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Digital QSO: Database vs. Radio Waves - A Debate on Communication Methods

Explore the use of database information over radiowaves for QSO. Discussing standards, theories, and requirements in ham radio communication. Unveil the intricacies of analogue vs. digital transmission methods and the limitations they may bring. Learn about JT65 and the concept of Deep Search in signal communication. Delve into the dependencies of database entry fields and the selection process. Understand the dynamic world of ham radio communication at the Swedish Radio Amateur Society National Convention 2012 in Umeå, Sweden.

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Digital QSO: Database vs. Radio Waves - A Debate on Communication Methods

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  1. Digital QSO – True or False? A discussion about using database information rather than radiowaves for transferring QSO information Swedish Radio Amateur Society National convention 2012 in Umeå, Sweden

  2. Theory and requirements..

  3. Basics: • - a QSO is about transferring information via radiowaves • - a certain standard procedure is used • - callsigns, reports and acknowledgements are exchanged

  4. On VHF and above there are somewhat stricter requirements • for a QSO than on HF. IARU Region 1 VHF Handbook; • definition for a valid QSO on VHF and on higher bands is: • “A valid contact is one where both operators during the • contact have • mutually identified each other • (2) received a report, and • (3) received a confirmation of the successful identification • and the reception of the report.”

  5. IARU Region 1 VHF Handbook says; VALID CONTACTS: “However no recourse should be made during the contact to obtain the required information, change of frequency, antenna direction, etc. via other methods such as the DX Cluster, talk-back on another band, etc.” !

  6. The internationally adopted standard procedure for an EME-QSO says (G3SEK webpage); “Minimum QSO: The definition of a minimum valid QSO is that both stations have copied all of the following: 1. Both callsigns from the other station, 2. Signal report from the other station 3. R from the other station, to acknowledge complete copy of 1 and 2.”

  7. How do we communicate via radiowaves?

  8. Analogue! CW is King!

  9. Analogue! Phone is.. Interesting!

  10. Digital! Digital is.. New! WSJT FSK441/JT65

  11. The digital message FSK441 (G4RGK SM2CEW) 1 001 H 120 2 002 I 121 3 003 J 122 4 010K 123 5 011 L 130 6 012 M 131 7 013 N 132 8 020 O 133 9 021 P 200 . 022 Q 201 , 023 R 202 ? 030 S 203 / 031 T 210 # 032 U 211 <space> 033 V 212 $ 100 W 213 A 101 X 220 B 102 Y 221 C 103 0 223 D 110 E 111 E 230 F 112 Z 231 G 113 JT65 (G4RGK SM2CEW) 100110001111110101000101100100011100111101101111000110101011001 101010100100000011000000011010010110101010011001001000011111111

  12. Det digitala meddelandet FSK441 (G4RGK SM2CEW) 1 001 H 120 2 002 I 121 3 003 J 122 4 010K 123 5 011 L 130 6 012 M 131 7 013 N 132 8 020 O 133 9 021 P 200 . 022 Q 201 , 023 R 202 ? 030 S 203 / 031 T 210 # 032 U 211 <space> 033 V 212 $ 100 W 213 A 101 X 220 B 102 Y 221 C 103 0 223 D 110 E 111 E 230 F 112 Z 231 G 113 Transmitted character by character JT65 (G4RGK SM2CEW) Coded with symbols instead of characters 100110001111110101000101100100011100111101101111000110101011001 101010100100000011000000011010010110101010011001001000011111111

  13. Will this introduce any limitations? ? JT65 100110001111110101000101100100011100111101101111000110101011001 101010100100000011000000011010010110101010011001001000011111111

  14. Yes, it creates limitations.. WSJT Manual: Standard messages are compressed so that two callsigns and a grid locator can be transmitted with just 71 bits.. The aim of source encoding is to compress the common messages used for EME QSOs into a minimum fixed number of bits..

  15. Tables in the software..

  16. Minimal space for the message.. SM2CEW G4RGK IO91

  17. Database..

  18. Let’s take a look at JT65..

  19. Who is calling….??

  20. Add some info in the Setup screen..

  21. That’s better..!?

  22. I’ll write another prefix..

  23. Wow, another DXCC….

  24. I’ll write something else.. Note. FUSK = ”CHEAT” in Swedish

  25. ??….!!

