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E & M Communications Corporation Patents |
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Assignee: E & M Communications Corporation
Address: New York, NY
No. of patents: 1
Patents:
| Patent Number |
Title Of Patent |
Date Issued |
| 3940569 |
Programmable toll restrictor |
February 24, 1976 |
| A toll restrictor for use in determining whether attempts to complete a trunk call are unrestricted is responsive to at least a first successively dialed three digit code of the call from the trunk to provide a control signal in response to this code being a restricted code to prevent th |
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