Suggs, Rob

NASA Technical Reports Server

METEOR SCATTER COMMUNICATIONS:
THE SCIENCE BEHIND THE PINGS
DR. ROB SUGGS
KB5EZ
SPACE ENVIRONMENTS TEAM LEAD
NASA/MSFC/EV44
NASA METEOROID ENVIRONMENT OFFICE
MSFC AMATEUR RADIO CLUB NN4SA
KB5EZ@YAHOO.COM
HUNTSVILLE HAMFEST AUGUST 2017
ISS-030-E260480
https://ntrs.nasa.gov/search.jsp?R=20170009030 2019-08-29T23:17:11+00:00Z
OUTLINE
• What is a meteor?
• What scatters my signal?
• Where does my signal go?
• When is the best time to operate?
• What equipment should I use?
• What software and mode should I use?
• What does a QSO look and sound like?
• Tools to help make contacts
• Summary
• An operating event announcement
• Links
Science part
Radio part
}
}
Rob Suggs KB5EZ  August 2017 2
WHAT IS A METEOR?
• Consist of small pieces (grain of sand, particle of dust) of mostly cometary 
(90%) or asteroidal (10%) material
• Meteoroids – bits in space
• Meteors – bits burning up in the atmosphere
• Meteorites – hit the ground
• Visible light from a meteor comes mostly from the ionization of the 
atmosphere
• The free electrons from the ionization can scatter radio signals
• Sporadic meteors come from all over the sky (mostly), all the time but are 
most numerous near sunrise when we are on the front bumper of Earth
• Shower meteors appear to come from a point on the sky called the radiant
• This is a perspective effect – like looking down a railroad track
Rob Suggs KB5EZ  August 2017 3
ALL SKY CAMERA VIEW OF PERSEID 12 AUG 2017
Rob Suggs KB5EZ  August 2017 4
LEONIDS 1999
Rob Suggs KB5EZ  August 2017 5
90% OF METEOROIDS COME FROM COMETS
Rob Suggs KB5EZ  August 2017
Comet Halley 1986
6
COMET HALLEY
• Halley particles are responsible for 2 meteor showers 
every year
Orionids - October
Eta Aquarids - May
Rob Suggs KB5EZ  August 2017 7
COMPUTER MODEL OF LEONID STREAM
Rob Suggs KB5EZ  August 2017 8
IONOSPHERE
Meteor regimeM teo s
Rob Suggs KB5EZ  August 2017 9
WHAT SCATTERS MY SIGNAL?
• As the meteoroid enters the atmosphere at high speed (15 – 70 
km/s) it ionizes the oxygen and nitrogen molecules generating 
ions and free electrons which scatter the RF (also makes light)
• This occurs between about 100 and 80 km, near the same 
altitude as sporadic E (Es) 
• The only relationship between Es and meteors is that the electrons 
responsible for Es are thought to come from metals deposited in the 
atmosphere from meteor ablation.
• But Es is not correlated with meteor showers
• During summer you may work Es while attempting meteor scatter QSOs
• Es gives longer-lasting signals
Rob Suggs KB5EZ  August 2017 10
170807_024515.wav
6m FT8 Meteor Ping
7 August 2017 02:45:15
TWO TYPES OF METEOR TRAILS
Underdense
• Weak echoes
• Short-lived (<1 second) 
• Electron density is so low that individual 
electrons don’t interact with each other)
• Scattering geometry must be specular
Overdense
• Strong echoes
• Long-lived (many seconds)
• Electrons act in concert like a metal tube
• Scattering geometry must be specular but 
upper atmospheric winds can “crinkle the tube”
From P. Brown, Univ. of Western Ontario
A
m
p
lit
u
d
e
Time
A
m
p
lit
u
d
e
Time
Rob Suggs KB5EZ  August 2017 12
UNDERDENSE EXAMPLE
Rob Suggs KB5EZ  August 2017 13
ANOTHER LEONID
Rob Suggs KB5EZ  August 2017 14
Underdense echo
From P. Brown, Univ. of Western OntarioRob Suggs KB5EZ  August 2017
15
Overdense echo
From P. Brown, Univ. of Western OntarioRob Suggs KB5EZ  August 2017
16
APPROXIMATE HOURLY METEOR RATES
Rob Suggs KB5EZ  August 2017 17
RETURN POWER
Important point is that the signal strength goes as the cube of the 
wavelength, l, and the square of the electron line density, q
You want to use the longest wavelength (lowest frequency) possible.  
