Year: 1886

page_text: Date of Application, 30th July, 1886.
Complete Left, 2nd May, 1887.
Complete Accepted, 14th June, 1887.
We, DANIEL BOYD, of Lymm, in the County of Chester, Merchant, and SAMUEL
WILLIAMS, of Newport in the County of Monmouth, Secretary to the Newport
Monmouthshire Chamber of Commerce, Incorporated, do hereby declare the nature of
this invention to be as follows:-
Our invention relates to telephonic apparatus, and comprises a simple tension regu-
lator which serves as a transmitter. It also comprises an improved manner of coupling
up or connecting one or more induction coils with our improved transmitter.
In telephonic transmitters, as hitherto constructed, a diaphragm, tympan, sound-
board or equivalent device is used for conducting or communicating the sound-waves
or voice_vibrations to a microphone or tension regulator. In the specification of
Letters Patent granted to T. A. Edison and dated 30th July 1877 No. 2909 as
amended by disclaimer and memorandum of alteration filed 17th August 1882, what
is specifically claimed is not a tension regulator by itself, nor a diaphragm or
tympan by itself, but a combination of these two parts, any claim to one or other of
the said parts separately being specifically repudiated.
According to our invention we dispense in the transmitter with a diaphragm,
tympan, mouthpiece, soundboard, or similar device which separates the air on one side
of it from the air on its other side, and thus allows the differences of air pressure to
exist on its opposite sides which render it susceptible of vibration when the air-waves
come in contact with it; and which device gathers and takes up these sounds and
vibrates in accordance with and transmits them to a tension regulator. And we
employ a microphone or tension regulator so constructed and arranged that the air-
waves or voice vibrations may be caused to impinge directly upon the same and will
produce the required variations of resistance at the contacts of the said microphone
or tension-regulator. Our transmitter is constructed as hereinafter described, that is
to say, two lengths or pieces of wire either straight or curved are attached to any
suitable support and extend therefrom either parallel or at any desired angle to each
other. To the free ends or terminals of these wires are attached small sockets, bars,
or other pieces of carbon. The space between the said sockets is bridged over by

page_text: means of a rod or pencil or other piece of carbon resting in or upon the said sockets
or bars in loose contact therewith. The arrangement of these parts which we prefer
is the following viz:-The two wires are arranged vertically parallel to each other and
are bent or curved at their ends between and from which a pencil of carbon is
suspended. The pencil of carbon in this position is sufficiently sensitive to be acted
upon directly by the voice without the medium of any diaphragm, tympan, or similar
device upon which the voice would first impinge and which would impart the vibra-
tions thus received to the tension regulator before the said tension regulator had itself
received direct the pulsations of the air occasioned by the voice and had operated in
accord therewith.
We have proved by repeated experiments that a diaphragm, tympan or similar
device is not essential to the electrical transmission of speech.
A simple form of our transmitter is made by extending two thin wires parallel with
each other between the floor and ceiling of a room and inserting a pencil of carbon
in the middle to complete the circuit. This transmitter acts very well as a microphone
or tension regulator without any diaphragm other than that afforded by the ceiling or
the floor.
The construction of our transmitter may be varied without departing from the
nature of our invention.
Any suitable receiver may be employed in connection with our transmitter; for
example, one similar to that described in the English Mechanic of 11th August 1876
page 551, and consisting of a membrane such as gold-beater's skin having a small
iron armature attached thereto, and arranged in combination with an electro-magnet
excited by a battery. The form of instrument we prefer is identical with the apparatus
described in the specification of Letters Patent dated 9th December A.D. 1876
No. 4765 and disclaimed in the disclaimer and memorandum of alteration dated
18th February A.D. 1878.
We use the membrane receiver and our form of transmitter either with a direct
battery current on the line, or with both coupled up with the battery all in the main
or primary circuit of an induction coil, the line wire being in circuit with the
secondary of the said induction coil. The former mode is useful for local exchange
work and short lines, and the latter for long distance telephony.
In coupling up or connecting our transmitter with a receiver and induction coil, we
connect the secondary of the said induction coil, with the line-wire and insert one or
more batteries in the said line-wire, and we couple up or connect the receiver with
the primary of the said induction coil. The ends of the primary are connected with
the line and respectively to the poles of the said battery. In some instances, we divide
the primary circuit, and insert the receiver in one branch and the transmitter in the
other branch thereof.
In other instances, we couple up a transmitter in the primary circuit of one induc-
tion coil and a receiver in the primary circuit of another induction coil, instead of
using one induction coil for them both. In other instances, the induction coil is wound
with double or treble wires forming as many separate or independent primary circuits,
in one of which the transmitter is inserted, and in the other or others the receiver or
receivers.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicants.

