RTTY Digital Mode Contesting and Prep for Field

RTTY Digital Mode Contesting and Prep for Field Day Use N 6 MDV K 6 VHY January 16, 2018

Why This Briefing? • It has been suggested we do more digital modes in 2018 – Field Day 2018 Digital Modes RTTY is an option • Why? – Enables contacts on higher bands despite poor sunspot propagation • Lower SNR required than phone contacts – Develop additional skills for weak signal emergency communication – Easier to learn than CW for weak signal use – Possibly attract additional operators who don’t do CW or Phone

Contents • Understand RTTY mode • What you will need to do RTTY on Field Day • What you need to set up your own RTTY capability • Not included… – Should we use RTTY, PSK 31, FT 8, MFSK or other digital mode – Answer is YES, we should be prepared to use those modes

What is a Digital Data Mode • Means of sending text messages between computers via Ham radio communication • Using a windows or unix based computer: – Open a digital data mode program – Set some station information • Your name, call sign, maidenhead square code, and ITU zone • These are used by the program to send common information – Only your call sign is essential • Set up connection to the radio – Data connection • Can be an analog audio in and out to a sound card • Some radios have special RTTY digital data connection • Some means to activate the transmitter push to talk – May need to set up com ports/usb ports on the computer

RTTY Digital Data Mode • RTTY Radio Tele. TYpe – – Known for contesting and faster Two tones: 2295/2125 Hz Transmission speed: 45 baud, 5 bit characters => 60 WPM Bandwidth: 250 Hz Typically at xx. 080 – xx. 099 part of the band • Used to send text from one computer to another – via Ham radio transceiver • Messages of any length – originally based on mechanical teletype • No specific message format – just text transmit/receive • No built in error checking – With low SNR and QRM expect some character errors • Thus common to send critical information twice – like call sign • References: – – https: //www. rttycontesting. com/ aa 5 au. com/Getting. Started. On. Rtty. pdf Photo courtesy of http: //hfradio. org. uk/html/digital_modes. html See that page for sounds also.

Example Digi. Pan for PSK 31 Showing 1 strong signal on the waterfall • Macro buttons across the top • Multiple signal decode on right • Waterfall below

Example of MMTTY Screen Shot for RTTY • Macro buttons can usually be clicked with the mouse • Or • Press a F 1 -9 function key

FLDIGI Another Popular SW Tool One software tool - decodes many modes: PSK, RTTY, MFSK, … Many modes supported, but only one message decoded at a time

For Field Day Operation • A tent that with a RTTY/Digital station set up will have one or two computers – Logging computer – Digital modes computer (if not on the same machine as logging) • It will have an instruction sheet for how to do digital on that equipment – What software program to open (digipan, fldigi, other) – Setting the transmitter power • 100 W for voice SSB • Likely 20 -30 W for digital modes – Possibly how to set the specific windows computer sound level – Adjusting RF gain for good waterfall display • i. e. , lower gain until waterfall shows just signals of interest – What mode to set the radio – typically SSB Upper Side Band USB • Some radios may have a special digital mode – What frequency to tune the transceiver to • Each digital mode has its own commonly used frequencies • RTTY 7. 084, 14. 084, 21. 084 • Set the transceiver and computer as indicated

For Field Day Operation – Search and Pounce • Look to see who is calling CQ for field day and respond if not in log – Click on that person’s frequency on the waterfall • That tunes the software to their frequency and loads their call sign into the macro – Press the macro button for: • <call> de w 6 ha k – When they respond, press the macro to send our info: • <call> tu 3 A LAX de w 6 ha – If there transmission was incomplete press the macro: • <call> agn? Agn? de w 6 ha k • Next move the transceiver frequency – Up or down across the indicated frequency range – E. g. , for RTTY expect signals from • 14. 080 to 14. 150 but avoid 14. 099 -14. 101 – The transceiver bandwidth is likely 2. 4 Khz – So move the frequency up or down 2 KHz to see if there are more stations using this mode Meaning of messages: DE = “this is” K = “over, go ahead” AGN = again abbreviation fd = field day tu = thank you QSL = message received <call> macro fill-in for their call sign

For Field Day Operation – Calling CQ - running • When have finished with others find an open frequency to call CQ – Look on the waterfall and click on an open frequency to call CQ • Tune the transceiver frequency up or down if needed • Try to stay close to where other digital operators are – so you will be found – Note that having your desired frequency in the middle of the displayed waterfall will likely provide a stronger cleaner signal • The radio’s internal filters often attenuate signals near the edge • Four macros when running during a contest – – cq fd de w 6 ha k <call> 3 A LAX de w 6 ha k <call> tu <call> agn? Agn? de w 6 ha k • Press the macro for CQ • If someone responds press the macro for sending info – If not, press the CQ macro again • When they send their information back, press the TU macro and go back to calling CQ • If there information was not clear, press the Agn macro

