Improved Method of Transmission through Submarine Cables and Apparatus therefor.
Year: 1887

page_text: Date of Application, 25th May, 1887
Complete Left, 9th Feb., 1888
Complete Accepted, 9th Mar., 1888
Improved Method of Transmission through Submarine Cables and
Apparatus therefor.
I JOHN GOTT of No. 12 Richmond Street Weston-Super-Mare in the County of
Somerset Telegraph Engineer do hereby declare the nature of this invention to be as
follows:-
In order to improve the legibility of signals received through a cable and in con-
sequence obtain increased speed of transmission. I form each signal by two currents.
The first-current goes to form the signal and is here called the signal current. The
second one (of opposite polarity) intended to neutralize or partially neutralize the
charge left in the cable by the signal current is commonly called the "curb" current.
The signals may be sent by hand in the usual way by two keys or by an automatic
system where perforated paper band is used and the alphabet may be that known as
the Mirror or Syphon Recorder alphabet.
My invention consists of a self acting device by means of which the cable being
connected to the armature of a relay is held in electrical connection with a reversing
key for a definite interval after the signal current is sent during which interval a
current of opposite polarity is sent into the cable-after which the cable is automatically
connected to earth.
This action on the part of the above mentioned relay is accomplished by an
application of the principle of retarding the demagnetisation of an electro magnet by
a shunt on the latter, and also by the proximity or otherwise of the soft iron armature
to the poles of the electro magnet.
A proper adjustment can be effected so that the apparatus will adapt itself to a
cable of any length and to any speed of transmission.
This adjustment is made by varying the battery power used to work the electro
magnet by the force of the spring used to withdraw the armature by varying the
distance of the armature from the poles of the electro magnet and by varying the
resistance of the shunt on the electro magnet.
The duration of the magnetisation of the electro magnet relay after these adjustments
are effected depends in some measure on the time the electro magnet is excited by the

page_text: local battery which is manipulated by the sending key. So that if the signals are
sent slow the armature is retained in position a longer time than if the signals were
sent fast, and this beneficial action of the electro magnet makes the system self-
adjusting within a considerable range of speed of working.
The effect of the curb current can be varied also by using a battery for the said
curb current, either less or greater than that used for the signal current.
The accompanying diagram illustrates one of the methods I employ.
Fig. 1. is the Transmitting relay.
a. the lever of the armature is connected to the condensers and cable. b the back
contact is connected to earth. c is connected to the movable lever of the changing
relay Fig. 2. d is the horse shoe electro magnet provided with a shunt (adjustable).
e a retractile spring (adjustable).
Fig. 2. is a polarized relay differentially wound and so connected that the same pole
of the battery will throw over the tongue of the relay to either contact point
according as the current is directed by the key through one or other set of coils.
Fig. 3. is the ordinary key, the levers of which for convenience of illustration are
placed one above the other. Each of these levers is provided with an auxiliary
insulated contact f. f. intended to make contact with the springs g. g. when the keys
are depressed.
The batteries are connected as shown. Lis the local battery, and M the line
battery, the centre of which is connected to earth.
The action is as follows:-
If the right hand key (marked o) be depressed "the local battery closes the trans-
mitting relay Fig. 1 and throws over the tongue of the changing relay Fig. 2. so as
to connect the key to c and through it with the cable. (The tongue of relay Fig. 2.
will remain over until the other key is depressed). The cable is now in connection
with the zinc pole of the line battery, the copper pole being to earth. A zinc current
therefore flows to line so long as the key is held down. When the key is raised a
copper current flows to line from the back contact of the key so long as the armature
of the relay Fig. 1. is kept closed by the influence of the extra current in the shunted
electro magnet-after this is spent the armature falls back on b. and puts the cable to
earth. If now the other lever s be depressed the tongue of relay Fig. 2. is thrown
over to the other contact and the armature of the transmitting relay is attracted and
the copper pole of the battery is now connected to line and when the key is raised a
zinc current flows to Line during the same interval as in the case of the other key,
and this process goes on for every depression of either key.
It will be understood that the changing relay is only reversed when the keys are
reversed.
· Dotel this 10th
C