If you get into HF bands, Ionospheric effects can dominate so lower 
VHF (40 – 100 MHz) is best.   From McKinley, 1961.
Rob Suggs KB5EZ  August 2017 18
FREQUENCY DEPENDENCE
• Since scattered power is proportional to the wavelength3 or 
1/frequency3  let’s compare 2m to 6m
P ≈ (144.2 / 50.26)3 = 23.6 or 13.7 dB, more than 2 S units
• But antenna gain is slightly easier at 2m
• 3 element 6m yagi is 8 dBi (5 element ~ 16 dBi) 
• 11 element 2m yagi ~ 15 dBi
• But most HF rigs have 6m
• So 6m is favored especially if you don’t already have the 
antennas and amplifier for 2m
• 10m should also work but is not typically used – beware 
signaling rate limitations (1200 baud – 10m) below VHF
Rob Suggs KB5EZ  August 2017 19
WHERE DOES MY SIGNAL GO?
TYPICAL RANGE: 800 – 2300 KM (500 – 1400 MI)
Rob Suggs KB5EZ  August 2017 20
WHERE DOES MY SIGNAL GO?
• Meteor must lie tangent to an ellipsoid with the transmitter and receiver at the foci
• This geometry favors certain path directions as the shower radiant moves across 
the sky
• The vast majority of meteors don’t satisfy this ”specular” condition and can’t be 
used for communications
Rob Suggs KB5EZ  August 2017 21
TX RX
WHAT IS THE BEST TIME TO OPERATE?
• Morning – diurnal variation – like bugs on a windshield
• Car (Earth) going 30 km/s
• Bugs (meteoroids) going up to 40 km/s around the sun, some head-on
• Impact speed is vector sum of these – all hit windshield, only really fast 
ones hit rear window
• There are fewer meteors in the spring,  +/- 20% annual variation
• During meteor showers – there are more large meteors
Name Peak Dates Approx. Meteors/hour Speed
Quandrantids Jan. 3 120 43 km/s
Arietids Jun. 9 (daytime) 45 41
Eta Aquariids May 6 60 66
Perseids Aug. 11-13 90 60
Orionids Oct. 20-22 20 67
Geminids Dec. 12-13 120 36
Rob Suggs KB5EZ  August 2017 22
2004 QUADRANTID METEOR SHOWER
Rob Suggs KB5EZ  August 2017 23
Initial radius – why fast meteors 
don’t work as well
Ionization column
Radio signal
Initial 
radius
meteoroid
From P. Brown, Univ. of Western Ontario
Rob Suggs KB5EZ  August 2017 24
Initial radius
When the radius of an underdense trail is of the order 
of the radar wavelength, there is significant attenuation
height
ri
height
at
m
o
sp
h
er
ic
 d
en
si
ty
Initial radius varies 
with height
Since meteor 
ablation heights 
vary with speed 
(faster meteoroids 
ablate higher), the 
initial radius effect 
biases radio against 
fast meteors.
From P. Brown, Univ. of Western Ontario
Rob Suggs KB5EZ  August 2017 25
SPORADIC SOURCE RADIANTS FROM RADAR
Meteoroid Flux as a function of direction as observed by Canadian Meteor Orbit Radar.  
Observationalbiases have been taken into account and results have been weighted by a 
constant limiting kinetic energy.  Coordinate system is Earth-centered ecliptic.
Sun
Direction of Earth’s motion
Rob Suggs KB5EZ  August 2017 26
AntihelionHelion
North Toroidal
North Apex
South Apex
WHAT EQUIPMENT SHOULD I USE?
