
• Exchange call signs, signal reports and maybe location / grid
square
• JT65 is a six minute QSO sequence. This can cause issues for
sporadic E (QSO completion can be challenging for 6m DX)
• New FT8 mode created by Joe Taylor and friends completes a
contact in 90 seconds (Woohoo!!!)
• JT9 allows for 13 character random messages
DigitalModes JT65,JT9, MSK144, andNewFT8

7. • You control your radio and communicate with other stations
via your computer
• Your computer generates the signals your radio transmits
• Your computer decodes and displays the received signals
• Structured TX RX times (Time on your PC is important) – NTP
sychronization required. You need to have computer
connected to internet to keep time synced.
DigitalModes JT65,JT9, MSK144, andNewFT8

8. DigitalModes JT65,JT9, MSK144, andNewFT8

9. • JT65 and JT9 feature robust error detection and correction,
designed for weak but fairly constant signals
• MSK441 wide band, no error correction Designed for
infrequent signals (Meteor Scatter and other similar
applications)
• FT8 has shorter cycle 90 seconds and is made for multi hop Es
and DX
DigitalModes JT65,JT9, MSK144, andNewFT8

10. • My experience (your mileage may vary (: )
• Can make world wide qso’s on the higher HF bands with
modest power levels (5 to 30 watts)
• Often at 5 watts
• Much easier than on RTTY, many qso’s at less than 5 watts vs
100 watts in the past on RTTY
• Can make North American wide QSO's on lower HF bands,
typically at less than 5 watts
• On VHF, recommend using higher power. 100W was not
enough for me to make contact with JA even though band was
open and I was using a nine element M2.
DigitalModes JT65,JT9, MSK144, andNewFT8

11. • MSK 441 Meteor Scatter
• Bounce signals from meteor trails and off airplanes
• In the absence of meteor showers, works best in the
mornings, but possible more or less any time with patience
and power
• Less dependent on antenna height and a clear view of the
horizon than terrestrial VHF weak signal propagation is. An
advantage in the winter when access to mountain tops is
difficult
• Useful for portable work
DigitalModes JT65,JT9, MSK144, andNewFT8

12. • MSK 441 Meteor Scatter
• Can make QSO’s between 300 thru 1,300 miles on VHF (typical min
and max range)
• Internet commonly, Skype, (but not always) used to co ordinate
QSO’s via Meteor Scatter
• Reasonably certain for me on 50 MHz in the mornings (average of 20
min per opening at my previous QTH)
• 144 and 222 MHz involve more effort generally and require
additional power generally for it to work beyond line of sight
DigitalModes JT65,JT9, MSK144, andNewFT8

13. • So what is needed to use the JT Modes ?
• SSB Transceiver Helpful features (not essential)
• High stability option / TCXO
• Data connections or built in sound card
• Switchable AGC
• Monitor function
• Narrow filters not needed (usually run at 2.4 khz or wider
bandwidth)
• Computer does the audio processing
• Download WSJT-X (1.7) at
http://www.physics.princeton.edu/pulsar/K1JT/wsjtx-
doc/wsjtx-main-1.7.0-devel.html
DigitalModes JT65,JT9, MSK144, andNewFT8

14. • What is needed to run the JT Modes ?
• Computer Windows / Mac / Linux
• 1.5 GHz CPU (windows) Faster is helpful
• Sound card that supports 48 KHz sampling (unless radio or
interface has its own soundcard.)
• 16 bit sound card is fine
• Means of keeping computer clock set to an accuracy of one
second (Critical!!!)
DigitalModes JT65,JT9, MSK144, andNewFT8

15. DigitalModes JT65,JT9, MSK144, andNewFT8

16. DigitalModes JT65,JT9, MSK144, andNewFT8

17. DigitalModes JT65,JT9, MSK144, andNewFT8

18. DigitalModes JT65,JT9, MSK144, andNewFT8

19. • Easy to install and use NetTime synchronization tool
• It is free and works great (donations optional)
• www.timesynctool.com
DigitalModes JT65,JT9, MSK144, andNewFT8

20. • What is needed to run the JT Modes ?
• Radio computer interface
• Lots of choices
• Build or Buy ?
• Some radios have a USB port
• Some interface units have their own sound cards,
other use the sound card in your PC
• 48 KHz sampling rate is important
DigitalModes JT65,JT9, MSK144, andNewFT8

