In the beginning, the push-button telephone was not exactly a big success story. On November 15, 1976, the Deutsche Bundespost introduced the device to the public, and it was officially launched in early 1977. Although the phone was quite modern at the time, it did not make a big impression on customers, who hesitated to order the device. That's not surprising: With the exception of a black block of push buttons for dialing, the "Fernsprechtischapparat" – as it was called in German – the stationary phone did not have much else to offer in terms of innovation. Many customers still preferred to use to good old rotary dial telephone. However, in the early 1980s, the push-button device gradually became more popular – and that marked the beginning of a success story that continues to this day. Now the button telephone is celebrating its 40th anniversary.
Hardly any everyday device has changed as much as the telephone. The journey from manual switchboards and operators to rotary-dial phones and push-button devices has been remarkable. It all started with the telephone invented by Philipp Reis in 1861. That device represented a stroke of genius – even if it was only capable of transmitting voice communication in one direction. Alexander Graham Bell succeeded in developing dialog transmission some 15 years later in the USA – and that was the breakthrough for this new communication technology. The first telephones were funnel-shaped hand devices containing a loudspeaker and microphone – users held them to their ears when listening, and then in front of their mouths when speaking. This was not very convenient, to say the least.
In 1877 the first telephone conversation in Germany using a Bell telephone took place. Siemens & Halske also produced its first telephones that year. These milestones indicated that the telephone was here to stay. And since then telephone technology has improved dramatically: In the beginning, the quality of voice transmission was very poor, and each telephone call had to be manually switched by an operator. The first public telephone network in Germany was established in 1881. The invention of the Strowger switch in the USA paved the way for automatic call switching in 1889.
From rotary dials to push buttons
The rotary-dial telephone was patented in 1913. The device functions according to the pulse dialing principle: In this type of telephone technology a DC loop circuit is interrupted according to a defined digit coding system for each signal transmitted. This allows the exchange to identify the caller's telephone number. Such developments made telephoning easier and more convenient. The first desk devices were delivered in an elegant black finish and featured a large rotary dial. Calls were made by inserting an index finger in the dial openings for each digit and moving the dial clockwise in succession until the dial stopped – for today's users, this process would seem clumsy and time-consuming.
In the early 1960s multiple frequency dialing was developed and then became the typical technology used for analog telephony. The dialed numbers are transmitted as tones having defined frequencies, thus enabling the replacement of the rotary dial with push buttons. The large raised buttons in a square configuration are pushed down to create the characteristic signal tones heard in the analog line. These devices were initially gray and then delivered in various colors starting in 1972: The so-called "desk phone" was available in fern green, orange and marbled color shades – quite a change from past designs. The handset and base were joined with a flexible cord, and the entire device was connected to a wall socket using a wire cord. Telephone "mobility" was limited to the length of these cords.
Today the twelve-button block or "keypad" is still standard, but it has become more ergonomic and easier to use: The buttons often feature back lighting, and little effort is required when pushing them. Wireless devices have been available for fixed-line networks since the 1980s. The transition from analog to digital telephony led to more connections per line, in addition to faster data rates and much more convenience: Answering machines, electronic telephone directories and number lists, automatic redialing, hands-free devices, baby phones, alarm clocks, calendars, etc. – not to mention HD tone quality and more. And yet the old rotary dial has not disappeared completely. Per app the dial can be brought to the smartphone touch screen for those who want a nostalgic telephone experience.