The Next Generation of The Next Generation of Amateur Beacons for the Amateur Beacons for the

2121stst Century Century

Andy Talbot G4JNT / G8IMRAndy Talbot G4JNT / G8IMRwww.scrbg.org/g4jnt

What do we want beacons for ?What do we want beacons for ?Propagation MonitorPropagation 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 checkReceiver confidence check I can’t hear anyone, is it working?I can’t hear anyone, is it working? Frequency CalibrationFrequency Calibration Antenna and Bearing setupAntenna and Bearing setup

What do we have nowWhat do we have now

HF Beacons HF Beacons IARU Beacon chainIARU Beacon chain

• 14 - 28MHz, time sequenced14 - 28MHz, time sequenced• Poor frequency stability / accuracyPoor frequency stability / accuracy

Others on dedicated frequencies >14MHzOthers on dedicated frequencies >14MHz VHFVHF

Hundreds around the worldHundreds around the world Simple crystal control, freq +/- tens of ppm.Simple crystal control, freq +/- tens of ppm.

Microwave BeaconsMicrowave Beacons

Frequency calibrationFrequency calibration

Dish and Bearing setup for /P operationDish and Bearing setup for /P operation

Propagation MonitoringPropagation Monitoring

ImprovementsImprovements

Automatic Monitoring using PC / Automatic Monitoring using PC / SoundcardsSoundcards Narrow band Narrow band Good frequency stabilityGood frequency stability

Frequency ReuseFrequency Reuse Time sequencedTime sequenced

• Help QRM and regulatory issuesHelp QRM and regulatory issues Simplifies auto-monitoring of multiple beaconsSimplifies auto-monitoring of multiple beacons

• No Retuning No Retuning

Next Generation HFNext Generation HF Frequency StabilityFrequency Stability

Aim for better than 10Aim for better than 10-7-7 at HF (+/-1 Hz) at HF (+/-1 Hz) TCXO or Ovened oscillatorTCXO or Ovened oscillator

Minimise frequency clutterMinimise frequency clutter Time sequence - like the IARU chainTime sequence - like the IARU chain

Change the rules to allow beacons below Change the rules to allow beacons below 7MHz7MHz Precise timed transmissionsPrecise timed transmissions Single frequency on each band, worldwide ?Single frequency on each band, worldwide ?

Data ModesData Modes

PSK31 or RTTY could carry informationPSK31 or RTTY could carry information Propagation state, band openingsPropagation state, band openings Site telemetrySite telemetry Unique time signature confirms receptionUnique time signature confirms reception Time / Temperature / Pressure / ???Time / Temperature / Pressure / ???

Next Generation VHFNext Generation VHF Frequency accuracy Frequency accuracy

Ovened crystal or GPS lockedOvened crystal or GPS locked Look for 10Look for 10-9-9 accuracy (sub Hz) for auto accuracy (sub Hz) for auto

searchsearch Add weak signal data modesAdd weak signal data modes

JT65 JT65 Extended period of coherent carrier for Extended period of coherent carrier for

very narrow band integrationvery narrow band integration Timed PSKTimed PSK Automatic monitoringAutomatic monitoring

Microwave BeaconsMicrowave Beacons

Frequency accuracy is importantFrequency accuracy is important Often used as calibrationOften used as calibration Aim for everyone to hear at least one on Aim for everyone to hear at least one on

each band each band Personal beaconsPersonal beacons Attended or unattendedAttended or unattended Licensing easier at microwavesLicensing easier at microwaves

Some Examples of next-Some Examples of next-generation beacons are generation beacons are

already out there….already out there….

The 5MHz beacon chainThe 5MHz beacon chain GB3RAL GB3WES GB3ORK transmit GB3RAL GB3WES GB3ORK transmit

in sequence. Each is on for 1 minute in sequence. Each is on for 1 minute every 15 every 15

GPS timedGPS timed Power steps for audible S/N estimationPower steps for audible S/N estimation TCXO frequency control (few Hz)TCXO frequency control (few Hz) The system was designed for automatic The system was designed for automatic

logging (G3PLX software)logging (G3PLX software) Sounder sequenceSounder sequence

5MHz Automatic Propagation Monitor5MHz Automatic Propagation Monitor

GB3SSS 1960kHz / 3597kHzGB3SSS 1960kHz / 3597kHz Temporary beacon for winter transatlantic Temporary beacon for winter transatlantic

propagation tests.propagation tests. 1 Nov to end Jan 2007 on 1960kHz1 Nov to end Jan 2007 on 1960kHzNEW NEW Nov 2007 – 2008 on 3597kHz Nov 2007 – 2008 on 3597kHz Sequence similar to the 5MHz beacons Sequence similar to the 5MHz beacons

Each 15 minutes, power steps, carrierEach 15 minutes, power steps, carrier PSK31 message instead of sounder PSK31 message instead of sounder All waveforms generated by softwareAll waveforms generated by software CW Keying now has shaped rise timeCW Keying now has shaped rise time

GB3VHF 144.43MHz GB3VHF 144.43MHz Wrotham, KentWrotham, Kent

GPS Controlled frequency and timeGPS Controlled frequency and time JT65, CW, 1pps PSKJT65, CW, 1pps PSK Two minute repeat cycleTwo minute repeat cycle Generic beacon driver conceptGeneric beacon driver concept

Up to 16 thirty second time slots can each be Up to 16 thirty second time slots can each be allocated to different modesallocated to different modes

