Presentation made at Yahoo Open Hack Day Bangalore , 30th July 2011

1. Hacking Amateur Radio with Free Software Debansu Saha VU2DEF [email_address]

2. Prof. J. C. Bose – demonstrated first radio wave propagation at Town Hall, Kolkata in 1894 -95 . He produced millimeter wave to ring a bell . (source Wikipedia) Two years later Marconi demonstrated his wireless at Salisbury Plain in 1897. Here Comes Radio

3. The Spectrum at a Glance Frequency Designation Abbreviation 3 - 30 Hz Extremely low frequency ELF 30 - 300 Hz Super low frequency SLF 300 - 3000 Hz Ultra low frequency ULF 3 - 30 kHz Very low frequency VLF 30 - 300 kHz Low frequency LF 300 kHz - 3 MHz Medium frequency MF 3 - 30 MHz High frequency HF Zone of interest 30 - 300 MHz Very high frequency VHF 300 MHz - 3 GHz Ultra high frequency UHF

4. Amateur’s Share of the Spectrum Abbreviation Frequency Range Bandwidth MF 1260 – 1300 KHz 40 KHz MF 1820 – 1860 KHz 40 KHz HF 3300 – 3400 KHz 100 KHz HF 3890 – 3900 KHz 10 KHz HF 5725 – 5840 KHz 115 KHz HF 7000 – 7100 KHz 100 KHz HF 14000 – 14350 KHz 350 KHz HF 18068 – 18168 KHz 100 KHz HF 21000 – 21450 KHz 450 KHz HF 24890 – 24990 KHz 100 KHz HF 28000 – 29700 KHz 1700 KHz VHF 144 – 146 MHz 2000 KHz UHF 434 – 438 MHz 2000 KHz

5. Amateur Modes and Activities Mode (Modulation Method) Where it can happen Typical Use CW HF, VHF and UHF Ragchewing, Contesting, Traffic and Satellites AM HF Ragchewing AM SSB HF, VHF, UHF Ragchewing, Contesting, Traffic and Satellites FM HF, VHF, UHF Ragchewing, Contesting, Repeaters Digital HF, VHF, UHF Ragchewing, Messg Handling, Data networking, Satellites Image HF, UHF Ragchewing

7. HF Radio with serial / com port interface

8. Computer with sound card and serial / parallel port

12. TNC ( terminal node controller )

13. GNU / Linux computer with AX.25 kernel support and multiple serial ports

15. Low cost radio gives you 1200 baud, costlier ones reach upto 19200 baud.

16. Use APRS ( Automatic Position Reporting System ) . Lets see Xastir

17. Enter the world of Software Defined Radio ( SDR)

19. Software defines the transmitted waveforms and software demodulates the received waveforms

20. Potential to build de-centralized communication system

23. An Universal Software Radio (USRP) Board

24. Couple of USRP daughter card

26. Universal Software Radio Peripheral Now Lets see the Hello world in GNU Radio Companion

28. GNU Radio : http://gnuradio.org

29. Fldigi : http://www.w1hkj.com/FldigiHelp/Modes/index.htm

30. Universal Software Radio Peripheral on Wiki http://comsec.com/wiki?UniversalSoftwareRadioPeripheral

31. Thank You ! 73's