How to redial a CO line from an extension telephone of a PBX

摘要

end. TECHNICAL FIELD [0002];The present invention relates to a method for redialing a CO line in an extension telephone of a private branch exchange.;I. Technical Problems to be Solved by the Invention:;In the case of an extension telephone connected to a private branch exchange in the past, when the first call fails during a CO call and the user desires to redial using the one-touch key, the redialing function is not normally provided.;All. Summary of the Invention:;A telephone number dialed by a user at a predetermined idle time interval is stored together with the idle time, and when a user's redialing request occurs, an extension telephone of the private branch exchange which redials the stored telephone number according to the idle time, Redial method.;la. An important use of the invention:;cellphone.