User Manual
5,666,408
5
FIG.
13
illustrates
the
pin
connection
in
another
embodi
ment
of
the
one-to-two
extension
cable
wherein
two
of
the
receptacles
each
has
only
two
pins
while
the
plug
has
four
pins.
The
one-to-two
extension
cable
of FIG. 13
is
similar
to
the
one-to-two
adapter
of
FIG.
11
except
that
the
connecting
body
10
in
the
one-to-two
adapter
is
replaced
by
a
telephone
cable
11 comprising
four
wires.
The
present
invention
is
disclosed
according
to
the
embodiments
shown
in
FIG.
1
to
FIG.
13.
It
is
obvious
to
those
skilled
in
the
art
that
many
modi?cations,
additions,
and
deletions
can
be
made
therein
without
departing
from
the
spirit
and
scope
of
the
invention
as
set
forth
in
the
appended
claims.
What
is
claimed
is:
1.
In
a
dual-line
telephone
system
using
connectors
each
comprising
4
pin
positions
arranged
in
a
row
for
seating
electrical
contacts
wherein
the
two
inner
pin
positions
are
used
for
connecting
line
1
while
the
two
outer
pin
positions
are
used
for
connecting
line
2,
an
adapter
comprising:
1O
15
a
?rst
plug
having
two
?rst
pins
positioned
to
match
the
20
two
outer
pin
positions
of a
4-pin
telephone
jack;
and
a
?rst
receptacle
having
two
?rst
pins
positioned
to
match
the
two
inner
pin
positions
of
a
4-pin
telephone
Plug;
wherein
the
?rst
pins
in
said
?rst
plug
are
separately
and
electrically
connected
to
the
?rst
pins
in
said
?rst
receptacle
so
as
to
connect
line
2
of
said
telephone
jack
to
line
1
of
said
telephone
plug.
2.
The
adapter
of
claim
1
further
comprising
a
cable
having
a
plurality
of
wires
to
provide
electrical
connections
from
said
?rst
plug
to said
?rst
receptacle.
3.
The
adapter
of
claim
1
wherein:
said
?rst
plug
further
comprises
two
second
pins
posi
tioned
to
match
the
two
inner
pin
positions
of
said
4-pin
telephone
jack;
said
?rst
receptacle
further
comprises
two
second
pins
positioned
to
match
the
two
outer
pin
positions
of
said
4-pin
telephone
plug;
and
the
second
pins
in said
?rst
plug
are separately
and
electrically
connected
to
the
second
pins
in
said ?rst
receptacle
so
as to
connect
line
1
of
said
telephone
jack
to
line
2
of
said
telephone
plug.
4.
The
adapter
of
claim
3
further
comprising
a
cable
having a
plurality
of
wires
to
provide
electrical
connections
?om
said
?rst
plug
to
said ?rst
receptacle.
5.
The
adapter
of
claim
1
wherein
said ?rst
plug
further
comprises
two
second
pins
positioned
to
match
the
inner
pin
positions
of
said
4-pin
telephone
jack;
said
adapter
further
comprising
a
second
receptacle
having
two
?rst
pins posi
tioned
to
match
the
inner
pin
positions
of
another
4-pin
telephone
jack;
wherein
the ?rst
pins
in
said
second
recep
tacle
are
separately
and
electrically
connected
to
the
two
second
pins
in
said
?rst'plug
so
as
to
connect
line
1 of
said
telephone
jack
to
line
1
of
said
another
telephone
plug.
6.
The
adapter
of
claim
5
further
comprising
a
cable
having a
plurality
of
wires
to
provide
electrical
connections
from
said
?rst
plug
to
said
?rst
receptacle
and
said
second
receptacle.
7.
The
adapter
of
claim
1
wherein
said
?rst
plug
further
having
two
second
pins
positioned
to
match
the
inner
pins
of
said
4-pin
telephone
jack;
said
adapter
further
comprising
a
second
receptacle
having
four pins
positioned
to
match
the
corresponding
pin
positions
of
another
4-pin
telephone
plug;
wherein
the
?rst
and
second
pins
in
said ?rst
plug
are
separately
and
electrically
connected
to the
corresponding
pins
in
said
second
receptacle
so
as to
connect
line
1
and
line
25
35
45
50
55
6
2
of
said
telephone
jack
to
the
respective
lines
of
said
another
telephone
plug.