• Most modern HF rigs include 6m
• Throttle back from max power for high duty cycle like MSK144 (50 -
75%) 
• Antenna gain helps – 5 element beam on 6m is good
• An amplifier and mast-mounted preamp help
• It is possible to make contacts with attic-mounted dipoles – be 
patient and make a sched with a big gun
• Most modern computers have adequate processing power
• May need to reduce Frequency Tolerance (FTOL below 200 Hz)
• Need a soundcard interface 
• Many new rigs have this built-in
• SignaLink is very popular
• Homebrew is fairly simple
Rob Suggs KB5EZ  August 2017
27
WHAT SOFTWARE AND MODE SHOULD I USE?
• WSJT-X has the MSK144 mode which is the standard
• Available for Windows, Mac and Linux
• 15 second cycle is typically used, messages are 72 msec
• Offset quadrature phase shift keying (minimum shift keying)
• PC clock should be set accurately, within a second or so
• The WSJT Yahoogroup is excellent but READ THE MANUAL FIRST
• Previous versions of WSJT had the FSK441 mode which has 
faded from use
• Longer format modes like JT65 and FT8 are too slow
• Recall that most “pings” are a second or two
• CW and SSB are possible but are more difficult
Rob Suggs KB5EZ  August 2017 28
WHAT DOES A QSO LOOK AND SOUND LIKE?
• MSK144 sounds more like a grunt than a ping
• The QSO sequence looks just like JT65/JT9/FT8
• Operators’ choice whether exchanging signal reports or grid 
squares
• Auto Sequence mode of MSK144 makes the QSO easy
Rob Suggs KB5EZ  August 2017 29
LOCAL CONTACT USING MSK144
Rob Suggs KB5EZ  August 2017 30

KG4Q AIRCRAFT SCATTER 12:48 29 MAY
Rob Suggs KB5EZ  August 2017 32
TOOLS TO HELP MAKE CONTACTS
• Pingjockey.net
• Great way to setup a contact
• Agree on frequency and timing
• DO NOT post info during the QSO if you want it to “count”
• University of Western Ontario radar site
• Indicates which showers are active
• 15 kW radar at 17.45, 29.85, and 38.15 MHz
• The system can’t see meteors from radiants directly 
overhead
• It loses sensitivity for higher speed meteors (initial trail 
radius)
Rob Suggs KB5EZ  August 2017 33
PINGJOCKEY.NET
Rob Suggs KB5EZ  August 2017 34
Perseids 12 August 2017
UWO RADAR SITE – FIREBALLS.NDC.NASA.GOV
Perseids 12 August 2017
SUMMARY
• Meteor scatter communications is easier than ever thanks to digital 
modes
• You can make meteor scatter contacts anytime but they are easier 
during meteor showers and during the morning hours
• You don’t need a super station but antenna gain, a preamp, and 
transmit power make it easier
• Try it even if you are running 50w to a dipole
• Don’t be afraid to ask for help on the Pingjockey and WSJT groups but 
do a little homework first
• Get some experience with JT65, JT9 or especially FT8 on HF to get the 
feel for digital contacts and checkout your rig interface
• Give it a try and ponder what is happening when you hear a “ping” –
some dust particle has been wandering around the solar system for 
hundreds or thousands of years and then meets its fiery end to help 
you make a QSO
Rob Suggs KB5EZ  August 2017
37
AN ANNOUNCEMENT – NASA ON THE AIR EVENT
• Beginning this December, 13 club stations at NASA centers and 
facilities will be participating in a year long event: NASA On The Air
