Tandy 1400 LT User Manual page 23

Testing
Your
Modem
4)
Note
that the
00 command
returns
you
to
your
previous
state.
So
if
you
enter
ATO0<CR>
once you have
initiated
RDL,
the
command
will
NOT
exit
the
RDL
mode
when
re-
turning
on
line.
To
exit
RDL
and
return
on
line,
you
MUST
enter
AT01<CR>.
If
your
modem
has
echoed back
the
test
message
exactly as you
sent
it,
your
modem,
the
remote
modem,
the
local data terminal
equipment and
the
phone
lines
all
check
out.
If
there
is
a problem:
If
the
test
message does
not echo back
correctly, either your
mo-
dem,
the remote
modem,
the data equipment
or the
phone
lines
are
at fault.
If
you have
already
successfully
performed
the
local
analog loopback
test,
you
know
that
your
modem
and computer
are
communicating
properly.
If
there
is
a
remote
operator,
he
or
she
may
wish
to
perform
a local analog
loopback
test as well to
verify that the
remote
modem
and computer
are
communicating.
Assuming
that
both
the
local
and remote
modems
have
success-
fully
performed
local
analog loopback
test:
1)
Can
you hear your
modem
dialing?
2) If
the
modems
are connecting but
the
test
message
is
not
coming
through,
you
may
have
a
problem
with the
phone
lines.
Disconnect
and
try
again.
3-5