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Series pathfinding and setting via same conductor in tandem crosspoint switching netwrk
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(en)
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Code call circuit for paging in a pbx
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SU163650A1
(cg-RX-API-DMAC10.html)
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Ring trip and dial pulse detection circuit
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Line and link sensing technique for pabx telephone system
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GB550235A
(en)
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Improvements in telephone systems
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Telephone system
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GB683881A
(en)
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An automatic telephone or telegraph system
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Add-on conference trunk
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Level-hunting selector
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Multi-group primary-secondary-spread crossbar telephone system
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Line lockout in a cross point switching system
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Selector circuit
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Automatic telephone switching comprising electronic control equipments
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Selector switch circuit
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Crosspoint selector for reed relay matrix
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(en)
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Digit impulse scanning arrangement for a communication switching system
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P. a. b. x selector-connector switch
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(en)
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Automatic telephone systems
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GB496138A
(en)
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Improvements in or relating to telephone systems
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(en)
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Automatic telecommunication exchanges
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GB329366A
(en)
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Improvements in or relating to automatic or semi-automatic telephone systems
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(en)
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Automatic telephone system with improved line selecting apparatus
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(en)
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Terminal hunting system in an automatic telephone switchboard
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Selector switch metering circuit
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