the dawn of amateur radio in the u[1].k.(收音机雏形的诞生)-第10节
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tests； as well as amateurs in other areas of South Africa。
It can be seen from the world map that the magnetic dip （shown as a
heavy line） is very different to the geographic equator。 The QTH of
SV1AB is in a suburb 10 kilometres north of SV1DH's so George's
contacts with the stations in Africa always had that edge on them。
In South Africa Dave Larson ZS6DN had set up a beacon which was
first heard in Athens by SV1AB in February 1979。 Within a few days
ZS6DN had QSOs with SV1DH and SV1AB。 The latter contact was a
world distance record via the F…regions of the ionosphere because of the
extra distance involved owing to the locations of the two Greek stations；
as mentioned in the previous paragraph。
For anyone who may be interested very comprehensive reports of the
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The dawn of amateur radio in the U。K。 and Greece ： a personal view
work done in transequatorial propagation during cycle 21 and earlier
appeared in articles written by Ray Cracknell ZE2JV/G2AHU and Roland
Whiting 5B4WR/G3UYO in the June/July/August 1980 issues of Radio
Communuication； the journal of the R。S。G。B。 and in the
November/December 1980 issues of QST。
RECORD TRANSEQUATORIAL PROPAGATION CONTACTS
DURING SUNSPOT CYLE 21
Stations MHz Date GMT Km
YV5ZZ/6 … LU1DAU 145。9 29/10/77 02。00 5；000~ World record
distance on 144 MHz。 First Western hemisphere contact。
JH6TEW … VK8WJ 144。1 10/02/78 11。50 5；060~ First Pacific area
contact。
KP4EOR … LU5DJZ 145。1 12/02/78 00。12 6；340 New world distance
record on 144 MHz。
YV5ZZ … LU3AAT 432。1 13/02/78 01。10 5；100 First reception of 432
MHz signals in Western hemisphere。
5B4WR … ZE2JV 144。1 10/04/78 17。40 5；800 First T。E。P。 contact
between Europe and Africa。
SV1AB … ZE2JV 144。1 12/04/78 18。00 6；260 First Greek distance
record on 144 MHz。
SV1DH … ZS6DN 144。1 13/02/79 18。15 7；120 New world distance
record on 144 MHz。
SV1DH … ZE2JV 432。3 20/03/79 18。20 6；250 First reception of 432
MHz signals between Europe and Africa。
I4EAT … ZS3B 144。1 31/03/79 18。50 7；890 World distance record
（reception） on 144 MHz。
3。 George Vernardakis SV1AB。 （V。H。F。）
In March 1988 I visited George Vernardakis SV1AB （formerly F9QN
of Marseilles； France） who spoke to me about his contribution to the
transequatorial tests and his other experiments in connection with
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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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
