AT109639B
(en )
1928-05-10
Impulse transmitter for subscriber stations in automatic telephone exchanges.
CH149577A
(en )
1931-09-15
Subscriber set for fully automatic telephone systems.
AT109597B
(en )
1928-05-10
Line selector for automatic telephone exchanges.
AT98365B
(en )
1924-11-10
Call counters for telephone subscriber stations.
AT109102B
(en )
1928-03-26
Self-hooking telephone exchanges voters.
AT105745B
(en )
1927-02-25
Automatic telephone switchboard.
ES80959A1
(en )
1922-06-01
Improvements in communication network installations for telephone exchanges.
ES80756A1
(en )
1922-05-16
Improvements in automatic and semi-automatic intercom devices for telephone exchanges.
AT113265B
(en )
1929-05-25
Circuit arrangement for fully automatic telephone exchanges.
CH120657A
(en )
1927-08-01
Self-collecting telephone station.
DK35348C
(en )
1925-12-07
Impulse receiver for automatic telephone exchanges.
CH126054A
(en )
1928-06-01
Telephone transmission line.
GR1378B
(en )
1926-12-31
IMPROVEMENTS IN SEMI-AUTOMATIC TELEPHONE SYSTEMS.
ES97051A1
(en )
1926-04-16
Improvements in automatic telephone systems.
AT109595B
(en )
1928-05-10
Telephone call transmitter.
AT121483B
(en )
1931-02-25
Device for selective calling of stations on a common line, in particular for telephone or telegraph exchanges.
AT116522B
(en )
1930-02-25
Circuit arrangement for long-distance traffic in telephone exchanges.
AT136580B
(en )
1934-02-26
Talk time counter for telephone desk stations.
DK46085C
(en )
1932-08-22
Circuit device for automatic telephone subscriber stations.
ES99048A1
(en )
1926-11-01
Improvements in automatic telephone systems.
AT112310B
(en )
1929-02-25
Circuit arrangement for call seekers in automatic telephone exchanges.
DK45254C
(en )
1932-02-15
Coupling device for automatic telephone exchanges.
DK35614C
(en )
1926-02-15
Automatic Dialer for Telephone exchanges.
CA253323A
(en )
1925-09-01
Party line automatic telephone system
AT118954B
(en )
1930-09-10
Telephone dialer.