Current sensing trigger for a telephone system
AssigneeGreat Lakes Communication Co. of Michigan
InventorAllen C. Horak
Life of this patent
Estimating the term…
Abstract
In a loop closure seizure step-by-step telephone system, a pulsing circuit is provided comprising a current sensing trigger having first and second semiconductor barrier elements disposed in a series circuit relationship for receiving dial pulses generated by a first subscriber telephone set. The dial pulses establish a current through the first and second semiconductor barrier elements and a circuit is provided for sensing a trigger voltage established between first and second semiconductor barrier elements. A circuit is also provided for amplifying this trigger voltage and operating a stepping switch to interconnect the first subscriber telephone set and a second subscriber telephone set pursuant to a number dialed on the first subscriber telephone set.
Claims40
A loop closure seizure step-by-step telephone system comprising:
- a first subscriber telephone set;
- a central switching station;
- means for interconnecting said first subscriber telephone set and said central switching station;
- a stepping switch for connecting said first subscriber telephone set to a second subscriber telephone set;
- means for generating dial pulses representative of a number being dialed on said first subscriber telephone set;
- first and second semiconductor barrier means disposed in a series circuit relationship for receiving said dial pulses, said dial pulses establishing current therethrough;
- means for sensing a trigger voltage between said first and second semiconductor barrier means when a current is established therethrough;
- and
- means for amplifying said trigger voltage and operating said stepping switch to connect said first subscriber telephone set and a second subscriber telephone set pursuant to a number dialed on said first subscriber telephone set.
A current sensing trigger and amplifier for sensing the dial pulses from a first subscriber in a step-by-step telephone system comprising:
- first and second semiconductor barrier means disposed in a series circuit relationship for receiving said dial pulses, said dial pulses establishing current therethrough;
- means for sensing a trigger voltage between said first and second semiconductor barrier means;
- and
- means for amplifying said trigger voltage and operating a stepping switch to connect said first subscriber to a second subscriber.
Dependencies are inferred from the claim text.