| 摘要 |
PROBLEM TO BE SOLVED: To enable smooth call-out even if the call-out is transferred in a configuration of a plurality of intercom master units being connected via a communication network.SOLUTION: An intercom slave unit 1 simultaneously transmits a call-out signal to a plurality of intercom master units 2, and executes bidirectional transmission of voice signals with a responding intercom master unit 2. The intercom slave unit 1 comprises a slave unit memory 15 for storing groups of simultaneous call-out destination intercom master units 2. The slave unit memory 15 has stored a normal call-out destination group to be called out at first and a transfer call-out destination group in the case of transfer setting. If any of the intercom master units in the normal call-out group was switched to the transfer setting, the slave unit CPU 16 switches the call-out destination from the normal call-out destination group to the transfer call-out destination group. |
