Improvements in or relating to the Utilization of Hertzian and similar Radiations and Apparatus therefor.
Year: 1898

page_text: Date of Application, 9th Nov., 1898
Complete Specification Left, 9th Aug., 1899-Accepted, 9th Nov., 1899
Improvements in or relating to the Utilization of Hertzian and
similar Radiations and Apparatus therefor.
I, LOUIS HEATHCote Walter, of 53, Victoria Street, in the County of Middle-
sex, Electrical Engineer, do hereby declare the nature of this invention to be as
follows:
This invention relates to the utilization of Hertzian and similar radiations, its
object being to so effect the transmission and reception of such radiations that
they may be utilized without fear of the operation of the receiving apparatus by
the occurrence of unintentional or unauthorized radiations.
Obstacles to the utilization of these radiations have hitherto been met with
owing to the difficulty of preventing the reception at one station of false signals
from, or the undesired excitation of apparatus by, waves emanating from sources
other than the allied signalling or transmitting station.
According to this invention the radiations are emitted, preferably by automatic
apparatus, in accordance with a pre-arranged code and the receiving apparatus
is so devised as to be inoperative except when the radiations reach it in the codal
order, or at the codal intervals. In order to effect this, radiations are emitted
from the transmitting station with intervening periods of inactivity in conformity
with the pre-arranged code, and the receiving apparatus is, at such times as those
at which it should be in receipt of the codal impulses, put in connection, prefer-
ably by automatic apparatus, with an electric circuit through which currents,
controlled by the said impulses, are caused to pass. These currents may be
utilised to operate a relay or in any other desired manner.
Should impulses arrive at the receiving apparatus during the periods of codal
inactivity, these will fail to actuate the relay or other device since the receiver
will not during such periods be connected thereto.
It is further preferred, according to this invention, to put the receiving appar-
atus during the periods of codal inactivity in connection with another electric
circuit, so that the receipt of unauthorized impulses during such periods may be
detected or employed in any desired manner to indicate the absence or failure of
the true codal transmission.
One arrangement and construction of apparatus according to this invention
will now, by way of example, be described, the invention being, for the sake of
illustration, referred to as applied to the firing of submarine mines.
In this construction the transmitting apparatus is automatic and comprises a
wheel driven by a clock-work train, a spark coil, a Hertz oscillator and a releas-
ing mechanism for the wheel.
The wheel when released continues to rotate until it has completed one revolu-
tion when the locking mechanism comes into engagement and stops further
rotation. During that one revolution contacts disposed at predetermined intervals
around the periphery of the wheel, serve successively to momentarily complete
an electric circuit through a sparking coil connected to a Hertz oscillator. At

page_text: each completion of the circuit the oscillator sends off radiations and these radia-
tions are separated by intervals, of greater or less length, of inactivity deter-
mined by the position of the contacts on the periphery of the wheel. The operation
of the releasing mechanism, actuated preferably by a lever, may serve to momen-
tarily complete the circuit through the coil and to so cause a starting radiation
to be emitted and also at the same time may conveniently serve to wind the
driving mechanism for the wheel.
The receiving apparatus comprises a similar wheel on the periphery of which
are a number of contacts, whose relative positions correspond with those on the
transmitter wheel, the receiving wheel being timed to make one revolution in
approximately the same time as that occupied by one revolution of the trans-
mitter wheel. It is thus known which of the contacts on the receiving wheel will
be opposite a given fixed point when the circuit is being completed through the
contacts on the transmitter wheel, and at this fixed point is placed a suitable
rubbing contact capable of completing an electric circuit through those on the
revolving wheel or disc. The releasing or starting mechanism for this receiver
wheel is actuated by a relay in whose circuit is a coherer or other form of detector
for Hertzian radiations. The coherer is fitted with a decoherer in the usual
manner. The contacts on the receiving wheel which correspond to those on the
transmitter wheel, are placed in a local circuit containing a relay, the relay being
arranged to operate, say, by means of a pawl and ratchet, a firing device.
The first radiation sent off from the transmitter causes the coherer to close a
circuit through the receiver releasing relay which is therefore simultaneously
set in motion, and the subsequent radiations occurring at the intervals determined
by the code cause the coherer to close a circuit through the corresponding con-
tacts on the receiver wheel and so to impart the desired number of impulses
through the pawl and ratchet above mentioned to the firing device, which, having
received the desired number of impulses, closes the firing circuit and fires the
mine. Both the transmitting and receiving wheels having completed one revo-
lution, come to rest.
