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US2676209A
(en)
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|
Coin-controlled telephone system in which tariff rates for telephone calls are audibly transmitted automatically to a calling subscriber
|
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US1841084A
(en)
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Telephone system
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SE187861C1
(cg-RX-API-DMAC7.html)
|
|
|
|
US2278172A
(en)
|
|
Telephone system
|
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US2402700A
(en)
|
|
Telephone system
|
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US1530968A
(en)
|
|
Recording device
|
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US1726983A
(en)
|
|
Automatic telephone system
|
|
US1944269A
(en)
|
|
Telephone system
|
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US1394642A
(en)
|
|
Electric signaling system
|
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US2427000A
(en)
|
|
Coin-operated telephone system
|
|
US1660975A
(en)
|
|
Telephone system
|
|
US1916760A
(en)
|
|
Telephone exchange system
|
|
US2733295A
(en)
|
|
lomax |
|
US1804767A
(en)
|
|
Telephone system
|
|
US2623125A
(en)
|
|
Automatic party line metering
|
|
US1542649A
(en)
|
|
Multioffice telephone system
|
|
US1804766A
(en)
|
|
Telephone system
|
|
US1312702A
(en)
|
|
martin |
|
US1823679A
(en)
|
|
Call charging telephone exchange system
|
|
US1851185A
(en)
|
|
Telephone system
|
|
US1670303A
(en)
|
|
Automatic telephone system
|
|
US1648009A
(en)
|
|
Machine-switching selector-switch |
|
US2520962A
(en)
|
|
System for automatically ticketing telephone calls
|
|
US1567223A
(en)
|
|
Controlling system
|
|
US1354051A
(en)
|
|
Call-registering system
|