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On 6/20/06 6:04 PM, in article , "Pooh Bear"
wrote:

Don Bowey wrote:

On 6/20/06 1:48 AM, in article net, "jasen"
wrote:

On 2006-06-19, Pooh Bear wrote:

Franc Zabkar wrote:

On 19 Jun 2006 08:44:34 -0700, put finger to
keyboard and composed:

Looked at several Motorola SM56 modems an all have the same fault-non
infinite resistance at line jack which causes them to take over the
line once the line is plugged, so none of the telephones can be used!
Checked the MOV and it is ok and there is no relay on modem !(at least
not a box type, just few too many smd transistors doing smth?)

There is a diode bridge so the line interface is a 'dry transformer'
type.

If there is a transformer, then the DAA is probably dry, as you say.
Otherwise there would usually be two chips, one on the line side and
one on the host side, with two or three ceramic caps providing the
isolation.

The one I have has no relay or transformer.

I'm seeing 19M across the line on the bare pcb.

At 48V ?

Bye.
Jasen

I'm late getting into this, but.....

Have you looked at the documentation for the modem? As a condition of the
Registration program in the U.S., the manufacturer must declare the Ringer
Equivalence for the modem. There are two ways to determine the Ringer
Equivalence Number (REN), and one of them is the Tip to Ring dc resistance.
If they declare REN=2 then the 19M you see may be normal, and is probably
not your problem.

The box contains a driver CD, a leaflet like 'manual' with none of that info,
a
piece of foam plastic and the pcb in an anti-static bag.

The pcb has TUV, CE and FCC ( but not an FCC id ) printed on it together with
what I originally took to be the BABT approvals symbol ( but possibly isn't ).

I suspect the above are bogus.

There's no manufacturers info anywhere but I recall that it was sold as
'Mentor'
brand.

I've an idea to report this. Maybe I'll give the company that sold it a chance
to replace it though ?

Graham

Even a soft-modem needs hardware. For example, my new HP computer has a
soft-modem and it works through a PCI card, and it is called a PCI
soft-modem. Among other things, it has the RJ11 physical connection to the
phone line. It is this PCI card that will have the REN and other FCC
required info.

I imagine some motherboards could have this functionality so that a PCI card
isn't needed, but whether it's a PCI card, or it's on the computer
motherboard, it must contain all FCC Part 68 and Part 15 info, or it won't
be in compliance with Federal Law.

If it will help, tomorrow I will pull the PCI card and see what info it
provides.

What are you using for a terminal program?

Don