page_text: Improvements in Telephonic Apparatus.
We, DANIEL BOYD, of Lymm, in the County of Chester, Merchant, and SAMUEL
WILLIAMS, of Newport, in the County of Monmouth, Secretary to the Newport
Monmouthshire Chamber of Commerce, Incorporated, 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:-
Our invention relates to telephonic apparatus and comprises various improvements
hereinafter set forth.
The main object of our said invention is to provide a telephone-transmitter with a
tension-regulator whereby the required variations or fluctuations of resistance in the
circuit may be produced without the use of a diaphragm, tympan, speaking-tube or
other resonant body for gathering up the sound-waves or voice-vibrations and trans-
mitting or imparting them to the tension-regulator.
In our improved telephone-transmitter, the tension-regulator consists of two or
more pieces of carbon or other suitable material suspended or supported in loose
contact so that the required variations or fluctuations of the current will he produced
by speaking upon, or in proximity to the said pieces, the sound-waves or voice-
vibrations impinging directly upon the same without the intervention of a diaphragm,
speaking-tube or similar device.
Another object of our said invention is to provide for facilitating the transmission
of sounds over long distances, and obviating or diminishing the ill effects of induction
from neighbouring wires. We accomplish this object by coupling up or connecting
our transmitter with a receiver, and one or more induction coils and batteries in the
novel and peculiar manner hereinafter described.
In the accompanying drawings, we have shown how our said invention may be
conveniently and advantageously carried into practice.
Figure 1 is a front view of one form of our improved transmitter.
Figure 2 is a side view of another form or modification thereof.
Figure 3 is a front elevation of a telephonic apparatus provided with one of our
improved transmitters.
Figures 4, 5 and 6 are diagrams illustrating our improved method or manner of
coupling up or connecting the instruments in the circuit.
Like letters indicate corresponding parts throughout the drawing.
Referring to Figure 1, A, B are two wires or thin metal rods which are fixed in a
stand or support C, which may be of any suitable description. D, E are blocks or
pieces of carbon or other suitable material which are attached in any suitable manner
to the upper ends of the rods or wires A, B. F is a carbon rod or pencil which rests
loosely in sockets in the pieces D, E, thus forming a tension-regulator which
resembles the well-known form of the Hughes microphone, but is distinguished
therefrom by the absence of any base or sound-board or equivalent acoustic device or
adjunct.
We find that, by reason of the loose contact between the blocks or pieces of carbon,
this tension-regulator is sufficiently sensitive to produce the required variations of