In order to prevent the firing of a mine by a number of radiations not occurring
at the true codal intervals, it is preferred to make a firing device consisting of a
ratchet wheel provided with two pawls and mounted on a spindle and provided
with a spring which tends always to rotate the spindle in one direction. The
relay, whose successive operations are to cause the firing, rotates the spindle
through one of these pawls against this action of the spring. The spindle is
held in position after each step by the other pawl. A further relay is provided
which when desired removes the pawls from the teeth of the ratchet wheel, and
so allows the spring to return the spindle to its starting position.
This releasing relay is placed in circuit with contacts on the receiver wheel
which are intermediate of the firing contacts so that should the coherer receive
a radiation when one of the codal contacts is not beneath the rubbing contact,
the last mentioned releasing relay is actuated and the firing device allowed to
return in the manner described. To fire the mine it now becomes necessary to
repeat the whole code of radiations with the correct intervening intervals.
In order to keep the driving mechanism for the receiver wheel properly wound
a step-by-step pawl mechanism may be conveniently employed actuated by a
relay automatically brought into circuit when the mechanism becomes sufficiently
run down and automatically thrown out when winding has been effected.
Where several mines are to be fired independently of one another from one
firing station, a number of transmitter wheels may be placed upon one spindle,
each provided with differently arranged contacts, so as to transmit radiations
each according to its own code, and each mine will be provided with a receiving
aparatus arranged to receive radiations according to the corresponding trans-
mitter wheels. According then as one or another of the transmitter wheels is
caused to operate the spark coil, so will one or another of the mines be fired.

page_text: This invention is not limited to the firing of submarine mines, this application
of the invention being merely given by way of example. Neither is it limited
to the precise details of construction hereinbefore described many variations in
the various mechanisms employed being obviously possible without departing from
the spirit of the invention. For example in place of the ratchet wheels described
for the firing device other cam mechanisms may be employed.
רד
Improvements in or relating to the Utilization of Hertzian and
similar Radiations and Apparatus therefor.
I, LOUIS HEATHCOTE WALTER, of 53, Victoria Street, in the County of Middle-
sex, Electrical Engineer, do hereby declare the nature of this invention and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement:-
This invention relates to the utilisation of Hertzian and similar radiations, its
object being to so effect the transmission and reception of such radiations that
they may be utilised without fear of the operation of the receiving apparatus by
the occurrence of unintentional or unauthorised radiations.
In cases where it is desired to actuate mechanism by means of these radiations,
obstacles have hitherto been met with owing to the fact that false signals i.e.
signals from other than the proper transmitting station are capable of operating
the mechanism controlled by the receiving apparatus.
According to this invention the radiations are emitted, preferably by automatic
aparatus, in accordance with a pre-arranged code and the receiving apparatus is
so devised as to be inoperative except when the radiations reach it in the codal
order, or at the codal intervals. In order to effect this, radiations are emitted
from the transmitting station with intervening periods of inactivity in con-
formity with the pre-arranged code, and the receiving apparatus comprises a
codal receiving device, so arranged that if the proper code signal is received a
local circuit is brought into operation, through a relay or other device and any
desired result-firing a submarine mine for example is brought about.
Should impulses arrive at the receiving apparatus during the periods of codal
inactivity or in non-conformity with the code, these will fail to actuate the relay
or other device, since the receiver will not, during such periods, be connected
thereto.
The relay preferably forms part of a "safety device" which is connected
during the periods of codal inactivity with another circuit from the receiver in
such a manner that the receipt of unauthorised impulses during such period may
be detected, or employed to indicate the absence or failure of the true codal trans-
mission. Conveniently, the false signals may cause the "safety device" to be
reset to its zero position; such resetting affords an indication of the receipt of
unauthorised impulses & is hereinafter described.
In the accompanying drawings which illustrate one construction of apparatus
for the utilisation of Hertzian radiations according to this invention.
