1. The Next Generation of Amateur Beacons for the 21 st Century Andy Talbot G4JNT / G8IMR www.scrbg.org/g4jnt

2. What do we want beacons for ?  Propagation Monitor Band openings, but there’s nobody on! Band openings, but there’s nobody on! Is there anybody out there? Is there anybody out there? Is the band dead? Is the band dead?  Receiver confidence check I can’t hear anyone, is it working? I can’t hear anyone, is it working? Frequency Calibration Frequency Calibration Antenna and Bearing setup Antenna and Bearing setup

3. What do we have now  HF Beacons IARU Beacon chain IARU Beacon chain 14 - 28MHz, time sequenced14 - 28MHz, time sequenced Poor frequency stability / accuracyPoor frequency stability / accuracy Others on dedicated frequencies >14MHz Others on dedicated frequencies >14MHz  VHF Hundreds around the world Hundreds around the world Simple crystal control, freq +/- tens of ppm. Simple crystal control, freq +/- tens of ppm.

4. Microwave Beacons  Frequency calibration  Dish and Bearing setup for /P operation  Propagation Monitoring

5. Improvements  Automatic Monitoring using PC / Soundcards Narrow band Narrow band Good frequency stability Good frequency stability  Frequency Reuse Time sequenced Time sequenced Help QRM and regulatory issuesHelp QRM and regulatory issues Simplifies auto-monitoring of multiple beacons Simplifies auto-monitoring of multiple beacons No RetuningNo Retuning

6. Next Generation HF  Frequency Stability Aim for better than 10 -7 at HF (+/-1 Hz) Aim for better than 10 -7 at HF (+/-1 Hz) TCXO or Ovened oscillator TCXO or Ovened oscillator  Minimise frequency clutter Time sequence - like the IARU chain Time sequence - like the IARU chain  Change the rules to allow beacons below 7MHz Precise timed transmissions Precise timed transmissions Single frequency on each band, worldwide ? Single frequency on each band, worldwide ?

7. Data Modes  PSK31 or RTTY could carry information Propagation state, band openings Propagation state, band openings Site telemetry Site telemetry Unique time signature confirms reception Unique time signature confirms reception Time / Temperature / Pressure / ??? Time / Temperature / Pressure / ???

8. Next Generation VHF  Frequency accuracy Ovened crystal or GPS locked Ovened crystal or GPS locked Look for 10 -9 accuracy (sub Hz) for auto search Look for 10 -9 accuracy (sub Hz) for auto search  Add weak signal data modes JT65 JT65 Extended period of coherent carrier for very narrow band integration Extended period of coherent carrier for very narrow band integration Timed PSK Timed PSK Automatic monitoring Automatic monitoring

9. Microwave Beacons Frequency accuracy is important Frequency accuracy is important Often used as calibration Often used as calibration Aim for everyone to hear at least one on each band Aim for everyone to hear at least one on each band Personal beacons Personal beacons Attended or unattended Attended or unattended Licensing easier at microwaves Licensing easier at microwaves

10. Some Examples of next- generation beacons are already out there….

11. The 5MHz beacon chain  GB3RAL GB3WES GB3ORK transmit in sequence. Each is on for 1 minute every 15  GPS timed  Power steps for audible S/N estimation  TCXO frequency control (few Hz)  The system was designed for automatic logging (G3PLX software)  Sounder sequence

12. 5MHz Automatic Propagation Monitor

13. GB3SSS 1960kHz / 3597kHz  Temporary beacon for winter transatlantic propagation tests.  1 Nov to end Jan 2007 on 1960kHz  NEW Nov 2007 – 2008 on 3597kHz  Sequence similar to the 5MHz beacons Each 15 minutes, power steps, carrier Each 15 minutes, power steps, carrier PSK31 message instead of sounder PSK31 message instead of sounder All waveforms generated by software All waveforms generated by software CW Keying now has shaped rise time CW Keying now has shaped rise time

14. GB3VHF 144.43MHz Wrotham, Kent  GPS Controlled frequency and time  JT65, CW, 1pps PSK  Two minute repeat cycle  Generic beacon driver concept Up to 16 thirty second time slots can each be allocated to different modes Up to 16 thirty second time slots can each be allocated to different modes RTTY message not used on GB3VHF RTTY message not used on GB3VHF

15. New GB3RAL VHF Beacons  40.05 / 50.05 / 60.05 / 70.05MHz Non amateur bands for special propagation monitoring. Non amateur bands for special propagation monitoring.  All identical design – enhanced GB3VHF AD9852 DDS AD9852 DDS GPS timed, every 15 minutes GPS timed, every 15 minutes Master 250MHz clock, GPS locked Master 250MHz clock, GPS locked

16. Bell Hill Microwave Beacons  Single site cluster of seven beacons for 2.3 to 47GHz and telemetry Tx on 70MHz  Evolutionary upgrades in capability  So far, two are GPS locked with RTTY data message GB3SCF 3400.90499999985 MHz GB3SCF 3400.90499999985 MHz GB3SCX 10368.9050068 MHz GB3SCX 10368.9050068 MHz Others will follow Others will follow