• Points can be accumulated by working these club stations on various 
bands and modes, a web-based system will allow points tracking
• A downloadable certificate will be available at the end of the event in 
December 2018
• Various special events will also be celebrated including:
• December 2017 – 45th anniversary of Apollo 17 last lunar landing
• June 2018 – 60th anniversary of NASA
• October 2018 – 20th anniversary of International Space Station
• December 2018 – 50th anniversary of Apollo 8 lunar orbiting mission
• Stay tuned to QST and nasaontheair.wordpress.com for further details
Rob Suggs KB5EZ  August 2017 38
NASA CENTERS AND FACILITIES – PARTICIPATING CLUBS
NA6MF
WA3NAN
KG4NJA
W5RRR
N5BL
NN4SA
N5SSC - Stennis
NA8SA
N1KSC
NA6SA
W6VIO - JPL
W4WFF - Wallops
NA1SS
Rob Suggs KB5EZ  August 2017 39
LINKS AND ADDITIONAL RESOURCES
• https://www.pingjockey.net/cgi-bin/pingtalk
• https://fireballs.ndc.nasa.gov
• https://physics.Princeton.edu/plulsar/k1jt/wsjtx.html
• International Meteor Organization radio observation info  
http://www.imo.net/radio/index.html
• Check NASA Technical Report Server for these slides
• https://www.sti.nasa.gov/
• Meteor Science and Engineering by D. W. R. McKinley –
1961 
Rob Suggs KB5EZ  August 2017 40
BACKUP
Rob Suggs KB5EZ  August 2017 41
PARTICIPATING CLUBS
• Ames Research Center – ARC – NA6MF - California
• Armstrong Flight Research Center – AFRC – NA6SA - California
• Glenn Research Center – GRC – NA8SA- Ohio
• Goddard Space Flight Center – GSFC – WA3NAN – Maryland
• International Space Station – ISS – NA1SS, etc. – earth orbit
• Jet Propulsion Laboratory – JPL – W6VIO – California
• Johnson Space Center – JSC – W5RRR – Texas
• Kennedy Space Center – KSC – N1KSC – Florida
• Langley Research Center – LARC – KG4NJA – Virginia
• Marshall Space Flight Center – MSFC – NN4SA – Alabama
• Stennis Space Center – SSC – N5SSC (to be requested) – Mississippi
• Wallops Fight Facility – WFF – W4WFF – Virginia 
• White Sands Complex/White Sands Test Facility – WSCTF – TBD – New Mexico
Rob Suggs KB5EZ  August 2017 42
Rob Suggs KB5EZ  August 2017
Doppler of head Fade due to wind disruption of trail
Spectrogram of “Bright” and 
“Faint” Meteors
Long
Head
Tropospherically propagated video carrier
Doppler shift from head echo (inverted by receiver)
Overdense meteor echo Underdense meteor echoes
43
Rob Suggs KB5EZ  August 2017 44
FORWARD SCATTER GEOMETRY
From “Meteor Science and Engineering”, D.W.R. McKinley
Rob Suggs KB5EZ  August 2017 45
Perseids 12 August 2017

UWO RADAR SITE - SPEEDS
Rob Suggs KB5EZ  August 2017 48
UWO RADAR SITE – FIREBALLS.NDC.NASA.GOV
Rob Suggs KB5EZ  August 2017
49
Rob Suggs KB5EZ  August 2017 50
Rob Suggs KB5EZ  August 2017 51
Rob Suggs KB5EZ  August 2017 52
Rob Suggs KB5EZ  August 2017 53
FSK 441 GEMINID 2014 CONTACT
Rob Suggs KB5EZ  August 2017
54



Meteor Scatter Communications: The Science Behind the Pings

METEOR SCATTER COMMUNICATIONS:
THE SCIENCE BEHIND THE PINGS
DR. ROB SUGGS
KB5EZ
SPACE ENVIRONMENTS TEAM LEAD
NASA/MSFC/EV44
NASA METEOROID ENVIRONMENT OFFICE
MSFC AMATEUR RADIO CLUB NN4SA
KB5EZ@YAHOO.COM
NORTH ALABAMA DX CLUB OCTOBER 2017
ISS-030-E260480
https://ntrs.nasa.gov/search.jsp?R=20170012398 2019-08-30T16:43:17+00:00Z
OUTLINE
• What is a meteor?
• What scatters my signal?
