Telephone numbers in Australia plan (including the "Trunk Access Code"), presented in domestic format. (Geographical region boundaries do not exactly follow State borders.) The current numbering plan would appear to be sufficient to cope with potential increase in demand for services for quite some time to come. The 06 and 09 area codes are completely unused. In addition, each current area code has large number "ranges" unallocated. When dialling from outside Australia, after dialling the appropriate International Access Code it is necessary to dial the Country Code for Australia (61) followed by the nine digit "National 'Significant' Number". (The + symbol is used to
Dialling (telephony) are decoded by the receiver to determine the keys pressed by the user. For example, the key "1" produces a superimposition of tones of 697 and 1209 hertz (Hz). Dialling (telephony) Dialling, (dialing in US English), is the action of initiating a telephone call by operating the rotary dial or the telephone keypad of a telephone. Prior to Strowgers invention of SXS, rotary switch in 1891, telephone connections involved cranking a handle to generate a voltage that operated a bell on the remote operator's board; the operator would then on the line to the subscriber and speak to them, they