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US3480742A
(en)
|
|
Hybrid circuit
|
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FI57503C
(fi)
|
|
Talstyrd kopplingsanordning
|
|
GB964335A
(en)
|
|
Improvements in or relating to telephone systems
|
|
US4776007A
(en)
|
|
Solid state trunk circuit
|
|
US3749857A
(en)
|
|
Cable testing device for long-distance cables, particularly for occupied cables
|
|
US4082924A
(en)
|
|
Reference signal circuit in a receiver for detecting two frequencies in a multifrequency tone signal
|
|
US2332643A
(en)
|
|
Telephone set circuit
|
|
SE7603136L
(sv)
|
|
Referenslikriktare i en mottagaranordning for detektering av tva tonfrekvenser i en tonsignal
|
|
US3300589A
(en)
|
|
Telephone ringing circuits
|
|
US3987375A
(en)
|
|
Transmission bridge exhibiting reduced distortion
|
|
SU374759A1
(ru)
|
|
Устройство индикации занятости абонентской телефонной линии
|
|
US2117843A
(en)
|
|
Frequency selective circuits
|
|
US1554007A
(en)
|
|
Antiside tone circuits
|
|
US1983477A
(en)
|
|
Telephone system
|
|
US3860878A
(en)
|
|
Temperature compensation circuit for a multi-frequency receiver
|
|
US1800962A
(en)
|
|
Electric circuit
|
|
US1724112A
(en)
|
|
Communicating system for power-transmission lines
|
|
US2923778A
(en)
|
|
Signalling device for double sideband carrier current telephone systems
|
|
GB397551A
(en)
|
|
Improvements in electrical impedance networks and amplifiers
|
|
SU482911A1
(ru)
|
|
Разделительное устройство
|
|
US1474408A
(en)
|
|
Detecting circuit
|
|
US1753325A
(en)
|
|
Retardation-coil system
|
|
US1416061A
(en)
|
|
Radioreceiving system having high selectivity
|
|
US1315584A
(en)
|
|
Selective receiving system for radiant energy |
|
US2238260A
(en)
|
|
Electric filter arrangement
|