• Where does my signal go?
• When is the best time to operate?
• What equipment should I use?
• What software and mode should I use?
• What does a QSO look and sound like?
• Tools to help make contacts
• Summary
• Links
Science part
Radio part
}
}
Rob Suggs KB5EZ  October 2017 2
WHAT IS A METEOR?
• Consist of small pieces (grain of sand, particle of dust) of mostly cometary 
(90%) or asteroidal (10%) material
• Meteoroids – bits in space
• Meteors – bits burning up in the atmosphere
• Meteorites – hit the ground
• Visible light from a meteor comes mostly from the ionization of the 
atmosphere
• The free electrons from the ionization can scatter radio signals
• Sporadic meteors come from all over the sky (mostly), all the time but are 
most numerous near sunrise when we are on the front windshield of Earth
• Shower meteors appear to come from a point on the sky called the radiant
• This is a perspective effect – like looking down a railroad track
Rob Suggs KB5EZ  October 2017 3
ALL SKY CAMERA VIEW OF PERSEID 12 AUG 2017
Rob Suggs KB5EZ  October 2017 4
LEONIDS 1999
Rob Suggs KB5EZ  October 2017 5
90% OF METEOROIDS COME FROM COMETS
Rob Suggs KB5EZ  October 2017
Comet Halley 1986
6
COMET HALLEY
• Halley particles are responsible for 2 meteor showers 
every year
Orionids - October
Eta Aquarids - May
Rob Suggs KB5EZ  October 2017 7
COMPUTER MODEL OF LEONID STREAM
Rob Suggs KB5EZ  October 2017 8
IONOSPHERE
Meteor regimeM teo s
Rob Suggs KB5EZ  October 2017 9
WHAT SCATTERS MY SIGNAL?
• As the meteoroid enters the atmosphere at high speed (15 – 70 
km/s) it ionizes the oxygen and nitrogen molecules generating 
ions and free electrons which scatter the RF (also makes light)
• This occurs between about 100 and 80 km, near the same 
altitude as sporadic E (Es) 
• The only relationship between Es and meteors is that the electrons 
responsible for Es are thought to come from metals deposited in the 
atmosphere from meteor ablation.
• But Es is not correlated with meteor showers
• During summer you may work Es while attempting meteor scatter QSOs
• Es gives longer-lasting signals
Rob Suggs KB5EZ  October 2017 10
170807_024515.wav
6m FT8 Meteor Ping
7 August 2017 02:45:15
TWO TYPES OF METEOR TRAILS
Underdense
• Weak echoes
• Short-lived (<1 second) 
• Electron density is so low that individual 
electrons don’t interact with each other)
• Scattering geometry must be specular
Overdense
• Strong echoes
• Long-lived (many seconds)
• Electrons act in concert like a metal tube
• Scattering geometry must be specular but 
upper atmospheric winds can “crinkle the tube”
From P. Brown, Univ. of Western Ontario
A
m
p
lit
u
d
e
Time
A
m
p
lit
u
d
e
Time
Rob Suggs KB5EZ  October 2017 12
UNDERDENSE EXAMPLE
Rob Suggs KB5EZ  October 2017 13
ANOTHER LEONID
Rob Suggs KB5EZ  October 2017 14
Underdense echo
From P. Brown, Univ. of Western OntarioRob Suggs KB5EZ  October 2017
15
Overdense echo
From P. Brown, Univ. of Western OntarioRob Suggs KB5EZ  October 2017
16
APPROXIMATE HOURLY METEOR RATES
Rob Suggs KB5EZ  October 2017 17
RETURN POWER
Important point is that the signal strength goes as the cube of the 
wavelength, l, and the square of the electron line density, q
You want to use the longest wavelength (lowest frequency) possible.  
If you get into HF bands, Ionospheric effects can dominate so lower 
VHF (40 – 100 MHz) is best.   From McKinley, 1961.
Rob Suggs KB5EZ  October 2017
18
Also, the signal duration goes as the square of the wavelength.