21. DigitalModes JT65,JT9, MSK144, andNewFT8

22. DigitalModes JT65,JT9, MSK144, andNewFT8
Ensure you load any required software to enable connection to
your rig before connecting your rig to the computer (Yaesu,
Kenwood, and Icom all have OEM software that needs to load first)

23. DigitalModes JT65,JT9, MSK144, andNewFT8

24. • General Tips
• Always use USB Mode (unless you have Digital mode (ensure it
is Digital – USB)
• Watch power TX power, and ALC
• No or minimal ALC indication, moderate power on HF; more
on 6m
• Compression should be off
• If another station gives you a weak report (-23 or less ?)
consider increasing power if possible on HF
• If you receive very strong reports (-10 or more ?) consider
reducing power on HF
• Run maximum power on 6m during Es season and for DX
DigitalModes JT65,JT9, MSK144, andNewFT8

25. • Receiving hints
• When receiving weak signals in the presence of strong signals
turning off AGC may help or putting AGC on Fast
• Use wide SSB filter settings
• Very strong signals may not decode with some modes (I.e..
FSK and MSK 441)
• Use the decoding options (I.e. deep.)
DigitalModes JT65,JT9, MSK144, andNewFT8

26. • Major propagation modes
• Es – the workhorse of 6M DX’ing ( includes AU E’s on northern
paths)
• F2 – rare as solar cycle has declined (no E-W F2 in SC24)
• TEP – almost always Es / MS linked (SA and CA)
• SSSP – likely multiple Es (JA and Asia from NA)
• TEFE – transequatorial to Far East (FK8, ZL, VK – rare now)
DigitalModes JT65,JT9, MSK144, andNewFT8

27. • Daily diurnal peaks
• 1500 – 1800 UTC
• 2100 – 0100 UTC
• 0500 – 1100 UTC
• 27 day solar rotation related
• Watch for peak SFI / 304A peaks – repeats
• Watch leading edge of solar & geomag events
• Annual / season related
• May – August = E’s season to Carib, SA, EU, AF, Asia, S. Pac.
• October - December = TEFE to VK/ZL & F to KG6
• January – May = E’s linked TEP to SA
• Solar cycle related
• Best E’s seasons seem to be a mean of 5 years out of phase with solar
max ( 4-7)
• Active solar conditions suppress E’s / enhance F2
DigitalModes JT65,JT9, MSK144, andNewFT8

28. • Antennas
• 1-2 x Es nearly anything radiating works
• 5-8 elements seem to be sweetspot
• Vertical stack ( 2 x 5-8 el) significantly improves fading / QSB
• Lowest antenna need only be 20 – 40 ft.
• Low loss feed-line
• Hard line to rotor base. LMR400 to feed-point
• Rigs
• Most modern transceivers adequate sensitivity, selectivity
• External noise is biggest problem.
• Look for excellent NB/NR features
• Look for good CW filters
• Spectral display is a big advantage ( beacons )
• Power
• 200W - 500W gets good results
DigitalModes JT65,JT9, MSK144, andNewFT8

29. 2016 &2017 6mDX with JT65
One received
transmission
of EI4DQ - No
QSO
Completed
QSO with
EA6SX
• JT65 is a cool program but propagation must be stable for it to be viable for
completed QSOs on 6m.
• In 2016, I saw a few Europeans on 6m JT65 (~10 different stations and only
completed two QSOs, mostly due to propagation).
• Until a better mode with shorter transmission cycle is developed, I still think CW is a
better mode for 6m DX, however, adoption of JT65 for 6m DX is surging.

30. 2016 &2017 6mDX with JT65
Plethora of JAs
Received by JA
Not confirmed
• This year openings seem to be very good to the west and we have had many JA
openings into EL09
• Not much time on radio this year but this is what many of us experienced this past
Sunday

31. NewMode –FT8 (potentialgamechanger)
• Much shorter QSO
cycle only 90
seconds
• Only slightly less
senstivity
• Narrower
bandwidth taken
• Potential game
changer
• Designed with 6m
in mind but works
on HF too

32. Questions???