Path: 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

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
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