FREQUENCY DEPENDENCE
• Since scattered power is proportional to the wavelength3 or 
1/frequency3  let’s compare 2m to 6m
P ≈ (50.26 / 144.2)3 = 1/23.6 or -13.7 dB, more than 2 S units
• But antenna gain is slightly easier at 2m
• 3 element 6m yagi is 8 dBi (5 element ~ 16 dBi) 
• 11 element 2m yagi ~ 15 dBi
• But most HF rigs have 6m
• So 6m is favored especially if you don’t already have the 
antennas and amplifier for 2m
• 10m should also work but is not typically used – beware 
signaling rate limitations (1200 baud – 10m) below VHF
• Can’t use MSK144
Rob Suggs KB5EZ  October 2017 19
WHERE DOES MY SIGNAL GO?
TYPICAL RANGE: 800 – 2300 KM (500 – 1400 MI)
Rob Suggs KB5EZ  October 2017 20
WHERE DOES MY SIGNAL GO?
• Meteor must lie tangent to an ellipsoid with the transmitter and receiver at the foci
• This geometry favors certain path directions as the shower radiant moves across 
the sky
• The vast majority of meteors don’t satisfy this ”specular” condition and can’t be 
used for communications
Rob Suggs KB5EZ  October 2017 21
TX RX
WHAT IS THE BEST TIME TO OPERATE?
• Morning – diurnal variation – like bugs on a windshield
• Car (Earth) going 30 km/s
• Bugs (meteoroids) going up to 40 km/s around the sun, some head-on
• Impact speed is vector sum of these (10 – 70 km/s) – all hit windshield, 
only really fast ones hit rear window
• There are fewer meteors in the spring,  +/- 20% annual variation
• During meteor showers – there are more large meteors
Name Peak Dates Approx. Meteors/hour Speed
Quandrantids Jan. 3 120 43 km/s
Arietids Jun. 9 (daytime) 45 41
Eta Aquariids May 6 60 66
Perseids Aug. 11-13 90 60
Orionids Oct. 20-22 20 67
Geminids Dec. 12-13 120 36
Rob Suggs KB5EZ  October 2017 22
2004 QUADRANTID METEOR SHOWER
Rob Suggs KB5EZ  October 2017 23
SPORADIC SOURCE RADIANTS FROM RADAR
Meteoroid Flux as a function of direction as observed by Canadian Meteor Orbit Radar.  
Observational biases have been taken into account and results have been weighted by a 
constant limiting kinetic energy.  Coordinate system is Earth-centered ecliptic.
Sun
Direction of Earth’s motion
Rob Suggs KB5EZ  October 2017 24
AntihelionHelion
North Toroidal
North Apex
South Apex
Left side Right side BehindBehind
WHAT EQUIPMENT SHOULD I USE?
• Most modern HF rigs include 6m
• Throttle back from max power for high duty cycle like MSK144 (50 -
75%) 
• Antenna gain helps – 5 element beam on 6m is good
• An amplifier and mast-mounted preamp help
• It is possible to make contacts with attic-mounted dipoles – be 
patient and make a sched with a big gun
• Most modern computers have adequate processing power
• May need to reduce Frequency Tolerance (FTOL below 200 Hz)
• Need a soundcard interface 
• Many new rigs have this built-in
• SignaLink is very popular
• Homebrew is fairly simple
Rob Suggs KB5EZ  October 2017
25
Rob Suggs KB5EZ  October 2017 26
NN4SA Club Station
WHAT SOFTWARE AND MODE SHOULD I USE?
• WSJT-X has the MSK144 mode which is the standard
• Available for Windows, Mac and Linux
• 15 second cycle is typically used, messages are 72 msec
• Offset quadrature phase shift keying (minimum shift keying)
• PC clock should be set accurately, within a second or so
• The WSJT Yahoogroup is excellent but READ THE MANUAL FIRST
• Previous versions of WSJT had the FSK441 mode which has 
faded from use
• Longer format modes like JT65 and FT8 are too slow
• Recall that most “pings” are a second or two
• CW and SSB are possible but are more difficult
Rob Suggs KB5EZ  October 2017 27
WHAT DOES A QSO LOOK AND SOUND LIKE?
