prov:value
| - H04M 11/00 [58] Field of Search340/l49, I80, 177 VA, 177 V2; 179/2 A, 2 R, S R; 324/62 R, 65 R, 115, Primary Examinerl(athleen H. Claffy Assistant Examiner-Tommy Pr Chin Attorney, Agent, or Firm-John E. Wagner [57] ABSTRACT Disclosed is a system for utilizing existing telephone subscriber lines during ON hook conditions for low level direct current signalling.
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