the dawn of amateur radio in the u[1].k.(收音机雏形的诞生)-第12节
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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
days of amateur radio in Russia and the story of the Greek broadcasts from
Cairo； Egypt during the German/Italian occupation of Greece in World
War II。
Nearly all the photographs of the period were taken by the author。
1。 Athanasios 'Takis' Coumbias （1909…1987）
When I met Takis in his office in May 1983 I told him I was thinking
of writing a small book about the history of amateur radio in Greece
before it was too late so many of the old timers had already passed away。
Little did we both suspect at the time that he also would not live to see the
finished project。 I asked him how far back he could remember。
〃Well； I can start from 1924 when I was about 15 and living in
Odessa in the Soviet Union。 There was a lot of interest in wireless and two
magazines were published in Russia which dealt mainly with the
construction of receivers。 My interest was first aroused when a friend of
mine at school proudly showed me something he had just made。 It was； he
told me； a variable capacitor and he was going to use it to make a radio
receiver。 The contraption was enormous by today's standards and must
have weighed about half a kilo。 My friend said it had a capacity of 250
micro…micro farads； which meant absolutely nothing to me at the time。
〃When he completed his receiver I became very interested and
decided I would build one too。 But materials were hard to find and very
expensive。 Two items one had to buy： valves and headphones。
〃I asked my friend where he had found the sheet metal to make the
plates of the capacitor。 He took me to a row of small shops which had a
metal…faced ledge below the shop window。 The metal was thin and seemed
easy enough to remove。 We sat on the ledge for a while and when the
coast was clear we tore away a section and ran like mad。 Later I ruined a
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The dawn of amateur radio in the U。K。 and Greece ： a personal view
pair of my mother's dressmaking scissors cutting out the plates。 I used
rings of some thick copper wire to space the plates but I could not drill
holes in the plates for the spindle so a friend did that for me。 I used about
15 plates and to this day I have no idea what the capacity of the finished
capacitor was。 Some small items for the receiver could be found in a little
shop owned by an old man who charged exorbitant prices； so I decided I
must go to Moscow for the valve and a single headphone that I needed。
〃But Moscow was three days and two nights away by train； and it
was the middle of winter。 So what； you may ask。 Like many others I had to
travel on the roof of a goods waggon。 I took with me a loaf of bread； a
piece of cheese and two hard…boiled eggs。 My father said I must be mad
but he gave me some spending money and his blessing。
〃I had eaten my food by the end of the second day so when we
stopped at Brensk which is famous for its 'piroushki' I decided to try them。
They were kept warm in large metal tins ready for the arrival of the train。
There were seven varieties and I had one made with liver and a savoury
sauce。
〃When I arrived in Moscow I went to see the Greek ambassador as I
was carrying a letter of introduction from my father who was acting
Consul for Greece in Odessa； but it was Saturday and the ambassador's
office was closed。 I learned later that only foreign establishments closed at
the week…end。 So I went to look for a cheap hotel。 Looking out of the
bedroom window I saw a lot of people ru
