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Tim Wescott Tim Wescott is offline
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Default Telephone On-Hook Current

On 03/01/2011 09:09 AM, Jim Thompson wrote:
How much current can you draw from a phone line (on-hook condition)
without annoying Ma Bell?

...Jim Thompson


CFR 47, part 68.312.b.1.i (1993 version -- you can look up the latest
yourself):

"The DC resistance between tip and ring conductors, and between each of
the tip and ring conductors and earth ground, shall be greater than 5
megohms for all DC voltages up to and including 100 volts."

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

Do you need to implement control loops in software?
"Applied Control Theory for Embedded Systems" was written for you.
See details at http://www.wescottdesign.com/actfes/actfes.html