Key system protective apparatus
Number of patents in Portfolio can not be more than 2000
United States of America Patent
Stats
-
Mar 18, 1980
Grant Date -
N/A
app pub date -
Nov 29, 1978
filing date -
Nov 29, 1978
priority date (Note) -
Expired
status (Latency Note)
Importance
Abstract
A circuit for apparatus to be used with a key system line card for providing electrical isolation between the line circuit and the central office. The adapter responds to ring current from the central office to close a path to the line circuit to cause the line circuit to respond. The circuit provides two-way supervision responding to change of conditions either at the station or at the central office, and also provides a time delay to prevent the circuit from entering the hold condition improperly.
First Claim
Family
International Classification(s)
Cited Art Landscape
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