Article View: sci.electronics
Article #975Telephone Standards
From: Larry Jones
Date: Wed, 26 Jul 1989 12:43
Date: Wed, 26 Jul 1989 12:43
21 lines
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1389 bytes
What are the standards for on-hook and off-hook voltage? I just got a second line phone line installed and bought a two line phone. On the old line, all is well. On the new line, the in-use LED is always lit, even when the phone is on-hook. Some quick exploration with my meter shows the on-hook voltage of the old line is about 45V, which gradually drops to about 30V, implying that there's a fair amount of capacitance somewhere that's being discharged by the meter. The new line shows an on-hook voltage of about 25V which is rock steady. The phone's LEDs seem to switch somewhere between 30V and 35V, which seem awfully high to me. So, is the line within spec and the phone hosed, or vice versa? ---- Larry Jones UUCP: uunet!sdrc!scjones SDRC scjones@SDRC.UU.NET 2000 Eastman Dr. BIX: ltl Milford, OH 45150-2789 AT&T: (513) 576-2070 "You can't get a body like mine in a bottle -- unless you push REAL HARD." - Judy Tenuta / Dr. Pepper
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Path: arc1-ca.pugleaf.net!utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!cbmvax!uunet!sdrc!scjones From: scjones@sdrc.UUCP (Larry Jones) Newsgroups: sci.electronics Subject: Telephone Standards Message-ID: <767@sdrc.UUCP> Date: 26 Jul 89 12:43:50 GMT Distribution: usa Organization: Structural Dynamics Research Corp., Cincinnati Lines: 21