RTTY message not used on GB3VHFRTTY message not used on GB3VHF

New GB3RAL VHF BeaconsNew GB3RAL VHF Beacons

40.05 / 50.05 / 60.05 / 70.05MHz40.05 / 50.05 / 60.05 / 70.05MHz Non amateur bands for special propagation Non amateur bands for special propagation

monitoring.monitoring. All identical design – All identical design – enhanced GB3VHFenhanced GB3VHF

AD9852 DDSAD9852 DDS GPS timed, every 15 minutesGPS timed, every 15 minutes Master 250MHz clock, GPS lockedMaster 250MHz clock, GPS locked

Bell Hill Microwave BeaconsBell Hill Microwave Beacons

Single site cluster of seven beacons for 2.3 Single site cluster of seven beacons for 2.3 to 47GHz and telemetry Tx on 70MHzto 47GHz and telemetry Tx on 70MHz

Evolutionary upgrades in capabilityEvolutionary upgrades in capability So far, two are GPS locked with RTTY data So far, two are GPS locked with RTTY data

messagemessage GB3SCF 3400.90499999985 MHzGB3SCF 3400.90499999985 MHz GB3SCX 10368.9050068 MHzGB3SCX 10368.9050068 MHz Others will followOthers will follow

Much already existsMuch already exists Driver / oscillator Driver / oscillator (frequency may need stabilising)(frequency may need stabilising) Power Amplifier (+ filters etc)Power Amplifier (+ filters etc) AntennaAntenna

But several new modules are neededBut several new modules are needed Agile Frequency SourceAgile Frequency Source Controller / keyerController / keyer Timing – eg GPSTiming – eg GPS

Beacon HardwareBeacon Hardware

Power AmplifierPower Amplifier

Power Steps, PSK31 etc need a linear PAPower Steps, PSK31 etc need a linear PA For low duty cycle time sequenced, simple For low duty cycle time sequenced, simple

class A or A/B MOSFET design is idealclass A or A/B MOSFET design is ideal Broadband – so useable over multiple bandsBroadband – so useable over multiple bands

• Probably need switched filtersProbably need switched filters High duty cycle with no linear modesHigh duty cycle with no linear modes

Class C design is better suited. Class C design is better suited. Particularly at VHF / UHFParticularly at VHF / UHF Frequency MultiplicationFrequency Multiplication

Simple 10 Watt linear PA for HF beaconsSimple 10 Watt linear PA for HF beacons

Frequency SourcesFrequency Sources Crystal oscillator Crystal oscillator

Single frequency, no data modesSingle frequency, no data modes Poor Frequency StabilityPoor Frequency Stability Use oven or clip-on heaterUse oven or clip-on heater

DDSDDSDirectly useable at HF and low VHFDirectly 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 modesDirect generation of most data modes Clock from standard frequency reference (10MHz)Clock from standard frequency reference (10MHz)

DDS SourcesDDS Sources Older AD9850 / 9851Older 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 useSmall and simple to use 32 bit frequency register32 bit frequency register ~ 10~ 10-9-9 freq setting freq setting Internal x6 PLL for clock Internal x6 PLL for clock

AD9852 / 9854AD9852 / 9854 Up to 90MHz directlyUp to 90MHz directly Amplitude / phase / frequency changed in Amplitude / phase / frequency changed in μsμs 48 Bit - 48 Bit - 1010-14 -14 Frequency setting Frequency setting X4 – X20 Internal clock PLL X4 – X20 Internal clock PLL

Even Faster devices eg. AD9950Even Faster devices eg. AD9950

ControllerController

Microcontroller eg. PICMicrocontroller eg. PIC Standard workhorse 16F84 or 16F628 has Standard workhorse 16F84 or 16F628 has

enough power for most controller tasksenough power for most controller tasks Re-programme the DDS in real time to Re-programme the DDS in real time to

generate data modes generate data modes AD9852 100μs to reprogramme (serial)AD9852 100μs to reprogramme (serial) PSK31, JT65, FSK441 and RTTY PSK31, JT65, FSK441 and RTTY

demonstrated already. demonstrated already. Accept external data / telemetry inputsAccept external data / telemetry inputs

TimingTiming GPS moduleGPS module

Any version will give 1 PPS and timing dataAny version will give 1 PPS and timing data NMEA or native binary NMEA or native binary

Jupiter Navman family have 10kHz output Jupiter Navman family have 10kHz output Allows simple frequency locking using a Allows simple frequency locking using a

synthesizersynthesizer

GB3VHF GB3VHF

GPS Module

DDS SourcePIC Controller

GPS Disciplined Reference (12.8MHz)

A Few Ideas for the A Few Ideas for the FutureFuture

Timestamp the transmission with a Timestamp the transmission with a unique codeunique code

Verifies correct reception at any given date / time.Verifies correct reception at any given date / time. Only the keeper knows the hashing key, and can verify Only the keeper knows the hashing key, and can verify

correct reception.correct reception. Simple to do in a PIC from the GPS data.Simple to do in a PIC from the GPS data.

Alphanumeric code with pronounceable triads :-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 CUF1820 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 TAD1830 TOD 1831 MUG 1832 HUD 1833 CYG 1834 TAD 1835 MEG 1836 FAF 1837 ZEH 1838 WIF 1839 NOH1835 MEG 1836 FAF 1837 ZEH 1838 WIF 1839 NOH

Or Just Keep It Simple !!Or Just Keep It Simple !!

DFCWiDFCWi Audio CW type tones, Audio CW type tones,

• Equal length dot / dash on different freqsEqual length dot / dash on different freqs• Third idle tone Third idle tone

View on SpectrogramView on Spectrogram Listen !Listen !