Apparatus and method for on-demand activation of telephone line telemetry devices
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Apparatus and method for operating a telephone line telemetry device in a multiple host environment
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Multiplex system for automatic meter reading
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A telephone facility installation. (Machine-translation by Google Translate, not legally binding)
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An apparatus to perceive and convert in signals an indication of the consumption of a service apparatus. (Machine-translation by Google Translate, not legally binding)
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A signaling system for use in combination with a subscriber telephone appliance. (Machine-translation by Google Translate, not legally binding)
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Alarm and utility meter reading system employing telephone lines
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Alarm and utility meter reading system employing telephone lines
