CH211572A
(en )
1940-09-30
Switch memories, in particular for telephone systems.
CH143855A
(en )
1930-11-30
Circuit arrangement for telephone systems, in particular remote offices.
CH133031A
(en )
1929-05-15
Circuit breaking devices, in particular for telephone systems.
CH153049A
(en )
1932-02-29
Circuit arrangement in telephone systems.
CH138456A
(en )
1930-02-28
Selector switch for telephone systems.
AT126865B
(en )
1932-02-25
Circuit arrangement for automatic telephone systems.
CH153048A
(en )
1932-02-29
Circuit arrangement in telephone systems.
IE10493L
(en )
1930-01-11
Telephone party-line systems.
ES115719A1
(en )
1929-12-16
Telephone transmission systems.
CH116918A
(en )
1926-10-01
Counters for telephone systems.
AT108963B
(en )
1928-02-25
Circuit arrangement for telephone systems in series connection.
ES113078A1
(en )
1929-10-16
Telegraphic systems.
CH145562A
(en )
1931-02-28
Coin operated telephone for telephone systems with dialer operation.
AT114004B
(en )
1929-08-26
Circuit arrangement for telephone systems with main and sub-exchanges.
AT134445B
(en )
1933-08-10
Circuit arrangement for telegraph systems with voter operation.
AT121382B
(en )
1931-02-25
Telephone exchange voters.
AT121482B
(en )
1931-02-25
Circuit arrangement for telephone systems.
CH145563A
(en )
1931-02-28
Selector for self-connecting telephone systems
AT131950B
(en )
1933-02-25
Circuit arrangement for telephone systems with several offices in series.
AT126871B
(en )
1932-02-25
Circuit arrangement for a connecting line provided with several branch points in telecommunication systems, in particular telephone systems.
ES114965A1
(en )
1929-11-01
Improvements in electrical systems.
DK45984C
(en )
1932-07-25
Circuit arrangement for fully or semi-automatic Telephone Systems.
DK46218C
(en )
1932-09-19
Circuit arrangement for fully or semi-automatic Telephone Systems.
AT115431B
(en )
1929-12-27
Circuit arrangement for telephone systems with intermediate amplifiers.
ES93788A1
(en )
1925-07-16
Improvements in automatic telephone systems in general.