• MSK144 sounds more like a grunt than a ping
• The QSO sequence looks just like JT65/JT9/FT8
• Operators’ choice whether exchanging signal reports or grid 
squares or usually both
• Auto Sequence mode of MSK144 makes the QSO easy
Rob Suggs KB5EZ  October 2017 28
LOCAL CONTACT USING MSK144
Rob Suggs KB5EZ  August 2017 29

KG4Q AIRCRAFT SCATTER 12:48 29 MAY
Rob Suggs KB5EZ  October 2017 31
TOOLS TO HELP MAKE CONTACTS
• Pingjockey.net
• Great way to setup a contact
• Agree on frequency and timing
• DO NOT post info during the QSO if you want it to “count”
• University of Western Ontario radar site
• Indicates which showers are active
• 15 kW radar at 17.45, 29.85, and 38.15 MHz
• The system can’t see meteors from radiants directly 
overhead
• It loses sensitivity for higher speed meteors (initial trail 
radius)
Rob Suggs KB5EZ  October 2017 32
PINGJOCKEY.NET
Rob Suggs KB5EZ  October 2017 33
Perseids 12 August 2017
UWO RADAR SITE – FIREBALLS.NDC.NASA.GOV
Perseids 12 August 2017
SUMMARY
• Meteor scatter communications is easier than ever thanks to digital 
modes – MSK144 in WSJT-X
• You can make meteor scatter contacts anytime but they are easier 
during meteor showers and during the morning hours
• You don’t need a super station but antenna gain, a preamp, and 
transmit power make it easier
• Try it even if you are running 50w to a dipole
• Don’t be afraid to ask for help on the Pingjockey and WSJT groups but 
do a little homework first
• Get some experience with JT65, JT9 or especially FT8 on HF to get the 
feel for digital contacts and checkout your rig interface
• Give it a try and ponder what is happening when you hear a “ping” –
some dust particle was blown out of a comet and has been wandering 
around the solar system for hundreds or thousands of years and then 
meets its fiery end to help you make a QSO
Rob Suggs KB5EZ  October 2017
36
LINKS AND ADDITIONAL RESOURCES
• https://www.pingjockey.net/cgi-bin/pingtalk
• https://fireballs.ndc.nasa.gov
• https://physics.Princeton.edu/plulsar/k1jt/wsjtx.html
• International Meteor Organization radio observation info  
http://www.imo.net/radio/index.html
• Check NASA Technical Report Server for these slides
• https://www.sti.nasa.gov/
• Meteor Science and Engineering by D. W. R. McKinley –
1961 
Rob Suggs KB5EZ  October 2017 37
BACKUP
Rob Suggs KB5EZ  October 2017 38
Rob Suggs KB5EZ  October 2017
Doppler of head Fade due to wind disruption of trail
Spectrogram of “Bright” and 
“Faint” Meteors
Long
Head
Tropospherically propagated video carrier
Doppler shift from head echo (inverted by receiver)
Overdense meteor echo Underdense meteor echoes
39
Rob Suggs KB5EZ  October 2017 40
FORWARD SCATTER GEOMETRY
From “Meteor Science and Engineering”, D.W.R. McKinley
Rob Suggs KB5EZ  October 2017 41
Perseids 12 August 2017

UWO RADAR SITE - SPEEDS
Rob Suggs KB5EZ  October 2017 44
UWO RADAR SITE – FIREBALLS.NDC.NASA.GOV
Rob Suggs KB5EZ  October 2017
45
Rob Suggs KB5EZ  October 2017 46
Rob Suggs KB5EZ  October 2017 47
Rob Suggs KB5EZ  October 2017 48
FSK 441 GEMINID 2014 CONTACT
Rob Suggs KB5EZ  October 2017
49



Meteor Scatter Communications: The Science Behind the Pings

Abstract

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