Figure is a diagrammatic view showing the electrical connections of the
transmitting apparatus;
Figure 2 is a similar view of the receiving apparatus; shown partly in per-
spective for the sake of clearness;
Figures 3 and 4 are respectively a plan and elevation showing details of a por-
ion of the transmitting apparatus;

page_text: Figures 5 and 6 are similar view showing details of part of the receiving appar-
atus, and
Figures 7 and 8 are elevations at right angles to one another illustrating a
"safety device" which forms part of the receiving apparatus.
Like letters indicate like parts throughout the drawings.
A is an induction coil, to the primary winding A¹ of which is connected a
battery B and a magnetic make and break contact C, while an oscillator A³ is
joined in series with the secondary winding A³. These features form no part
of the present invention and are therefore not described in detail. The oscillator
and coherer are shown as being examples of suitable means for emitting and
receiving the radiations.
D is a codal transmitting device which may, for the present, be merely des-
cribed as comprising a disc D¹ supported on a shaft D2 and having a number of
projections 13 at intervals upon its periphery. The disc D tends to rotate in a
clockwise direction under the action of a spring (not shown), which may operate
through a train of wheels or other mechanism, and the spring is kept at an
approximately constant tension by causing the downward movement of a lever F
to wind it up through ratchet gear E. This lever F is pivotted about the shaft ])²
being free to turn on the latter and is controlled by the spring G. The disc 1)¹
is prevented from rotating by a catch H engaging with a corresponding notch
or recess D6 in another disc D, also carried upon the shaft D. The disc D'
is electrically connected through the shaft D2 to the winding C₁ of the make and
break contact C and thence to a battery B. The other pole of this battery is
joined to an electro-magnet H3 which acts upon the catch lever H. This pole of
the battery B is also connected to a spring contact D7 so placed that it is touched
by the projections D3 upon the disc D as the latter rotates.
A contact 1 upon
the lever is electrically connected to the shaft D2 and this contact F is brought
down upon another contact piece Fe connected with the electro-magnet H2 when
the lever F is depressed.
When it is desired to send a signal, the lever F is momentarily depressed on
to the contact F2. The effect of this is to complete the primary circuit of the
induction coil A-thus causing the oscillator A³ to spark-and also to release
the disc D, by the action of the electro-magnet H. The disc D¹ consequently
rotates, its spring having been wound up by the downward movement of the
lever F.
As the disc D¹ revolves, momentary contacts are made as each of the projec-
tions 13 passes the contact D', hence the induction coil A is caused to emit a
series of sparks at intervals corresponding to the distances between the projez
tions D³.
In the case illustrated in Figure 1, the periphery of the disc D¹ is divided up
into twelve equal parts, the projections 13 occurring at points corresponding to
parts 1, 5, 6, 8 and 11.'
The receiving apparatus (Figure 2) comprises a coherer K with tapper K¹,
battery B³ and electro-magnetic contact maker L, also a codal receiving device M
and safety device" N. When a ray or wave set up by a spark from the induc-
tion coil A actuates the coherer K, the contact maker L is operated by a current
from the battery B2 in the well-known manner.
The codal receiving device M comprises a disc M¹ carrying a series of con-
tacts arranged in an order corresponding to that of the projections upon
the transmitting disc D¹. These contacts are insulated from the disc M¹
but are
all connected together; a similar contact M3 which serves as
a starting contact is also carried by the disc M and is insulated there-
from and also insulated from the codal contacts M². The disc M is revolved by
a spring through any suitable train of wheels or other gear, and it is arranged
that its rotation shaft be approximately synchronous with that of the transmitter
disc D¹. As hereinafter described it is found convenient to keep the spring which
drives the disc H¹ wound to an approximately constant tension by an electro-

page_text: magnetic device, and as the spring which drives the transmitter disc D¹ is also
kept wound up within a small range, it follows that by suitably arranging the
gear and the strength of the springs synchronous rotation of the transmitting
and receiving discs is obtained. The disc M is prevented from rotating by a
catch M carried by a pivotted lever M, and in this case the catch, when in its
notch or recess M6, acts also as a contact piece. M7 is an electro-magnet, opera-
ting the catch lever M, and M8 is a spring, making contact with the edge of the
disc M or the contacts M2 M3 as they pass under it.
