Re: Busy out POTS line

floyd@xxxxxxxxxx (Floyd L. Davidson) writes:

>>I don't remember the exact value but it's always best to throw a certain
>>resistance across the line.

>True. A 0 ohm resistor is that exact value! :-)
....
>Consider that to guarantee an offhook the resistance has to be
>something less that about 325 ohms (I can't remember the exact
>resistance, but it is in the 300-350 range). If there is 60 mA
>of current, that works out to 1 watt. That is enough to cause
>a fire. If for some reason there is 120 mA, it is 4.7 watts,
>which is enough to cause a fire a lot quicker!

But Floyd.. Suppose I have a hunt group with multiple lines. If I
short out oh 10 or 20; why I might end up burning the CO to the
ground from the MASSIVE overload......

And the goons running DHS would decide I was therefore a terrorist,
and send me to Gitmo.... RIGHT????

Your local loop resistance has several elements.

a) the resistance in your phone/resistor.
b) The resistance of the local loop.
c) The resistance of the relay coil on the line card.

Now c) may be "relay-equivalent" in a modern CO line card, but BFD.

In any case R_total will be a+b+c and even if a=0, then the total
is anything but. And if the loop disperse 4.7 watts over 2.85 miles
of local loop trunkage, what is the power density per foot?

And in ANY case, if some fool designed the line card to smoke because
of a shorted local loop; then he shall be sent back to the Lucas
works to figure out how to make computers leak oil. A line card
interface should survive anything short of near-field EMP and if it
does not, well, back to BORSCHT soup for lunch.

The zero ohms hysteria belongs with Craig's postcards and NYC
sewergators...
--
A host is a host from coast to coast.................wb8foz@xxxxxxx
& no one will talk to a host that's close........[v].(301) 56-LINUX
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433
.

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