MENTS IN TELEGRAPH SIGNALLING APPARATUS FOR INCREASING THE SPEED OF WORKING TELEGRAPH CABLES OR LONG HIGHLY INSULATED AERIAL LINES
Year: 1878

page_text: PROVISIONAL SPECIFICATION left by Frederick Trimmer at the Office of the
Commissioners of Patents on the 29th May 1878.
"IMPROVE-
FREDERICK TRIMMER, of 14, Waterloo Place, Pall Mall, London.
MENTS IN TELEGRAPH SIGNALLING APPARATUS FOR INCREASING THE SPEED OF
WORKING TELEGRAPH CABLES OR LONG HIGHLY INSULATED AERIAL LINES."
This Invention has for its object an improvement in the speed of working tele-
graph cables or long highly insulated aerial lines.
I combine with any ordinary key used in connection with the Morse or mirror
systems of working one or more electro-magnets with armatures, which are
actuated by a local battery or the working battery current (the former by pre-
ference). These electro-magnets are governed by and follow the movements of the
key, and their action is so regulated that at the proper moment of time during or
between the formation of each signal the current passing through the line to the
distant station is either reversed, weakened, cut off, or shunted away from the
circuit, as may be most advantageous, so as to leave the cable or line in as favour-
able a state as possible for the reception of the following current.
This apparatus can be used with advantage in connection with long aerial lines,
or submarine or underground cables of any length; it is also applicable to the
Morse, mirror, syphon, recorder, or any other system of working telegraph lines.
I use in connection with the arrangement a five pointed switch, a key of any
ordinary pattern commonly used in telegraph working provided with a few
additional contacts, but by preference a key specially arranged for the work. I
also use two resistance boxes, one containing about 500 units, the other about 50;
one or more polarized or unpolarized electro-magnets with one or more armatures
to each electro-magnet, the number being dependent on the description of curb
desired, and the method of working to which this arrangement is to be applied.
I use by preference a separate local battery of three or four cells to actuate the
electro-magnets, so as to make the system independent of the ordinary batteries
used for working.

page_text: The apparatus is constructed and arranged so that on the first pressure of the
key the full strength of the working battery passes to line for a greater or less
period.
The action of the armatures of the electro-magnets is regulated by means of
springs and an adjustable resistance, and they are connected in circuit in such a
manner that at the proper moment, that is, after the greater or less period above-
mentioned, contacts are made or broken, either successively or simultaneously
diverting to earth, or through a high resistance the working battery current, so as
to leave the line or cable in as favourable a state as possible for the reception of
the following current.
If preferred the working currents can be reversed or cut off after the greater or
less period instead of being weakened or shunted.
The manner in which these changes are effected is as follows:-When the key
is depressed before the ordinary working battery contact is made, a contact is made
which closes an independent local battery circuit through an electro-magnet, and
one or more armatures are set in motion. Immediately after closing this circuit
the working battery is applied to the line or cable at the key in the ordinary
manner. The one or more armatures thus influenced effect the changes already
described.
In double current Morse working, like contacts and changes are made and
effected with reference to the negative battery when the key is released, as have
herein been shown to take place with regard to the positive or marking current
when the key is depressed.
When the working currents are used to set the armatures in motion through the
medium of the electro-magnets no contacts are made by the key other than those
ordinarily used. This arrangement is obviously adaptable to any method of
translation.