The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 01, 1977
Filed:
Aug. 26, 1976
Barry Sheldon Bosik, Parsippany, NJ (US);
Dale Eugene Stone, Cedar Knolls, NJ (US);
Bell Telephone Laboratories, Incorporated, Murray Hill, NJ (US);
Abstract
A single channel carrier system for telephone service is disclosed including a remote terminal having a ringing generator included therein for generating ringing signals to operate the ringers of remote subscribers. The ringing generator is a dc-to-dc converter for stepping up a battery voltage to ringing voltage lvel that is interrupted at a 20 Hz rate. The generation of ringing signals is controlled by a carrier signal interrupted at a ringing rate. Detection of the ringing signals on the carrier utilizes a delay circuit to prevent response to inadvertent signals as well as delay hysteresis to ensure the bridging of detection from one 20 Hz cycle to the next. The ringing generator must also be regulated, both in current and in voltage, to prevent danger to personnel, damage to equipment, and excessive power consumption.