"
N is a safety device" which is operated from the codal receiver M, and, if
the latter receives the proper code signal, closes a local circuit and fires a mine,
or fulfils any other purpose for which it may be intended. If however, as will
presently be shown a wrong signal be received by the codal receiving apparatus,
the safety device does not complete the local circuit. N¹ and N are ratchet
wheels mounted upon the shaft N, the wheel N¹ being rotated tooth by footh
by means of a pivotted lever N* when the latter is actuated by an electro-mag-
net N against the action of a spring Ne. The lever N is provided with a pawl N
which engages with the teeth of the ratchet wheel N The rotation of the
wheel N takes place against the action of a spring N8 and the wheel is prevented
from flying back between the strokes of the lever N, by means of a pivotted
ratchet No which engages with the teeth of the wheel N. This ratchet N° is
controlled by a spring N10 and an electro-magnet N", the latter also acting when
energised to relase the pawl No. When the ratchet wheels N¹ and N2 are uncon-
trolled by their pawls or ratchets the spring N8 causes them to rotate in a clock-
wise direction until a pin N12 comes in contact with a stop N¹³. This action
ensures a definite zero position.
Upon the shaft N is mounted a contact arm N¼ which is always in contact
with a brush N15 and when it has been rotated through a definite angle-that is
to say, when the electro-magnet N has, through the lever N, rotated the wheel N¹
for an amount equivalent to a certain number of teeth--it also makes contact
with a spring N and thus completes a local circuit, part of which is indicated
at O. When the local circuit is intended to fire a mine, a safety plug should
always be provided as at 0¹, this plug not being inserted until the mine is laid.
In order that the disc M¹ may always rotate at substantially the same speed,
the spring which drives the train of wheels is kept approximately fully wound
by means of a winding device, such as indicated at P Figure 2. A lever P¹ is
attached to the winding pin P2 of the driving mechanism, which is so arranged
that rotation in a counter clockwise direction, that is, a downward movement of
the lever P will wind up the spring. The lever P¹ carries at its other extremity
a toothed rack 13 with ratchet teeth; and a pivotted lever P is provided with a
ratchet P which, when the lever P1 is pulled down by an electro-magnet 1",
engages with the teeth of the rack P³ and thus winds up the spring. The lever P4
is so arranged that normally, that is to say when the electro-magnet P is not
energised, the ratchet P5 is clear of the teeth upon the rack P³, so that the
lever is free to rise gradually as the spring of the winding device uncoils.
The upstroke of the lever P is caused by a spring P. Guides are provided at
Po to keep the rack P³ vertical, and a make and break contact is provided for the
lever P as at p.
The lever PI carries two contacts P and when it is in its highest position,
one of these contacts P" touches a stop P12; on the other hand when the lever P¹
is in its lowest position, contact is made between the lower contact P and
another stop P13. The stop P12 is connected to an electro-magnet P₁ and through
it to a battery B3, and the stop P¹³ is connected to another electro-magnet Pl³,
the winding of which is joined to a lever P and also to the battery B³. The other
pole of the battery B³ is connected to the contact pieces P. The lever P16 is.
pivotted at or near its centre and is controlled by a spring P17, so arranged that
when the lever is deflected one way or the other, the spring tends to keep it in its
deflected position. The electro-magnets P¹ and P¹³ each control one end of the

page_text: lever P16 and the end adjacent to the electro-magnet P4 is provided with a con-
tact P18 which, when the lever is drawn towards the electro-magnet P, touches
a stop P which is electrically connected to the lever P*.
If now the lever P¹ rises in consequence of the use of a receiver M, it will at
last make contact PI2. The electro-magnet P4 then pulls down the lever p
making contact at P and the current flows from the battery B through the
make and break contact p and electro-magnet 16, thus causing the lever P+ to
move up and down, and through the rack P³ to pull down the lever P¹, and wind
up the spring. This action continues after the contact at P12 is broken on account
of the action of the spring P17, it continues in fact until the lever P¹ descends to
its lowest position and makes contact at P13. When this occurs the electro
magnet P1 is energised and pulls the lever P over.