8.
The
adapter
of
claim
7
further
comprising
a
cable
comprising
a
plurality
of
wires
to
provide
electrical
connec
tions
from
said
?rst
plug
to
said ?rst
and
second
receptacles.
9.
In
a
dual-line
telephone
system
using
connectors
each
having
4
pin
positions
arranged
in
a
row
for
seating
elec
trical
contacts
wherein
the
two
inner
pin
positions
are
used
for
connecting
line
1
while
the
two
outer
pin
positions
are
used
for
connecting
line
2,
a
coupler
comprising:
a
?rst
receptacle
having
two
?rst
pins
positioned
to
match
the
two
outer
pin
positions
of
a
?rst
4-pin
telephone
cable
plug;
and
a
second
receptacle
having
two
?rst
pins
positioned
to
match
the
two
inner
pin
positions‘of
a
second
4-pin
telephone
cable
plug;
wherein
the
?rst pins
in
said
?rst
receptacle
are
separately
and
electrically
connected
to
the
?rst
pins
in
said
second
receptacle
so
as
to
connect
line
2
of
said
?rst
cable
plug
to
line
1
of
said
second
cable
plug.
10.
The
coupler
of
claim
9
further
comprising
a
cable
having
a
plurality
of
wires
to
provide
electrical
connections
from
said
?rst
receptacle
to
said
second
receptacle.
11.
The
coupler
of
claim
9
wherein:
said
?rst
receptacle
further
comprises
two
second
pins
positioned
to
match
the
inner
pin
positions
of
said
?rst
4-pin
telephone
cable
plug;
and
said
second
receptacle
further
comprises
two
second
pins
positioned
to
match
the
two
outer
pin
positions
of
said
second
4—pin
telephone
cable plug;
wherein
the
second
pins
in
said ?rst
receptacle
are
sepa
rately
and
electrically
connected
to the
second
pins
in
said
second
receptacle
so
as to
connect
line
1
of
said
?rst
cable
plug
to
line
2
of
said
second
cable
plug.
12.
The
coupler
of
claim
11
further
comprising
a
cable
having
a
plurality
of
wires
to
provide
electrical
connections
from
said
?rst
receptacle
to
said
second
receptacle.
13.
The
coupler
of
claim
9
wherein
said
?rst
receptacle
further
comprises
two
second
pins
positioned
to
match
the
inner
pin
positions
of
said
?rst
4-pin
telephone
cable plug;
said
coupler
further
comprising
a
third
receptacle
having
two
?rst
pins
positioned
to
match
the
inner
pin
positions
of
a
third
4-pin
telephone
cable plug;
wherein
said
second
pins
in
said
?rst
receptacle
are
separately
and
electrically
con
nected
to
the
?rst
pins
in
said
third
receptacle
so
as to
connect
line
1
of
said ?rst
cable
plug
to
line
1
of
said
third
cable
plug.
14.
The
coupler
of
claim
13
further
comprising
a
cable
having
a
plurality
of
wires
to
provide
electrical
connections
from
said ?rst
receptacle
to said
second
and
third
recep
tacles.
15.
The
coupler
of
claim
9
wherein
said
?rst
receptacle
further
comprises
two
second
pins
positioned
to
match
the
inner
pin
positions
of
said
?rst
4-pin
telephone
cable
plug;
said
coupler
further
comprising
a
third
receptacle
having
four pins
positioned
to
match
the
corresponding
pin
posi
tions
of
a
third
4-pin
telephone
cable
plug;
wherein
the
?rst
and
second
pins
in
said
?rst
receptacle
are
separately
and
electrically
connected
to
the
corresponding
pins
of
said
third
receptacle
so
as
to
connect
line
1
and
line
2
of
said
?rst
cable
plug
to the
respective
lines
of
said
third
cable
plug.
16.
The
coupler
of
claim
15
further
comprising
a
cable
having
a
plurality
of
wires
to
provide
electrical
connections
from
said ?rst
receptacle
to said
second
and
third
recep
tacles.