Improvements in Simultaneous Telephony and Telegraphy.
Year: 1896

page_text: Date of Application, 17th Feb., 1896
Complete Specification Left, 13th Nov., 1896-Accepted, 17th Feb., 1897
PROVISIONAL SPECIFICATION.
Improvements in Simultaneous Telephony and Telegraphy.
We, EDWARD WYTHE SMITH of No. 66 College Street, Chelsea, London,
in the County of Middlesex Electrical Engineer, and THE NEW PHONOPORE
TELEPHONE COMPANY LD. of Faraday House, Charing Cross Road, London, W.C.
do hereby declare the nature of this invention to be as follows:-
Our invention relates to an improved system of telephones to work simul-
taneously on the same line wire with telegraphic or other electric signalling
apparatus.
For this purpose we employ a combination as follows:
For transmitting speech we make use of a microphone transmitter with an
induction coil as usually employed. The secondary of the induction coil is
connected at one terminal to "line" and at the other to "earth" (or "return
line"), a condenser being placed in either or both branches. Or the secondary
may be wound double as a phonopore, one wire being connected to line, and the
other to earth or return. The telephone receivers are interposed in one of the
branches of the secondary.
For calling attention we employ a magneto-inductor and polarized bell or ringer,
such as are ordinarily employed. We place these in series in the line, or as a
shunt to the telegraph apparatus. The telegraph apparatus does not work the
telephone bell, as the latter is polarized the armature will simply remain on one
side, and only be actuated by the alternating currents generated when the magneto-
inductor is worked.
At points where the line wires go to earth we employ an instrument with a
transformer wound with similar coils, one of which we connect in the circuit of onu
line wire, and the other in the circuit of the second line wire. By this means the
currents generated by the magneto-inductor, or the microphone transmitter, in
one line, induce currents in the second, and thus establish through telephonic
communication.
We also arrange a commutator to cut this transformer out of circuit, when
through communication is not required.
Dated this Fifteenth day of February 1896
COMPLETE SPECIFICATION
Improvements in Simultaneous Telephony and Telegraphy.
We, EDWARD WYTHE SMITH of 66 College Street Chelsea, London, in the
County of Middlesex, Electrical Engineer, and THE NEW PHONOPORE TELE-
PHONE COMPANY, LIMITED of 85 Queen Victoria Street, London, E.C.
formerly of Faraday House, Charing Cross Road, London W.C. do hereby
declare the nature of this invention and in what manner the same is to he
Improvements in Simultaneous Telephony and Telegraphy.
We, EDWARD WYTHE SMITH of 66 College Street Chelsea, London, in the
County of Middlesex, Electrical Engineer, and THE NEW PHONOPORE TELE-
PHONE COMPANY, LIMITED of 85 Queen Victoria Street, London, E.C.
formerly of Faraday House, Charing Cross Road, London W.C. do hereby
declare the nature of this invention and in what manner the same is to he
I Pone thi

page_text: performed, to be particularly described and ascertained in and by the following
statement:-
Our invention relates to an improved system of telephones to work simul-
taneously on the same line wire with telegraphic or other electric signalling
apparatus.
For this purpose we employ a combination as follows:-
For transmitting speech we make use of a microphone transmitter with an
induction coil as usually employed. The secondary of the induction coil is
connected at one terminal to fine and the other to earth or return line, a condenser
being placed in either or both branches. Or the secondary may be wound double
as a phonopore one wire being connected to line, and the other to earth or
return. The telephone receivers are interposed in one of the branches of the
secondary.
"
For calling attention we employ a magneto inductor and polarized bell or ringer,
such as are ordinarely employed. We place these in series in the line or as a
shunt to the telegraph apparatus. The telegraph apparatus does not work the
telephone bell, as the latter is polarized the armature will simply remain on one
side, and only be actuated by the alternating currents generated when the magneto-
inductor is worked.
Referring to the drawing in Fig. 1, M is the microphone transmitter connected
up through the battery CZ, the hook lever H to the terminals p, p' of the
"phonopore" induction coil A. 8, 1, 2, represent the secondary winding, one
branch of which is connected by the terminal 's' to the terminal L, and the other
by to the terminal E through the telephone receiver R.
MI is a magneto-inductor and B a polarized bell or ringer of the usual type.
Mis connected to the terminal L' and through B to the terminal L.
When this telephone is used at a station terminal to the line wire, the terminal L
is connected to line, and the terminal L' to the telegraph apparatus, terminal E
being connected to earth.
At an intermediate point we cut the line wire and connect the ends to the
terminals L, L'.
At points where the line wires go to earth we employ an instrument with
a transformer wound with similar windings, one of which we connect in the circuit
of one line wire, and the other in the circuit of the second line wire, and by this
means the currents generated by the magneto-inductor, or the microphone
transmitter, in one line, induce currents in the second, and thus establish through
telephonic communication.
We also arrange a commutator to cut this transformer out of circuit, when
through communication is not required.
In Fig. 2 the terminals L and L are connected to one line wire, and the
terminals and to the second line wire. That is the line wires are cut,
the two ends of the wires going to the distant stations are connected to the
terminals Land 7, and the two ends going through the telegraph instruments to
earth are connected to the terminals L' and . The terminal E is connected to
earth, similar to as explained in connection with Fig. 1.
Trepresents diagrammatically the transformer, the two windings being 1. 2
and 3. 4
The line circuits in the telephone are completed from the terminal L through
the key K, the polarized bell B and the transformer winding 2.1 to the
terminal L', and from the terminal I, through the key K', the bell B' and the
transformer winding 4. 3 to the terminal .
. The commutator G is connected so that, when the bar a is in the position
indicated, the winding 1. 2 is short circuited by the metal piece v.
through the
springs 5. 6, and the winding 3. 4 is short circuited by the metal piece w through
the springs 7. 8. The metal pieces & w are insulated the one from the
other.

page_text: The magneto-inductor MI is at one terminal connected to earth, and at the
other terminal to contacts c, of the keys K, K', so that, when either of these
keys is depressed, and the magneto actuated, currents are generated in the
corresponding line wire giving the call signal at the further station.
Call signals coming into this instrument from the line pass through the key, the
bell and the corresponding winding of the transformer.
The primary circuit of the "phonopore" coil A is completed as in Fig. 1.
The secondary at s is connected through the receiver R to the earth terminal E,
and at s through the switch S by the contacts a or b to the terminal L or
according to in which direction communication is desired.
When the transformer is in action, the bar a of the commutator G being at right
angles to the position shewn, currents from the line enter at the terminal L pass
through the key K, bell B and the winding 2. 1 of the transformer to the
terminal L inducing currents in the other circuit 1, K', B', 4. 3 and giving
through communication from one line wire to the other.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is :-
1. In simultaneous telephony and telegraphy the combination of a magneto-
inductor and polarized bell or ringer, for calling attention to the telephone, with a
"phonopore "induction coil, for transmitting speech, substantially as and for the
purpose described.
2. In simultaneous telephony and telegraphy the combination of a magneto-
inductor and polarized bell or ringer with a phonopore" induction coil and
transformer, for giving through communication from one line wire to another,
substantially as and for the purpose described.
Dated this Thirteenth day of November 1896 (ninety-six)
E. WYTHE SMITH.
THE NEW PHONOPORE TELEPHONE Co., LD.,
CHARLES ISAAC, Secretary.