Following World War II, the occupation and civil war, the telecommunications network was all but destroyed. With the incorporation of OTE in 1949 and financial aid from the America's Marshall Plan, telephony developed rapidly. At the end of 1955, new connections rose by 60%, reaching 103,200; in other words, OTE installed as many new connections in five years (1950-1955) as AETE managed to install within 19 years (1930-1949). Keeping in line with urbanisation and economic modernisation, telephony continued its expansion in the 1960s, reaching 401,749 subscribers by the end of 1965. The coming decades saw OTE on the rise, with the establishment of new centres, services, ground satellite stations and a constant increase in subscribers. At the turn of the century, in 2000, there were 5,659,274 main telephone lines.

Telephone booths were placed at central locations in Athens and Piraeus in the 1930s. Given that the acquisition of a private telephone was still a luxury for the majority of people, most Athenians preferred to buy a token from the kiosk and make their calls from the “stylish boxes”. As queues outside the city’s centrally-located telephone booths were the norm, telephony symbolised a new, modern sociability where the public and private were intertwined.

In the first decade of OTE’s incorporation (1950-1960), public telephone conversations increased by 51% compared to the previous decade, which demonstrated the importance of public telephones for the social and professional needs of the general public. In the 1980s and early 1990s, public telephony went into decline. The 57th Thessaloniki International Fair in 1992 saw the introduction of the first card-based pay phone and the gradual replacement of the coin-operated pay phones.

The history of the telephone is one of constant transformation. An ongoing effort in the transmission of the human voice with new methods, technological innovations and design changes. The evolution of telephone devices, which is not always perceived by the user, follows the technological advancements, consumer needs and aesthetics of each era.

1890-1900

The first telephones were usually wall-mounted, made of wood and bronze. Necessary components are the manual lever for generating electricity, the hopper connected to the microphone and the handset that hangs from the side of the device.

1910-1930

The first automatic telephones with a rotating dial appear. The devices are gradually becoming metal and desktop. The headphones are made of bronze and are made of bakelite. The design and color of the phone corresponds to the social position of its owner.

1930-1940

The mass-produced W28 models are evolving in parallel with luxury phones. Next to the devices with the gold color coexist the black automatic desktop phones made of bakelite and steel base.

1940-1950

The decade of warfare produced the telecommunications equipment needed in war. Portable military magnetic telephones, military khaki radios, and wireless signal control and transmitters used extensively during the Korean War (1950).

1950-1960

In the 1950s the telephone became a household, decorative object. The devices become colorful and the shape ceases to be so conservative and standard. The telephone is now a consumer good that caters to all tastes and social groups.

1970-1980

The telephone devices of the period are dominated by pop, light aesthetics. The telephone enters millions of homes and must follow fashion. At the same time, the devices with keys that replace the rotating dial disk are displayed.

The first women who were hired as civil servants in Greece were employed at the country’s telegraph offices and switchboards under the law of 1908. The first switchboard operators were young, single, usually with a teaching diploma. They held the lowest rank in the organisational structure, with no prospect of advancement and poor working conditions. According to a memo which the operators addressed to the Parliament, tuberculosis was the operators’ main cause of death.

Their job was to answer telephone calls and, by connecting the appropriate jack to the extension on the switchboard, create a call between two subscribers. Switchboard operators were able to listen in on all conversations that they had activated. A typical example is when Sergei Kauzov proposed to Christina Onassis via telephone in 1978. Knowing that the switchboard operators were listening in, she asked them if she should accept the proposal and they enthusiastically answered “yes!”.

On 1 September 1949, with the radiotelegraphic connection between Greece and America, the telephotographic service was launched in Greece. For the next four decades, all the images of political, social, sports, and cultural life that would be published in the press of that era would pass through ΟΤΕ’s telephotographic machine. With the improvement and spread of fax machines, telephotography gradually declined in the 1990s and eventually disappeared.

The technological innovation of transmitting images via telegraph was achieved in 1906 by the German physicist Arthur Korn. The telephotographic apparatus works as follows: The photograph is placed on the machine’s cylinder, which rotates and scans it in about 15 minutes. At the rear of the cylinder is a photocell which “reads the photograph”, by transferring small or large currents over large distances with the assistance of amplifiers. At the point of destination there is a similar machine with a “clear” negative that is placed on the corresponding cylinder. With the help of a photocell, the electric signal is converted into illuminated radiation that blackens the clear film according to the data being received. This negative film is developed in about 20 minutes using the known photographic procedure, and so the photograph is received at the place of destination.  

The transmission of photographs and texts from a distance, a widespread and commercialised method in Europe and America since the 1920s, became possible in Greece with the installation of the telephotographic apparatus at the Central Telegraph Office of Athens. It was also made possible due to the collaboration with Cable & Wireless, which permitted telephotographic connection (or wirephoto connection) with London and New York. It took 10 minutes to transmit a telephotograph from Athens to London, and the cost ranged between 145,000-199,500 drachmas, depending on the size of the photo. In 1957, when the contract between the government and Cable and Wireless ended, this service was turned over to OTE.

The service almost exclusively served news reporting photography needs and therefore its development was intrinsically linked to the world of the press. Technicians usually kept copies of telephotographs for back-up purposes, resulting in the accumulation of published and unpublished photographs which were kept in one of the telephotography rooms. These copies constitute the core of the OTE Group's Telecommunications Museum collection, which currently consists of about 13,500 photographs.

