Method for testing subscriber line of private automatic...

Details Method for testing subscriber line of private automatic... Method for testing subscriber line of private automatic...

2005-10-25

2005-10-25

Tran, Quoc (Department: 2643)

Telephonic communications

Diagnostic testing, malfunction indication, or electrical...

Of trunk or long line

C379S001010, C379S022020, C379S024000, C379S027030

Reexamination Certificate

active

06959069

ABSTRACT:
A method for testing a subscriber line of a PABX (Private Automatic Branch eXchange) using a DTMF (Dual-Tone Multi-Frequency) signal. The method includes the step of controlling a DTMF transmitter in response to a line test request from an exchange operator to transmit the DTMF signal to the subscriber line, the step of receiving a component of the transmitted DTMF signal reflected from the subscriber line due to impedance mismatching, and the step of determining from a strength of the received DTMF signal component whether the subscriber line is abnormal.

REFERENCES:
patent: 4139745 (1979-02-01), Ashdown et al.
patent: 4754472 (1988-06-01), Hing
patent: 5410585 (1995-04-01), Kawaharata
patent: 5465287 (1995-11-01), Egozi
patent: 5528661 (1996-06-01), Siu et al.
patent: 5557539 (1996-09-01), Fitch
patent: 5596623 (1997-01-01), Uchiba et al.
patent: 5818904 (1998-10-01), Dean
patent: 5875230 (1999-02-01), Ganley et al.
patent: 6157704 (2000-12-01), Ishioka
patent: 6263048 (2001-07-01), Nelson et al.
patent: 6373923 (2002-04-01), Williamson et al.
patent: 6707886 (2004-03-01), Erving et al.
patent: 6744853 (2004-06-01), Van Rooyen
patent: 6748050 (2004-06-01), Lazarus et al.
patent: 2002-61360 (2002-07-01), None

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