page_text: Improved Method of Transmission through Submarine Cables and
Apparatus therefor.
I JOHN GOTT of No. 12 Richmond Street Weston Super Mare in the County of
Somerset Telegraph Engineer do hereby declare the nature of this invention and in
what manner the same is to be performed, to be particularly described and ascertained
in and by the following statement :-
In order to improve the legibility of signals received through a cable and in
consequence obtain increased speed of transmission-I form each signal by two
currents. The first current goes to form the signal and is here called the Signal
current. The second one (of opposite polarity) intended to neutralize or partially
neutralize the charge left in the cable by the signal current is commonly called the
"Curb current."
The signals may be sent by hand in the usual way by two keys or by an automatic
system where perforated paper band is used and the alphabet may be that known as
the mirror or Syphon Recorder Alphabet.
My invention consists of a self acting device by means of which the cable being
connected to the armature of a relay is held in electrical connection with a reversing
key for a definite interval after the Signal current is sent during which interval a
current of opposite polarity is sent into the cable after which the cable is automatically
connected to earth.
This action on the part of the above mentioned relay is accomplished by an
application of the principle of retarding the demagnetisation of an electro magnet
by a shunt on the latter and also by the proximity or otherwise of the soft iron
armature to the poles of the electro magnet.
A proper adjustment can be effected so that the apparatus will adapt itself to a cable
of any length and to any speed of transmission.
This adjustment is made by varying the battery power used to work the electro
magnet, by the force of the spring used to withdraw the armature by varying the
distance of the armature from the poles of the electro magnet and by varying the
resistance of the shunt on the electro magnet.
The duration of the magnetisation of the electro magnet relay after these adjustments
are effected depends in some measure on the time the electro magnet is excited by the
local battery which is manipulated by the sending key. So that if the signals are sent
slow the armature is retained in position a longer time than if the signals were sent
fast and this beneficial action of the electro magnet makes the system self adjusting
within a considerable range of speed of working.
The effect of the curb current can be varied also by using a battery for the said
curb current either less or greater than that used for the signal current.

page_text: The drawings left with my provisional specification illustrate one of the methods
I employ.
Fig. 1. is the Transmitting relay. a the lever of the armature is connected to the
condensers and cable. b. the back contact is connected to earth. c is connected to
the movable lever of the changing relay Fig. 2. d is the horse shoe electro magnet
provided with a shunt (adjustable). e a retractile spring (adjustable).
Fig. 2. is a polarized relay differentially wound and so connected that the same
pole of the battery will throw over the tongue of the relay to either contact point
according as the current is directed by the key through one or other set of coils.
Fig. 3 is the ordinary key, the levers of which for convenience of illustration arc
placed one above the other. Each of these levers is provided with an auxiliary
insulated contact intended to make contact with the springs g g when the keys
are depressed.
The batteries are connected as shown. Lis the local battery and M the line battery
the centre of which is connected to earth.
The action is as follows:-
If the right hand key (marked o) be depressed the local battery closes the trans-
mitting relay Fig. 1 and throws over the tongue of the changing relay Fig. 2 so as
to connect the key to C and through it with the cable (The tongue of relay Fig. 2
will remain over until the other key is depressed). The cable is now in connection
with the zinc pole of the Line Battery-the copper pole being to earth. A zinc
current therefore flows to line so long as the key is held down. When the key is
raised a copper current flows to Line from the back contact of the key so long as the
armature of the relay Fig. 1 is kept closed by the influence of the extra current in
the shunted electro magnet-after this is spent the armature falls back on 6 and puts
the cable to earth. If now the other lever s be depressed the tongue of relay Fig. 2
is thrown over to the other contact and the armature of the transmitting relay is
attracted and the copper pole of the battery is now connected to line and when the
key is raised a zinc current flows to Line during the same interval as in the case of
the other key. And this process goes on for every depression of either key.
It will be understood that the changing relay is only reversed when the keys are
reversed.
Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed I declare that what
I claim is.
1. A self acting device by which currents of an opposite polarity are sent into a
Telegraph cable after the main signal current is sent and the signal current may be
of any duration.
This device automatically connects the cable to earth after the reverse current has
been sufficiently prolonged to neutralize or partially neutralize the main signal current
in the manner described.
2. The combination herein described of an electro magnet relay a polarized
differential relay and two hand keys so connected that the two relays are simul-
taneously actuated by the same pole of the local battery, whichever key is depressed
in order move effectually to accomplish the object aimed at, namely to send automatically
and with perfect regularity reverse currents after each signal current.
T
حيم
1
11
1000