Re: Subscriber Line Measurement and SLAC Settings

From: CBFalconer (cbfalconer_at_yahoo.com)
Date: 04/21/04 

Date: Wed, 21 Apr 2004 20:57:02 GMT

Bond wrote:
>
> I am working on POTS line card with Quad ISLAC and ISLIC on it. I need
> to set the SLAC parameters based on the Subscriber Loop Length for
> which I use WinSlac software provided by Legerity for calculating the
> SLAC parameters.
>
> 1. Is there any guidelines ( country specific standards ) on how to go
> about it like how the parameters are to be set for Short Loop or Long
> Loop?.
>
> 2. For certain short loop length I am operating in constant current
> region and then in resistive feed. On what basis we should go about
> deciding the region till when to maintain constant current feed?.
> Right now if my loop resistance becomes more than 650 Ohms (an approx
> value) it operate in resistive feed. If anyone have worked on these
> guide me on this regard.
>
> 3. The Loop Resistance of a subscriber line is a combination of Cable
> resistance and Station resistance (i.e Phone Resistance ) . From POTS
> side we can only determine the Loop resistance as a whole, how to know
> that the station resistance is so much and the Cable resistance is so
> much?. How this is been done in real senario?.
>
> If you guys know any Books or standards which tells how to do Line
> measurements on POTS subscriber line can you refer it.

What's wrong with TelCo standards? In the days of ubiquitous AT&T
there were lots of them, and I'm sure they haven't disappeared.
There is nothing very complex about a line that supplies between
20 and 60 ma of loop current basically from a central battery and
resistor. 

-- 
"I'm a war president.  I make decisions here in the Oval Office
 in foreign policy matters with war on my mind." -         Bush.
"Churchill and Bush can both be considered wartime leaders, just
 as Secretariat and Mr Ed were both horses." -     James Rhodes.

Relevant Pages

  • Subscriber Line Measurement and SLAC Settings
    ... SLAC parameters. ... about it like how the parameters are to be set for Short Loop or Long ... The Loop Resistance of a subscriber line is a combination of Cable ...
    (comp.arch.embedded)
  • Re: Subscriber Line Measurement and SLAC Settings
    ... >> I am working on POTS line card with Quad ISLAC and ISLIC on it. ... >> SLAC parameters. ... >> about it like how the parameters are to be set for Short Loop or Long ... >> side we can only determine the Loop resistance as a whole, ...
    (comp.arch.embedded)
  • Re: Again on ADSL line
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  • Re: Hearing aids, Inductive loops question
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  • Re: Beginner question on resistance
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    (sci.electronics.basics)
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