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BE419410A
(enrdf_load_stackoverflow)
|
|
|
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US2052051A
(en)
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|
Telephone system
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US2135921A
(en)
|
|
Automatic telephone system
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US1727137A
(en)
|
|
Automatic telephone system
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US1855779A
(en)
|
|
Telephone system
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US2886641A
(en)
|
|
Recorded message service for telephone paystations
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US3749846A
(en)
|
|
Ring trip circuit
|
|
US3796836A
(en)
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Device for automatically signalling incoming calls on normal already engaged telephones
|
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US1292827A
(en)
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Telephone-exchange trunking system.
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SU7072A1
(ru)
|
|
Телефонное устройство
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|
US1515362A
(en)
|
|
Automatic telephone system
|
|
US1222077A
(en)
|
|
Fraud-detecting telephone toll system.
|
|
US1383677A
(en)
|
|
Telephone-exchange system
|
|
US1543886A
(en)
|
|
Telephone system
|
|
US4169221A
(en)
|
|
Method and apparatus for testing a subscriber line group marker of a telephone central office cross bar switching device
|
|
SU427486A1
(ru)
|
|
АБОНЕНТСКИЙ КОМПЛЕКТНА ТРАНСФЛЮКСОРАХ ДЛЯ АВТОМАТИЧЕСКИХТЕЛЕФОННЫХ СТАНЦИЙ С ЭЛЕКТРОИНЫГу\УПРАВЛЕНИЕМ
|
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US2806087A
(en)
|
|
Stopping circuit for selector switch
|
|
US3066194A
(en)
|
|
Alarm signal means
|
|
US1722538A
(en)
|
|
Automatic telephone system
|
|
BE336765A
(enrdf_load_stackoverflow)
|
|
|
|
US2862061A
(en)
|
|
Telephone line lockout arrangement
|
|
US1504267A
(en)
|
|
Machine-switching telephone system
|
|
US1742930A
(en)
|
|
Telephone system
|
|
US1504337A
(en)
|
|
Telephone system
|
|
BE353777A
(enrdf_load_stackoverflow)
|
|
|