Hi,

I have a router, an external stand alone Analog Fax and a PC external modem
all connected to a DSL line (Analog Fax and modem via microfilters).

Internet and the Analog Fax work as they should.

However, when sending a fax via the win03 fax server (PC external modem and
programmed to send only and not to receive), the fax turns back and enters
through the Analog Fax as if was coming from outside the office.

If I disconnect the Analog Fax, then the fax does go to the right addressee.

How can this be possible? How is the fax bouncing back on the same lines and
howto prevent it?

TIA


Mike

We've hit this in many of our client's offices. It's not so much that the
fax is turning back and coming in through the fax machine as much as it is
that the fax machine "hears" the fax tones on the line, thinks there is an
incoming fax, and starts receiving the fax. (If you listen to the modem's
speaker, in many cases you'll hear the fax tones [the series of "beeeeeep
pause beeeeeep pause beeeeeep" tones] begin as soon as the modem finishes
dialing, even though the phone call has not yet connected.) Many fax
machines don't bother checking that the phone actually rang -- they simply
hear the tones and start processing. Since the fax modem sees that it is
communicating with a fax machine, it dutifully starts sending (even though
the phone line may still be ringing through the modem's speaker). What you
end up with is usually a garbled fax.

You can _try_ installing a phone line isolator in front of the fax machine.
(Plug the line isolator into the phone jack on the wall, then plug the phone
line from the fax machine into the back of the line isolator.) The line
isolator will drop the phone line signal to the fax machine when it detects
that the line is in use and it wasn't the device behind the line isolator
that is using the line. The fax machine then won't hear the fax tones so it
will stay out of the way.

However, we've had mixed success with line isolators, to the point that we
now require clients to simply get a second, dedicated fax line instead. The
isolators seem to work fairly well on a standard analog POTS line, but
anything connecting through a PBX is flaky at best. But if you're
interested, I believe this is the line isolator that we used to use:
http://www.twacomm.com/Catalog/Model...ANLCHB31LX7N78

- Bill

Bill Bartlett
meridianEMR, Inc.
http://www.meridianemr.com/

"Mike" <(E-Mail Removed)> wrote in message
news:e2ds%(E-Mail Removed)...
> Hi,
>
> I have a router, an external stand alone Analog Fax and a PC external
> modem all connected to a DSL line (Analog Fax and modem via microfilters).
>
> Internet and the Analog Fax work as they should.
>
> However, when sending a fax via the win03 fax server (PC external modem
> and programmed to send only and not to receive), the fax turns back and
> enters through the Analog Fax as if was coming from outside the office.
>
> If I disconnect the Analog Fax, then the fax does go to the right
> addressee.
>
> How can this be possible? How is the fax bouncing back on the same lines
> and howto prevent it?
>
> TIA
>
>
> Mike
>
>

Try hanging the fax machine off the phone port of the modem. That way,
whenever the modem has the line, the fax will be isolated. The fax machine
can still be used for send and receive as long as you keep the fax server
doing send only.


"Mike" <(E-Mail Removed)> wrote in message
news:e2ds%(E-Mail Removed)...
> Hi,
>
> I have a router, an external stand alone Analog Fax and a PC external
> modem all connected to a DSL line (Analog Fax and modem via microfilters).
>
> Internet and the Analog Fax work as they should.
>
> However, when sending a fax via the win03 fax server (PC external modem
> and programmed to send only and not to receive), the fax turns back and
> enters through the Analog Fax as if was coming from outside the office.
>
> If I disconnect the Analog Fax, then the fax does go to the right
> addressee.
>
> How can this be possible? How is the fax bouncing back on the same lines
> and howto prevent it?
>
> TIA
>
>
> Mike
>
>