  26. So who is really calling? 072900 9 -7 -0.3 132 5 # SM2CEW OOO 1 0 072900 9 -7 -0.3 132 5 # SM2CEW PJ4/PA3CFH OOO 1 0 072900 9 -7 -0.3 132 5 # SM2CEW 9X5/PA3CFH OOO 1 0 072900 9 -7 -0.3 132 5 # SM2CEW FUSK/PA3CFH OOO 1 0 The truth is that the software is not looking for a call. Instead it is using a flag that says: - Write what the operator entered in the Setup screen 100110001111110101000101100100011100111101101111000110101011001 101010100100000011000000011010010110101010011001001000011111111

  27. The ”Deep Search” concept Or as K1JT says; ”Let’s add 4-6 dB extra sensitivity!”

  28. ”Deep Search” • Very weak signal levels • Can not communicate callsigns • Matching fragments received to database info • Excluding unlikely matches with database info • A qualified guesswork • Does not write on the screen what is received but what the database says

  29. Dependencies: Database Entry fields

  30. Let’s try..

  31. Selection process, who’s not there? PA5M,JO21BS,,,ex PA5MD PA3GST,,,08/03 PA5MS,JO21QJ,EME,,ex PE1OGF,,144: 11el GS35b 400W MGF1302132 4000 DTR,11/02 PA60SHB,JO21OS,,,SpecialCall,,,12/04 PA6BN,JO13OF,,,Expedition - QSL via PA3BIY,,,07/98 PA6MS,JO32QF,,,Special-Call,,DTR,10/96 PA6T,JO32GF,,,Specialcall - QSL via PA2TAB,,DTR 3000lpm,12/98 PA7AL,JO23VG,,,,,,12/04 PA7C,JO32GF,,,ex PA2TAB,,50: 100W 6el - 144: R2CW GS31b 400W 14el MGF1,09/03 PA7FE,JO22OC,,,ex PA3BFM,,50: 6el leg pwr,03/99 PA7FM,JO21,,,ex PE1PZS,,,08/00 PA7PYR,JO21UQ,,,ex PD0PYR,,TS450SAT HF: FB33 - 144: 25W 2x17el Tonna -,09/03 PA7RP,JO22EC,EME,,ex PA3BBA,,144: 400 Watt (GS35b) 17 el F9FT,01/06 PA7WM,JO23TA,,,ex PA3DWD,,,03/99 PA9RX,JO32MT,,,,,144: FT847 4x17el 200W370,08/02 PB0ALS,JO21RV,,,,,,1993 PB1TT,JO22FF,,,ex PA3EFC,,144: 100W 10el CueDee2000lpm DTR,09/01

  32. The ”Deep Search” concept Fragments received, still the computer prints information as if it has been received in full. This is NOT about extra dB’s of sensitivity! No other operator can ”see” a QSO at Deep Search level unless he sets his program up exactly like one of the two stations involved in the QSO and makes sure the info is in the database. Without real time communication (via Internet) you don’t stand much of a chance to complete a QSO where Deep Search is in effect.

  33. Is ”Deep Search” the future? No, not if we want to preserve the radio channel as the carrier of information when making a QSO! Comparing Deep Search with traditional QSO’s is not ok when we know that the callsigns were never transferred via the radio path! DXCC, distance records, locators, fields… all these awards based on true QSO’s are now smeared by allowing Deep Search QSO’s!

  34. The ”Deep Search” concept Let me quote a ”successfull” German moonbouncer with a small EME-array consisting of two short yagis: ”the way to get a small station in the log is to set the sync negative, and switch on "Agressive decode". Then you just have to sit back and wait for the right call to pop up. After that, you can put the parameters back to default.” Yes, he has the 2m DXCC-award his schack wall..

  35. Is ”Deep Search” the future? • If so, what is the next lower limit? • shorthand calls? ” * # ” • detecting a carrier? ” – ” • a time stamp will represent a call • ”120428154523 GMT” = SM2CEW • Not much different from todays Deep Search..

  36. SM2CEW says: - Keep the old concept where QSO information is transferred via radio waves - Do not compare database generated text with a real QSO - Continue experimenting with digital protocols and digging in the noise for real information!

  37. CW is King! Thanks for the attention, see you on the bands!

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