the dawn of amateur radio in the u[1].k.(收音机雏形的诞生)-第11节
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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 who had much better aerials and a very good QTH。 He was the
one who stood the better chance of being heard in Greece。 We arranged a
schedule of transmitting and listening every evening。 First they transmitted
and we listened； and then we transmitted and they listened； and contact
was maintained on ten metres。〃
Norman： 〃You said ‘every evening' do you mean that the Sun has
something to do with this type of propagation？〃
George： 〃Most certainly。 All the contacts that were made
subsequently were at least one hour after the relevant part of the
ionosphere was in darkness。〃
George then described how the first signals were heard via
transequatorial propagation。
George： 〃First we heard the beacon on 144。160 MHz set up by Ray
Cracknell ZE2JV in Southern Rhodesia （now Zimbabwe）。 The date was
April 12th 1978 at 18。00 G。M。T。 Ten months later I heard ZS6DN's
automatic beacon with a colossal signal； but he was not at home！ I went to
20 metres and put out a frantic CQ for any station in South Africa but got
no reply。 I returned to the cross…band frequency on 10 metres which we
used regularly for 28/50 MHz QSOs and managed to contact a station in
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The dawn of amateur radio in the U。K。 and Greece ： a personal view
South Africa who was very far away from ZS6DN but who kindly offered
to QSP a message by telephone。 He was told that ZS6DN had gone out but
would be back soon。 I was terrified that the opening would not last long
enough。 But in a few minutes I heard him calling me slowly on CW and
we exchanged reports at 17。20 G。M。T on February 16th 1979。 This was a
new world record for the longest distance on 2 metres
〃Three days earlier； however； when I was not at home； Costas
SV1DH had established the first TEP contact between Greece and South
Africa when he contacted ZS6DN。 As you know； my location is a mere 10
kilometres north of SV1DH's。 I have a tape recording of my QSO with
ZS6DN as well as with ZS6PW whose signals came through a few
minutes later at 17。34 G。M。T。 on that historic evening。（The local time in
Athens was 7。34 p。m。）。Of course the distance record was broken again on
September 17th 1981 when I contacted ZS4BU who is 110 kilometres
further south than ZS6DN。〃
Norman： 〃Were all these contacts only on the key？〃
George： 〃Yes； all the contacts were on CW。 On several occasions we
tried SSB but there was so much distortion that not a single word could be
identified。 TEP has a lot of flutter and fading and as you can hear on the
tapes even the morse comes through like a breathing noise； not a clear tone。
This applies to contacts between Greece and South Africa。 Contacts
between Japan and Australia where the distances involved are smaller；
have been made on SSB。〃
Norman： 〃What about cycle 22？〃
George： 〃see how things go。 If anything is achieved it should be in
1990 or later。 With modern equipment we shall be able to hear signals that
were buried in the noise in 1979。〃
4。 Dr Spyros Tsaltas SV1AT & George Delikaris SV1AM。 （Mobile）。
The first two licensed amateurs to make contact on 2 metres in
Greece were Dr Spyros Tsaltas SV1AT and George Delikaris SV1AM。
They had put together the famous Heathkit ‘TWOER'。 Crystals were
plentiful on the surplus market； but it was not easy to find two of the same
frequency。 SV1AT transmitted on 144。720 and SV1AM on 145。135 MHz。
The first contact took place at 13。30 local time on the 21st of December
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The dawn of amateur radio in the U。K。 and Greece ： a personal view
1963。
A few days later SV1AT had a cross…band QSO with George
Vernardakis SV1AB who was transmitting in the 20 metre band on 14。250
MHz A。M。 as he had not completed his TWOER yet。
At that time SV1AT was the Secretary of the Radio Amateur
Association of Greece。 He suggested to the Committee that the Club
should apply for a temporary licence to be granted to SV1AM enabling
him to transmit from his vehicle while in motion。 The licensing authority
gave the licence 〃for experimental purposes only； and for a period not
exceeding one month〃。
And so it was that the first ‘mobile' QSO took place on 2 metres
between licensed Greek amateurs on the 27th of January 1965 at 19。25
local time。 SV1AM was travelling in his car and SV1AT was at his home
QTH。
5。 Costas Tzezairlidis SV4CG。 （SSTV）。
In 1970 Costas Tzezairlidis SV4CG built a unique electro mechanical
machine using two motors to achieve horizontal and vertical scanning。 He
had found a motor which rotated at 960 R。P。M。 which corresponds to 16
revolutions per second； the exact speed required for the horizontal
scanning。 The speed of the second motor was 1 revolution per second。 The
reciprocal motion was produced by a cam through an 8：1 reduction gear。 A
weight attached to the microscope pulled it back to start the next line。 The
microscope was focussed sharply on the drum carrying the picture to be
transmitted。 Resolution was excellent。
The ‘microscope' consisted of a cardboard tube with a 13 cm focal
length lens at one end and a Philips OAP12 photo…diode at the other with
another lens in front of it。 This primitive microscope produced a picture of
reasonable quality。
For reception SV4CG made a converter using the long persistence P7
c。r。t。 With this set…up Costas had his first SSTV contact on 40 metres with
SV1AB on February 28th 1971。 After that he had many contacts on 7 and
14 MHz as can be seen from the extract from his log。 （The special
commemorative prefix of SZ0 was used by all SV stations during 1971）。
6。 Costas Georgiou SV1OE。 （E。M。E。）
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The dawn of amateur radio in the U。K。 and Greece ： a personal view
Up to the end of 1988 the only Greek amateur who had positively
authenticated Moonbounce contacts was Costas Georgiou SV1OE。 His
very first contact was made in 1982 when he contacted VE7BQH in
Canada on 2 metres。 In the ensuing four years Costas managed to work
four more stations： K1WHS； SM4GVF； W5UN and KB8RQ。
In 1982 Costas had been trying for three years； without success； to
hear his own signal via Moonbounce。 The reason for his failure was that
he was unaware of a very basic fact。
〃I was completely ignorant of the Doppler shift effect〃； Costas told
me。 〃The frequency of received signals varies according to the position of
the moon。 If it is to the East of your own location the signals return 500 to
1；000 Hz below the original transmitted frequency。 For years I had been
sending long dashes slowly and waiting to hear my signals return on the
same spot； which they never did。 This happens for one instant only； when
the Moon is at 180 degrees azimuth； exactly due south。 When it moves to
the west of south the returning frequency is correspondingly higher。 Using
a 50Hz audio filter （which is essential for Moonbounce） it is very easy to
