The post-war years witnessed a massive growth in telephone subscriber numbers, which more than tripled between 1950 and 1970 (from 271,935 to 835,325). They reached the half-million mark by 1959, and a million in 1976.
The late 1950s also saw new services, including the 111 emergency service number in 1958, the Yellow Pages in 1959 (to supplement the telephone directory, which first appeared in 1909), and self-dialling for toll calls in 1976. Computerisation further extended services. From 1980 SPC (Stored Programme Controlled) exchanges allowed three-way conference calls, putting calls on hold, and the diversion of calls.
From 1982 new higher-capacity optical-fibre wiring, in concert with SPC exchanges, let the network carry and switch ‘packets’ of data. It provided an early version of electronic mail and resulted in a rapid downturn in the use of telegrams. From 1986 pagers were also in regular business use.
Facsimile (fax) machines
The facsimile machine was first patented in 1843. Fax machines were used for specialist purposes such as transmission of newspaper photographs from the 1930s, but use was not widespread until the 1980s. The prior existence of the telegraph and teleprinter systems meant there was little demand for faxing, and the first machines available were slow and expensive.
When the development of digital imaging made it possible to send images quickly, and the cost of equipment dropped, use of fax machines expanded. Fax use declined in the 1990s, replaced by email, as use of desktop computers and printers became standard.
International cable and satellite links
From the 1950s and 1960s, overseas calling was easier. International submarine cables using improved technology were laid, notably the COMPAC (Commonwealth Pacific) system linking commonwealth countries.
These jointly owned cables and subsequent satellite access limited national control. They involved often complex negotiations with other countries and the International Telecommunications Union on how to share cable space, or (for satellites) the radio spectrum.
In 1971 New Zealand’s first earth-based satellite station was opened at Warkworth. For the first time television newscasts could feature extensive overseas footage, and in turn, New Zealand sent footage – including of the 1974 Christchurch Commonwealth Games – overseas.
COMPAC was part-funded by New Zealand to meet surging demands for overseas telephone calls. Opened in 1962, it linked New Zealand with Australia and Fiji. It was extended to Canada in 1963, and South-East Asia (as SEACOM) in 1967.
First satellite links
The same decade saw the arrival of the first worldwide satellite links. These were in large part American-funded and overseen by the Washington-based International Telecommunications Satellite (INTELSAT) Organization. New Zealand joined INTELSAT in 1965, the same year satellite calls to the UK began.