Could a telephone line damage a modem ?

Hi,

My parents live in the country probably about five or more mile from
their telephone exchange, This is approximate so don't quote me on
that..

In the last couple of years I have manged to provide them with my old
hand-me-down PC's.

Equipped with a modem they first went in around about two years ago.

My mother dials up the internet via the modem and surfs the web..have
used several different ISP's Wanadoo, BT etc etc

Now here's the interesting part...

They're currently on their eighth modem !

The first one lasted about two-three months and then just would no
longer access a dial tone. I think this was a PCi Rockwell based 56K
modem. I'd used it for about three years without any trouble.
I put its failure down to just one of those things and replaced it with
a PCi 56K USRobotics.

This lasted about two months before that too went the same way.
Apparently starting to drop the call at first, then would not dial any
longer just like the first.

I replaced it with an Intel PCi modem which itself lasted about
two/three months.

This pattern continued with our getting ever more suspicious.

Along the way the PC has changed three times and we have also changed
the extension cable three times.

The basic telco cable run is from the apex of the roof outside their
bungalow where it is delivered from the pole across the road.
It attaches to the stonework relatively close to the mains electrical
wires from the nearby eletrical lines again from poles.
It then travels down the wall about a meter or two fairly close to
these electrical wires before they part and go their different ways.
The telco line then enters the house and goes to the BT master socket.
The first telephone is plugged in here and an extension line then goes
off upstairs to the second telephone in my fathers office.

>>From here there is a triple splitter, the second phone running off the
first socket and a third phone line which runs down to the living room
from the second socket and from the third socket a line runs down to
the computer room where it is split between a fourth phone and the
modem in the computer.

We checked indoors and none of the internal wiring in the house runs
near any internal domestic power lines.

We've also disconnected discontinued use of the fourth phone in the
computer room two modems ago. So that didn't seem to help.

All in all it would seem that something is slowly damaging the modems
which after several months use renders them inoperable.

When I bring them back to my house to test them they won't work here
either.
You cant hear the relays click open/close when you first switch the PC
on, which you normally can hear when they used to work.
Once they have failed they are completely silent at switch on as if the
relay has frozen up.

Two of them that I gave over to them were working here at my house for
some condsiderable time before I gave them to them to use.

They expired in the same fashion in a matter of a couple of months.

My parents say that although they have experienced the odd storm,
nothing radical, the modems failures do not appear to coincide with
these events at all and my mother religiously unplugs everything during
stormy weather, in fact the PC is only plugged in when they use it.

I've been told that it is possible to get inductance from outside power
cables which could transfer itself onto the telco wires which could
then feed back into the modem and slowly damage the circuitry. Is this
possible ?

BT don't seem to want to know and flatly refute the suggestion that the
telco wires may be too close to the incoming electrical wires.
My parents don't see eye to eye with BT at the best of times, they have
had endless problems with the telephone line to the house over the last
thirty or so years. Mostly due to the telco run running through the
branches of may trees on the way to where my parents live, causing
havoc in wet weather.
That said BT moved the telegraph poles around five years ago so that
the wires no longer get caught in the braches !

How can I check the internal sockets to see if there are spurious
voltages present ? Obviously it is probably something releativly slight
or perhaps not always present ?

Have they got too many devices on the line ? all the phones are REN1.
They only have three telephones and the modem now.

The current modem is another new US Robotics 56K installed today and is
working fine, though it'll only be a matter of six or seven weeks
before it fails no doubt !

Any advice would be much appreciated, I know modems don't cost much but
its starting to get a bit silly.

thanks

Jim.

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