page_text: resistance when acted upon directly by the air waves or pulsations without the
intervention of any diaphragm, tympan, speaking-tube, mouth-piece or resonant case
or similar contrivance such as is generally used in telephone-transmitters heretofore
constructed.
The rods or wires A, B can be extended to any convenient length without impairing
the general efficiency of our transmitter.
In the modification of our transmitter shown in Figure 2, a block or piece D' of
carbon or other suitable material is attached in any suitable manner to the top of the
rod or wire A, and the rod or wire B is bent or curved at its upper end as shown,
and has inserted therein an adjusting screw G from which a piece E¹ of carbon or
other suitable material is suspended by means of a wire B₁, so that it is in loose
contact with the piece D¹. This contact may be varied by turning the screw G in
one or the other direction, as will be readily understood.
The rod or wires A, B are to be included in an electric circuit in the manner
hereinafter described or in any well-known manner.
We prefer to use, with our improved transmitter, a "membrane" or "gold-beater's
skin" receiver, constructed and operating substantially as described in the specification
of Letters Patent granted to W. Morgan Brown and dated 9th December A.D. 1876,
No. 4765, and referred to by the said W. Morgan Brown in his Disclaimer filed
13th February A.D. 1878. Any other well-known or suitable receiver may, however,
be used if desired.
In some instances, we employ a membrane receiver arranged in a case or box with
a single acoustic tube attached thereto.
In Figure 3, we have shown a telephonic apparatus wherein the tension-regulator
consists of blocks or pieces D, E of carbon attached to the wires A and B, and a rod
or pencil F of carbon resting loosely at its ends in sockets in the said blocks. ff, are
the telephone-receivers which, when not in use, are held in brackets C₁ pivotted to the
stand or support C, so that, when the said receivers are removed. therefrom, the
necessary connections will be made in a well-known manner.
In the diagrams Figures 4 and 5, a is an induction coil or transformer, b is the
primary circuit of the said induction coil. c is the line-wire or main-circuit, in which
is included the secondary of the said induction coil. d is a battery which is arranged
in the said main circuit. e is the transmitter, and f the receiver.
It will be seen that, in Figure 4, the primary b is connected with the line-wire con
each side of the battery d, and that the transmitter and receiver are both included in
the said primary circuit.
The current from the battery d takes the path of least resistance, as indicated by
the arrows, viz;-through the primary of the induction coil and through the
instruments e, f This current of low E.M.F. becomes, in the secondary, one of
high E.M.F. which traverses the line wire or, main circuit.
The induction coil, when engaged in receiving, acts as a condenser, the effect being
greatly augmented by the fact of a local battery current (no matter in what direction)
flowing in its primary. The connection at each end is the same, although repeated
experiment proves that it is quite immaterial how the poles of the battery are presented
to the line, that is to say, whether opposing poles, viz ;-two Z's in opposition or Z
and C to the line in regular sequence.
We sometimes divide the primary circuit as shown in Figure 5, and insert the
transmitter in one branch and the receiver in another branch thereof. The advantage
of this arrangement is that we can employ more battery power and consequently get
better results than has heretofore been practicable with this class of apparatus, without
using too much current through the carbon of the transmitter.
Moreover, in some instances, we couple up a transmitter in the primary circuit of
one induction coil and a receiver in the primary circuit of another induction coil,
instead of using one induction coil for them both, the other connections remaining as
above described.
In some instances, we use more than one battery.
According to another modification of our method of using an induction coil, the

page_text: said coil may be wound with double or treble wires forming as many separate or
independent primary circuits, in one of which we insert the transmitter and in the
other or others, the receiver or receivers, the necessary connections in each case being
made with a battery.
Figure 6 of the drawing shews one plan of carrying this out. b, 61, 63 are three
separate primary circuits, ff are receivers coupled up in b, 63; and e is the trans-
mitter coupled up in the circuit b¹. g, g, are the terminals of the secondary, going
direct to line and earth (or return) respectively, as shewn at h; or the line wire or
main circuit can pass through one or other or both of the batteries coupled up with
the receivers, without interfering with the general effect, as shewn by dotted lines at j.
That is to say, the portion of the line going to earth (or return) can pass through the
battery k in the manner shown by the dotted lines, and the other portion of the line
in the same way through the battery l.
Although we prefer to connect up the transmitter and receiver in the manner above
described, it is obvious that they may be otherwise arranged if desired.
For short distances, we sometimes omit the induction coil and connect the
instruments and the battery directly to the line-wire.
Having now particularly described and ascertained the nature of our said invention
and in what manner the same is to be performed, we wish it understood that
we claim ;-
First. A telephone-transmitter wherein the tension-regulator consists of pieces of
carbon or other suitable material suspended or supported in loose contact by means
of metal rods or wires substantially as herein-before described, to be acted upon by
the sound-waves or voice-vibrations without the intervention of a diaphragm, tympan,
speaking-tube, sound-board or the like.
Second. The improved telephone-transmitter constructed substantially as described
with reference to Figure 1 or Figure 2 of the accompanying drawings and operating
as above specified.
Third. The peculiar method or manner of coupling up or connecting the trans-
mitter and receiver or receivers, the primary circuit or circuits of one or more
induction coils, a battery or batteries and the line-wire or main circuit, substantially
as, and for the purposes, set forth.
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