The year 1965 marks a significant milestone in the history of satellite communications, since Ιntelsat I (nicknamed Early Bird) was placed in geostationary orbit – the first of many satellites of the International Telecommunication Satellite Organisation. In the same year, Greece was represented by OTE at the signing of the participation contract with the International Satellite Organisation. Five years later, the first antenna was commissioned at the Centre of Satellite Communication in Thermopylae, which is one of the first in Europe.

At the start of the 21^st century there was a great need for the country to expand its satellite communication, primarily due to the television coverage of the 2004 Olympic Games and the increased demand for internet and mobile telephony services. Greece became a member of the European Space Agency (ESA) in 2001 and leased Kopernikous, the first Greek Satellite, the following year.

The first Greek Satellite (HELLAS-SAT), which was manufactured in France, was launched from Cape Canaveral in May 2003. The HELLAS-SAT project was costly and difficult; however, it was achieved with own means, since Greek and Cypriot technicians participated in the design. The satellite covered a large part of Europe, Africa, Asia and was a great commercial success for OTE.

“At the tone the time will be...”

The Speaking Clock was used by OTE from 1975 to 2000 for the time information service. This is a steel construction on which a precision clock and large rotating metal cylinder are mounted. Recorded on the cylinder are the spoken minutes, hours, and seconds of a twenty-four-hour day.  For 25 years, whoever called 141, would hear the time in Greece from this system. Since 2008, 14844 has transmitted the time using digital means.

Since the founding of OTE, recorded public information services were in place via the astylekti (spoken announcements system), a special machine that rebroadcast useful information. These services operated 24 hours a day, using special recordings that provided information on various issues, such as 115 for news, 111 for the racecourse, 148 for the weather, 102 for pharmacies etc.

The messages for these services were recorded on a rewritable metal disc. These recordings were made at either of the two studios on the 2^nd floor of the building at 85 Patission Street. These services started operating in 1950 and, through many conversions, continue to this day.

At this point, we present an installed complete analogue telecommunication system with two terminals and all intermediate equipment that was used to ensure communication. It constitutes part of the automated centres’ rack-mounted converters (urban and long distance) in Athens and Thessaloniki.

The invention of the telephone by Graham Bell in 1876 gave rise to the first manual telephone exchange. The call procedure involved lifting the receiver and turning the handle (crank) to signal the telephone exchange and the respective operator. The caller would tell the operator whom he wanted to talk to, either by stating their name or their telephone number, and the operator would then connect him with the other person.

The transition from manual to automated exchanges happened thanks to a chance event. Around 1880 in Kansas City, USA, Almon Brown Strowger (1839-1902), an undertaker, decided to install a telephone exchange in his office with the intention of increasing business. Among the operators that he hired was the wife of a competitor, and as a result, when a customer would call, she redirected calls to her husband's office. Thus, Strowger invented the rotary dial in 1889, effectively solving the automatic telephony problem. From then on, anyone who wanted to call a number could do so by dialling the number on their device without the need for operators.

The first automatic telephone exchange was established and operated in 1892. In Greece, analogue automatic telephone exchanges operated until the end of 1980, when network digitisation was introduced, and the network is 100% digitised today.

A typical telephone line layout from the OTE telephone exchanges to our home. When the telephone first made its appearance, two simple telephone devices were directly connected via copper cable. The rapid increase in users led to the need for telephone exchanges. It was not possible for the Exchanges to be directly connected with subscribers, given the large number of telephone lines. Thus “intermediate” distribution frames (cabinets) were locally created where the subscribers of an area were radially connected, thus reducing cable length to a minimum.

Up until 1980, the telephone line that started from the telephone exchange was connected to the cabinet via a copper cable and, in the same, the connection continued to our home. From 1980 onwards, the gradual digitisation of the network began, marking the switch from copper to optic fibre.

In the first phase, optic fibre cables replaced copper cables in the connection of urban exchanges to cabinets, permitting significantly faster Internet access speeds (from 24Mbps to 50Mbps). The next phase, which will lead to speeds of up to 1Gbps, sees the replacement of the copper cable that connects the cabinet with each home with optic fibre. Essentially, the entire route of the telephone line will consist of an optic fibre cable (Fibre to the Home).

The first mobile telephones/radio telephones were car phones. In 1973 the first call is made from a cellular phone by Martin Cooper. The device weighed 1.1 kilos.  In the 1980s, the first analogue mobile telephones were the size of a small suitcase.

The GSM, the Global System for Mobile Communications, was launched in 1992. In the same year, the first two mobile telephony company licences were issued in Greece, and in 1997 the first pre-paid mobile phones led to an increase in connections. In 1998 Cosmote entered the mobile telephony world by presenting the first 2G telephones, and the digital signal began.

2000-2010: With the mobile phone, every moment is redefined in direct connection with all daily activities. The mobile phone converts into a hybrid device: game console, entertainment device, camera.

2010-2020: The mobile phone is now a smart device. The third-generation mobile phones, 3G, arrived. Smart phones took over the market. A new era of unlimited multimedia possibilities began. The global adoption of 4G technology significantly improved video streaming and calls. Display size continues to increase for the best possible experience. At the same time, multiple cameras were added for better camera performance.

The first 5G service in Europe was launched in May 2019. It promises extremely high data speeds and reliability, ultra-high-definition video streaming and mobile gaming. The actual data transfer speeds will be 10 times faster than 4G.