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From: David Nebenzahl on 18 Jul 2010 02:20
On 7/17/2010 4:20 PM PlainBill47(a)yahoo.com spake thus:

> If you are going to ask for advice that you don't intend to use, the
> honorable thing to do is to tell us up front that this is purely for
> informational purposes. At a mimimum, afterwards say "Thanks, the
> problem has been solved." That at least give your helpers the
> satisfaction of having spent their time in a useful matter.
>
> This "I'm not going to do anything about it" is BULLSHIT!!!

I'm sorry you were offended.

No, I take that back: I'm actually *happy* that you were offended.


--
The fashion in killing has an insouciant, flirty style this spring,
with the flaunting of well-defined muscle, wrapped in flags.

- Comment from an article on Antiwar.com (http://antiwar.com)
From: David Lesher on 9 Aug 2010 19:41


Agree re: corroded wiring connection as likely cause.

Go to each jack and put a *milliammeter* across Tip-Ring.
Start at the demark.

You should see 20+ mA. If you don't, it's the wiring or jack.

As a next step, put the meter in series with a phone, and see if the off-hook
current is still >20mA.

The first indicts the upstream wiring; the 2nd is likely the phone.


--
A host is a host from coast to coast.................wb8foz(a)nrk.com
& 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
From: Bill Janssen on 10 Aug 2010 11:43
David Lesher wrote:
> Agree re: corroded wiring connection as likely cause.
>
> Go to each jack and put a *milliammeter* across Tip-Ring.
> Start at the demark.
>
The milliampmeter should be in series with a 400 Ohm resister. The
resister represents the resistance
in the phone.

Bill K7NOM
> You should see 20+ mA. If you don't, it's the wiring or jack.
>
> As a next step, put the meter in series with a phone, and see if the off-hook
> current is still >20mA.
>
> The first indicts the upstream wiring; the 2nd is likely the phone.
>
>
>
From: David Lesher on 11 Aug 2010 22:39
Bill Janssen <billj(a)ieee.org> writes:

>> Agree re: corroded wiring connection as likely cause.
>>
>> Go to each jack and put a *milliammeter* across Tip-Ring.
>> Start at the demark.
>>
>The milliampmeter should be in series with a 400 Ohm
>resister. The resister represents the resistance in the phone.

Not needed at all, and misses the point. The phone is not a
fixed resistance; it's a small voltage drop that varies with
loop length.

The outside plant loop and the line relay at the CO limit the
current. Let's say you are 5000 ft from the CO; that's 250 ohms
right there. The line relay is say 500 ohms. Worst case, 60 odd
mA. In reality the line card will limit it to far less.

Nothing you can do to your end of the loop will damage anything.

Your goal is to see the max available current. If it's not
sufficient at a jack, but is at the demark; there must be a bad
splice in the IW. And measuring the voltage with a open circuit is
sorta pointless.

--
A host is a host from coast to coast.................wb8foz(a)nrk.com
& 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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