Hints – Experience from other contests • Propagation is not a constant – You may see the other guy’s signal clearly, but he may not see yours • He may be running higher power or have better antenna • He may have more local QRM which is blocking your signal – Try a few times to respond, if it doesn’t work, move onto someone else • The other guy may respond to you but be off set in frequency – Could be his transceiver/computer are set up poorly – Go ahead and try to respond on your original frequency • After a successful CQ and information exchange… – Some people Jump in on your frequency to try to capture the other guy – I think that is poor form and do not suggest doing that yourself – I’d be inclined to go ahead and just do your CQ again • The jump in’s signal may be clobbered, but … you were on this frequency first – (Note, I see a lot of that on VHF/UHF FM contacts too)

Log the Contact • Depending upon how the radio/computer are set up – The contact may be automatically logged when complete • Or – You will need to type the call sign and information into the logging computer manually – Given how much time it takes to complete the transmission this is easily doable 13

Getting the Field Day Stations Set-up Each band station captain & transceiver owner need to set up for digital • Computer connected to radio via Terminal Node Controller (TNC) – Computer connection to sound card / keyboards / monitor / mouse – Load appropriate software on computer to decode sound & display waterfall • Set up Four macros for running – – cq fd de w 6 ha k <call> 3 A LAX de w 6 ha k <call> tu <call> agn? Agn? de w 6 ha k • Set up Three macros when search and pounce – <call> de w 6 ha k – <call> tu 3 A LAX de w 6 ha – <call> agn? Agn? de w 6 ha k • Test equipment settings – Good signal out • Expected power level • Low distortion • Create instruction sheet

Equipment Setup • Make or buy connection hardware between computer and radio – Audio interface – Remote radio control – Push to talk • Configure computer – Sound levels in and out – Turn off extraneous Windows beeps and sounds – Set appropriate software settings for each mode to be used (call signs, etc. ) • Determine optimum radio settings – Max power for continuous operation (20% of max? ) – Power level and sound card settings for • Expected output power • Low distortion • Appropriate ALC (small to none) • Ideally… – Test operation interference with 100 W SSB on near by transceiver on same band

Example Digital Mode Hook Up • ICOM 7000 Radio RIGblaster TNC • Strong PSK 31 signal • Decoding via Digipan software • Macro buttons across the top • Multiple signal decode on right • Waterfall below – Computer sound card & USB connection – CI-V and accessory connection on radio ICOM 7000 multimode radio ACC Computer Sound Card Connection & USB Control Connection RIGblaster TNC Sound, control, CI-V link CW and digital modes CI-V

Sunspot Values Continue to Decline Reduce propagation at 20 M and above • Sunspots affection ionization • Ionosphere refract radio waves – Bends waves back to earth – Responsible for long range propagation • Declining propagation has reduced our contacts on higher frequencies • CW and digital modes need less SNR than phone Smoothed Sunspot Numbers – Predict Propagation 2008 2009 2010 2011 2012 2013 2014 2015 2016 4. 2 1. 8 9. 3 30. 9 65. 5 58. 7 77. 3 61. 9 44. 8 3. 5 1. 9 10. 6 33. 4 66. 9 58. 4 78. 4 60. 5 43. 2 3. 3 2. 0 12. 3 36. 9 66. 8 57. 6 80. 8 59. 7 41. 4 3. 3 2. 2 14. 0 41. 8 64. 6 57. 9 81. 9 59. 1 39. 4 3. 5 2. 3 15. 5 47. 6 61. 7 59. 9 80. 5 57. 8 37. 5 3. 2 2. 7 16. 4 53. 2 58. 9 62. 6 79. 7 55. 5 36. 6 2017 29. 2 19. 6 28. 6 27. 9 27. 3 26. 7 25. 8 24. 5 23. 0 21. 8 20. 9 20. 2 2018 18. 8 10. 7 17. 7 16. 7 15. 5 14. 5 13. 7 13. 4 13. 1 12. 5 11. 8 11. 1 2019 10. 1 10. 2 2020 10. 5 9. 6 9. 3 9. 0 8. 9 9. 2 9. 5 9. 8 10. 8 11. 3 11. 7 12. 3 13. 2 2. 8 3. 6 16. 8 57. 2 57. 8 65. 5 78. 6 53. 1 35. 9 13. 9 2. 7 4. 8 17. 4 59. 0 58. 2 68. 9 75. 6 51. 2 35. 4 14. 5 2. 3 6. 1 19. 6 59. 5 58. 1 73. 0 70. 8 49. 7 34. 7 15. 2 1. 9 7. 1 23. 2 59. 9 58. 6 74. 9 67. 3 48. 6 33. 5 16. 2 17. 6 1. 7 8. 3 28. 8 63. 4 59. 6 75. 9 63. 7 46. 1 30. 1 19. 0 Next few years will be lower than last few years • To maintain higher contacts need to – Use modes that need less SNR • CW would be best – Use lower frequency bands • 80 and 40 meters 1. 8 7. 6 26. 5 61. 1 59. 7 75. 3 65. 4 47. 4 31. 8 2017

Questions? Thoughts?