17.  Much already exists Driver / oscillator (frequency may need stabilising) Driver / oscillator (frequency may need stabilising) Power Amplifier (+ filters etc) Power Amplifier (+ filters etc) Antenna Antenna  But several new modules are needed Agile Frequency Source Agile Frequency Source Controller / keyer Controller / keyer Timing – eg GPS Timing – eg GPS Beacon Hardware

18. Power Amplifier  Power Steps, PSK31 etc need a linear PA For low duty cycle time sequenced, simple class A or A/B MOSFET design is ideal For low duty cycle time sequenced, simple class A or A/B MOSFET design is ideal Broadband – so useable over multiple bands Broadband – so useable over multiple bands Probably need switched filtersProbably need switched filters  High duty cycle with no linear modes Class C design is better suited. Class C design is better suited. Particularly at VHF / UHF Particularly at VHF / UHF Frequency Multiplication Frequency Multiplication

19.  Simple 10 Watt linear PA for HF beacons

20. Frequency Sources  Crystal oscillator Single frequency, no data modes Single frequency, no data modes Poor Frequency Stability Poor Frequency Stability Use oven or clip-on heater Use oven or clip-on heater  DDS Directly useable at HF and low VHF Spurii need cleaning up for higher frequenciesSpurii need cleaning up for higher frequencies GB3VHF - additional crystal filterGB3VHF - additional crystal filter μWave beacons, lock crystal oscillator to DDS O/PμWave beacons, lock crystal oscillator to DDS O/P Direct generation of most data modes Direct generation of most data modes Clock from standard frequency reference (10MHz) Clock from standard frequency reference (10MHz)

21. DDS Sources  Older AD9850 / 9851 Up to 30MHz directly. Up to 30MHz directly. FM / Phase modulation FM / Phase modulation But no AMBut no AM Small and simple to use Small and simple to use 32 bit frequency register 32 bit frequency register ~ 10 -9 freq setting ~ 10 -9 freq setting Internal x6 PLL for clock Internal x6 PLL for clock  AD9852 / 9854 Up to 90MHz directly Up to 90MHz directly Amplitude / phase / frequency changed in μs Amplitude / phase / frequency changed in μs 48 Bit - 10 -14 Frequency setting 48 Bit - 10 -14 Frequency setting X4 – X20 Internal clock PLL X4 – X20 Internal clock PLL  Even Faster devices eg. AD9950

22. Controller  Microcontroller eg. PIC Standard workhorse 16F84 or 16F628 has enough power for most controller tasks Standard workhorse 16F84 or 16F628 has enough power for most controller tasks  Re-programme the DDS in real time to generate data modes AD9852 100μs to reprogramme (serial) AD9852 100μs to reprogramme (serial) PSK31, JT65, FSK441 and RTTY demonstrated already. PSK31, JT65, FSK441 and RTTY demonstrated already. Accept external data / telemetry inputs Accept external data / telemetry inputs

23. Timing  GPS module Any version will give 1 PPS and timing data Any version will give 1 PPS and timing data NMEA or native binary NMEA or native binary  Jupiter Navman family have 10kHz output Allows simple frequency locking using a synthesizer Allows simple frequency locking using a synthesizer

24.  GB3VHF GPS Module DDS Source PIC Controller GPS Disciplined Reference (12.8MHz)

25. A Few Ideas for the Future

26. Timestamp the transmission with a unique code  Verifies correct reception at any given date / time.  Only the keeper knows the hashing key, and can verify correct reception.  Simple to do in a PIC from the GPS data.  Alphanumeric code with pronounceable triads :- 1800 JIC 1801 PUF 1802 KIC 1803 FOF 1804 WAC 1800 JIC 1801 PUF 1802 KIC 1803 FOF 1804 WAC 1805 PEF 1806 HAR 1807 CEG 1808 LUD 1809 RYG 1805 PEF 1806 HAR 1807 CEG 1808 LUD 1809 RYG 1810 MEB 1811 TAD 1812 CAB 1813 HED 1814 MIB 1810 MEB 1811 TAD 1812 CAB 1813 HED 1814 MIB 1815 TOD 1816 ZUC 1817 FYF 1818 NAC 1819 WEF 1815 TOD 1816 ZUC 1817 FYF 1818 NAC 1819 WEF 1820 PEF 1821 JAH 1822 NAF 1823 WEH 1824 CUF 1820 PEF 1821 JAH 1822 NAF 1823 WEH 1824 CUF 1825 HYH 1826 PIG 1827 WOJ 1828 RAG 1829 LEJ 1825 HYH 1826 PIG 1827 WOJ 1828 RAG 1829 LEJ 1830 TOD 1831 MUG 1832 HUD 1833 CYG 1834 TAD 1830 TOD 1831 MUG 1832 HUD 1833 CYG 1834 TAD 1835 MEG 1836 FAF 1837 ZEH 1838 WIF 1839 NOH 1835 MEG 1836 FAF 1837 ZEH 1838 WIF 1839 NOH

27. Or Just Keep It Simple !!  DFCWi Audio CW type tones, Audio CW type tones, Equal length dot / dash on different freqsEqual length dot / dash on different freqs Third idle toneThird idle tone View on Spectrogram View on Spectrogram Listen ! Listen !