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Moonbounce； Meteor Scatter and Sporadic E propagation。
〃In 1965〃 George told me； 〃I was the only SV station equipped for
contacts via meteor scatter so it was easy for me to make contacts with
many European stations。 The longest distance I achieved was with
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The dawn of amateur radio in the U。K。 and Greece ： a personal view
UA1DZ a Physics Professor at the University of Leningrad in the Soviet
Union。〃
Norman： 〃Forgive me for interrupting you； but please explain in
simple terms what you mean by meteor scatter。〃
George： 〃Meteor scatter is a way of making contacts on 2 metres by
reflection from meteorites … ‘shooting stars' as they are called colloquially
… which we see on clear nights during the summer。 Of course they are not
falling stars at all … they are meteorites which burn up when they hit the
earth's atmosphere； leaving the trail that we see。 We take advantage of this
phenomenon for bouncing our signals off the trail but unfortunately it is a
very short…lived event。 Once when there were a lot of meteorites I was
able to maintain contact with LX1SI of Luxembourg for a whole three
minutes on SSB。 It was during the period of the Persides which usually
occur for a week in August when the earth's orbit takes it through this
cloud of space debris。 Millions of meteorites can be as small as a grain of
sand and of course leave no visible trail when they strike the earth's
atmosphere。 The earth goes through other major clusters in April and in
December。 The phenomenon can also affect signals on lower frequencies。
One can be in QSO on 20 metres via ground wave with a station a couple
of hundred miles away with signals around s2 to s3。 Suddenly one or two
words are heard at s9 which indicates a momentary reflection off a
meteorite trail。〃
George also explained that in order to defeat the brevity of the time
when communication was possible it was customary to record a message
on a tape recorder and transmit it at high speed。 The other station would
also record at high speed and then play back at normal speed to hear the
message normally。
I asked SV1AB to tell me about Sporadic E propagation。
〃In this form of contact the signals are reflected from an ionised area
90 to 120 kilometres above the surface of the earth。 I have been having
contacts by this method for about 18 years now even before the advent of
SSB on two metres。 I have had contacts with England and with Moscow to
the north…east of Athens。 The phenomenon occurs for three or four months
during the summer； and never during the winter。 The ionisation moves
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The dawn of amateur radio in the U。K。 and Greece ： a personal view
very rapidly sometimes … you may be talking to a station in Malta and he
suddenly disappears and a station in Yugoslavia comes up on the same
frequency。〃
〃Every summer〃 George continued； 〃we get Troposcatter which
allows communication on all frequencies from VHF to 10 GHz even。 This
type of propagation occurs during certain special meteorological
conditions； like high barometric pressure and extreme heat。 We sometimes
hear stations in Malta and Sicily with very loud signals。〃
〃In 1966 I built an aerial array consisting of 8 nine…element Yagis for
2 metres with the axis of rotation pointing to the North Star enabling me to
track the Moon automatically。 I was hoping to make some Moonbounce
contacts； but at that time it was very difficult to construct low noise
preamplifiers。 After many days and hours of trying I managed a single
brief contact with F8DO in France。 Some time later I heard that Mike
Staal K6MYC had heard me in California。
〃The funny thing about this aerial array was that it enabled me to
receive television signals from Nigeria on Channel 3 but only when I
raised it up to an elevation of nearly 90 degrees。〃
Norman： 〃I understand that Costas Georgiou SV1OE is the only
Greek amateur who has had successful QSOs via Moonbounce。〃
George： 〃Yes indeed。 But it was many years later； using a low noise
GASFET preamplifier。 K1WHS in the U。S。A。 has an array consisting of
48 Yagis which enable him to contact stations with more modest
installations。
〃In 1970 a technician from Stanford University came to Athens
because the tracking station they had set up on Mount Pendeli could not
pick the University's satellite； whereas they were getting good signals
from it in Spain。 One of the assistants at the station told the American that
he knew an amateur who could pick up signals from satellites； meaning
me。 The American； who happened to be an amateur himself； immediately
asked to see me。 When he saw my 8 antenna array he suggested we should
use it to try and pick up the University satellite。 I pointed out to him that
my array was for 144 MHz whereas the satellite beacon was transmitting
on 136 MHz。 He gave me the coordinates for the next pass and I rotated
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The dawn of amateur radio in the U。K。 and Greece ： a personal view
and raised my array in anticipation。 When the exact time arrived my
modest receiver picked up the satellite beacon loud and clear。 The
American got so excited he asked me if he could use my telephone to call
the University in the U。S。A。 He told them the satellite had been heard at
last in Athens； and by an amateur no less。 Later I received a letter from
NASA thanking me for the assistance I had given。 When the American left
he gave me that 50 MHz converter you can see there on the shelf。〃
Norman： 〃Tell me about your contribution to the transequatorial tests
of 1979。〃
SV1AB： 〃I had been in regular contact with ZS6LN on ten metres
long before Costas SV1DH appeared on the scene。 I remember asking
ZS6LN why we should not receive South African stations on 2 metres
when we could hear them so well on 50 MHz。 He had replied that the two
frequencies behaved in a very different manner； but there was no harm in
trying。 He got ZS6PW and ZS6DN interested in the idea； particularly
ZS6DN