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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
miss the weak signals。 Soon after I found out my ridiculous mistake I
began to hear my signals； naturally with a delay of one or two seconds
because of the enormous distance involved 770；000 kilometres； 385；000
there and 385；000 back。
Costas continued： 〃My next problem was finding the moon。 I had no
computer at the time and no Keplerian elements。 I mounted a small video
camera in the centre of four 16…element Yagi antennas and rotated the
elevation and azimuth motors until I could see the moon in the centre of
the monitor in the shack。 Of course when the sky was overcast I was out of
business。 Much later when I obtained a little Sinclair ZX80 computer life
became easier。
〃When I made my first contact I was simultaneously in QSO with
SV1AB and SV1IO on 1；296 MHz who could hear what was going on。 I
remember SV1AB got very excited and began shouting ‘I can hear him； I
can hear him！' The QSO was with VE7BQH。 Later Lionel sent me a very
valuable present； valuable not for its cost but for the fact that it was
something quite unobtainable in Greece at that time a very low…noise
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The dawn of amateur radio in the U。K。 and Greece ： a personal view
preamplifier for 2 metres。
〃After the successful launch of Oscar 10 those amateurs who had
complex antenna systems and low…noise receivers they had used for
Moonbounce congregated on 145。950 and spoke to each other on QRP
which prevented ordinary mortals from hearing them。 By QRP I mean
outputs of half a watt or less。 But when finally one day I broke into a net
QSO I arranged schedules for Moonbounce with two stations in Sweden。 I
had a successful contact with one of them but never heard the other。 The
reason may have been a very simple one： the polarisation of signals
returning from the Moon varies from one moment to the other； so if you
have been transmitting with horizontal polarisation and go over to
reception it is very easy to miss the answer of the other station if the
polarisation has changed。〃
SV1OE then explained the very strict procedure which must be
adhered to for Moonbounce schedules。
〃Schedules are arranged to last one hour。 The first station to start
transmitting on the hour must be the one whose QTH lies to the east of the
other。 The calling frequency for Moonbounce is 144。011 MHz。； and the
duration of the call is 2 minutes； but for the first minute and a half you call
CQ DE SV1OE and during the last half minute you also give the call of
the station you are trying to contact； for instance G3FNJ DE SV1OE。 You
must on no account transmit for more than two minutes because at the
beginning of the third minute the other station will begin transmitting the
same pattern of signals。 But if he has heard you he will alter the pattern。
For the first half minute he will send SV1OE DE G3FNJ and for the
ensuing minute and a half he will transmit the letter O which signifies that
he has heard your callsign completely and without difficulty i。e。 Q5 in the
Q Code。 If I have also heard your callsign completely I will send G3FNJ
for half a minute followed by RO for a minute and a half； which means
that I have also received your callsign and your O。 And you will reply RO
73 which concludes the successful contact。
〃There are one or two other letters that can be used。 Sending M
signifies that I hear you well but can only copy 50％ of your transmission；
equivalent to Q3。 And the letter T signifies I hear you but cannot read you
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The dawn of amateur radio in the U。K。 and Greece ： a personal view
at all … Q1。
〃It has been found by experience that the best sending speed is 8
w。p。m。 Sending slowly or very fast presents problems at the other end。〃
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The dawn of amateur radio in the U。K。 and Greece ： a personal view
CHAPTER EIGHT
PERSONAL REMINISCENCES AND ANECDOTES
The eight items which follow are not strictly part of the story of the
development of amateur radio； but they deal with some historical events
which are connected with our hobby。 Two are of particular interest： the
account given to me by Takis Coumbias formerly SV1AAA of the early