CH252653A
(en )
1948-01-15
Circuit arrangement in telecommunications systems.
CH267007A
(en )
1950-02-28
Telephone set.
CH226354A
(en )
1943-03-31
Arrangement in telephone systems.
CH210688A
(en )
1940-07-31
Device on telephone sets with microtelephones.
CH252927A
(en )
1948-01-31
Circuit arrangement for determining one of a plurality of lines in telecommunications systems with at least partial dialer operation.
CH231157A
(en )
1944-02-29
Circuit arrangement in telephone systems with connecting lines provided with several branch points.
CH231156A
(en )
1944-02-29
Circuit arrangement in telephone systems with connecting lines equipped with several branch points.
CH233692A
(en )
1944-08-15
Circuit arrangement in telecommunication systems, in particular telephone systems.
CH225671A
(en )
1943-02-15
Circuit arrangement in telephone systems, in particular private branch exchanges, with several centers.
CH231803A
(en )
1944-04-15
Circuit arrangement in telephone systems with preset mixed selectors.
CH234468A
(en )
1944-09-30
Circuit arrangement in telephone systems with dialer operation.
CH225673A
(en )
1943-02-15
Circuit arrangement for switching off branch points in telephone systems with connecting lines equipped with several branch points.
CH238420A
(en )
1945-07-15
Test circuitry in electrical telecommunications systems.
CH245547A
(en )
1946-11-15
Circuit arrangement in telephone systems with several exchanges.
CH234897A
(en )
1944-10-31
Circuit arrangement in telephone systems with several exchanges that can be switched in series.
CH226796A
(en )
1943-04-30
Circuit arrangement in telephone systems with dialer operation.
CH225935A
(en )
1943-02-28
Circuit arrangement in telephone systems with dialer operation.
CH228776A
(en )
1943-09-15
Circuit arrangement in telephone systems with main and sub-offices.
CH237099A
(en )
1945-03-31
Circuit arrangement in telephone systems with several exchanges that can be switched in series.
CH243484A
(en )
1946-07-15
Circuit arrangement in telephone systems with several exchanges in series.
CH237098A
(en )
1945-03-31
Circuit arrangement in telephone systems with several exchanges in series.
CH237889A
(en )
1945-05-31
Circuit arrangement in telephone systems with main and sub-offices.
CH226358A
(en )
1943-03-31
Circuit arrangement for telephone systems with main and sub-offices.
CH244782A
(en )
1946-09-30
Circuit arrangement for telephone systems with main and sub-offices.
CH225895A
(en )
1943-02-28
Intercom speaker system with conference operation.