Agree 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.


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& 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