AU418991B2
(en )
1969-02-13
Circuit arrangement for generating tone signals in telephone installations
AU2557867A
(en )
1969-02-13
Circuit arrangement for generating tone signals in telephone installations
CA752496A
(en )
1967-02-07
Telephone line circuit
CA774181A
(en )
1967-12-19
Telephone line circuit
AU415255B1
(en )
1971-07-21
Improvements in audio tone calling generators
CA791228A
(en )
1968-07-30
Telephone conference circuit
AU418989B2
(en )
1971-11-18
Improvements in telephone switchboards
CA765480A
(en )
1967-08-15
Telephone signaling circuit
AU424305B2
(en )
1972-05-16
Public telephone installations
CA770692A
(en )
1967-10-31
Telephone system substation circuits
CA754244A
(en )
1967-03-07
Electronic switching telephone system
CA754677A
(en )
1967-03-14
Electronic switching telephone system
AU413623B2
(en )
1968-10-10
Electronic switching telephone system
CA752000A
(en )
1967-01-31
Electronic switching telephone system
CA752498A
(en )
1967-02-07
Electronic switching telephone system
CA735571A
(en )
1966-05-31
Supervisory telephone circuit
CA748512A
(en )
1966-12-13
Tone sounder for a telephone substation
CA763518A
(en )
1967-07-18
Line circuit for key telephone system
AU409318B2
(en )
1971-01-06
Conference circuit arrangements in telephone switchboards
AU415271B2
(en )
1968-09-19
Circuit arrangement fora subscriber set with built-in amplifier for telephone installations
AU416082B2
(en )
1970-04-13
Circuit for generating impulses
CA771268A
(en )
1967-11-07
Automatic telephone circuit arrangements
CA762095A
(en )
1967-06-27
Digital signal generator
CA733678A
(en )
1966-05-03
Interrupter circuit for telephone systems
AU413553B2
(en )
1969-01-04
Anti-side tone circuit