The operation of the codal receiving device M is as follows:-
When the first momentary contact is made by the transmitter lever F, as
previously described, the spark at the oscillator A³ sets up a wave or radiation
which is received by and actuates the coherer K in the usual manner. The electro-
magnet L is energised and attracts the lever L' making contact at L³; a current
then flows from the battery B³ through the contact spring Me, starting contact M³
and electro-magnet M7, thus releasing the disc M₁ which starts revolving in
synchronism with the transmitter disc D¹. Before the lever M is attracted by
the electro magnet M', a momentary current passes through the lever from the
wire marked a and thence through the catch M5, disc M¹ and wire b to the electro-
magnet N This momentary current releases the ratchet wheels N' and N2 and
allows the spring N8 to bring the "safety device" N back to its zero position,
if it should not already be in that position.
The contacts M2 being spaced to correspond with the projections D³ upon the
transmitter disc D¹ and the two discs starting together and rotating synchron-
ously, it follows that the coherer will be actuated by the true code signals when
contact pieces M2 are under the contact spring M8. When this occurs the current
passes from the contact spring M8 into the particular contact piece M2 and thence
by the wire c round the electro-magnet N Thus it will be seen that if the co-
herer is actuated as each contact piece M2 comes under the spring M8, the wheel N!
will be turned through as many teeth as there are contact pieces. In the case
illustrated for example, the wheel would be turned for an amount corresponding
to five teeth, there being five codal contact pieces. The contact maker N¼4 is so
arranged that when the "safety device" has been turned through this amount,
the local circuit O will be completed.
If now the coherer be actuated by a wave other than one of the true codal
waves, that is to say, by a wave occurring during one of the intervals between
the codal contacts, the contact spring MS will then be in connection with the
disc M' and the current will consequently flow from the contact piece M8 through
the disc M and the wire b to the electro-magnet N". This being energised re-
leases the wheels N¹ and N2 and the "safety device" automatically returns to
zero. After any such false signal it would of course be necessary to repeat the
true code signal before the local circuit could be completed.
It may be desired to operate local circuits at various places independently from
one transmitting apparatus, such a case, for example, would occur where several
mines are to be fired independently of one another from one firing station. To
accomplish this, a number of transmitter discs may be placed upon one spindle,
each provided with differently arranged contacts, so that each disc will transmit
radiations according to its own code. Each receiving station will be provided
with a codal receiving apparatus, arranged to receive signals according to the
code of its corresponding transmitter disc, and therefore as one or another of the
transmitter discs is caused to operate the induction coil, so will one or another
of the local circuits be closed.
If it be desired to have several local circuits close together each operated by its
own "safety device," the codal receiving device is provided with a number of

page_text: "
"
codal discs corresponding to the number of local circuits and each operated from
its own transmitter disc at the transmitting station.
Each receiving disc operates safety device and if the local circuits are all
worked to bring about a common result-say steering a boat-a relay or other
device is inserted in each local circuit so that when any one local circuit is closed
the operation of the other local circuits forming the same group is cancelled, so
that the particular circuit is free to produce the desired effect without hindrance.
For example the steering of a boat might be controlled by three receiver discs
each with its own "safety device," the local circuits serving to place the helm
a-port," a-starboard" and "amidships" respectively. The operation of the
"helm a-port" "safety device" will preferably not only close its own local cir-
cuit but will release the helm from the control of the local circuit called into
action by the previous order, leaving it free to move into the new position viz:
"a-port." The other "safety devices" act in a similar manner.
16
Figures 3, 4, 5, 6, 7 and 8 illustrate by way of example one construction of
practical apparatus on the lines indicated diagrammatically in Figures 1 and 2,
parts being omitted for the sake of clearness in all the figures.
Figures 3 and 4 show one form of codal transmitting device such as is repre-
sented in Figure 1. The shaft 12 is supported in bearings in a back plate Ds and
standard D, and carries the disc D and two codal discs D¹. The spring con-
tact I) is mounted upon an insulating block D in such manner that it may be
moved along a bar 1" and thus work in conjunction with either of the codal
discs . The catch lever H is pivotted to the standard D as at 112 and is pro-
vided with a counter-weight H. The current is led into the shaft 12 and disc D¹
by a brush ; and the whole transmitting apparatus is mounted upon a base-
plate D.
The codal receiving device illustrated in Figures 5 and 6 is constructed on very
similar lines to the transmitting apparatus described above. The shaft M carrying
the codal disc M' is supported in bearings in a back plate and standard M
The disc M comprises an ebonite back disc m carrying a brass disc m' upon its
face and the latter is recessed at intervals corresponding to the code signals,
the codal contacts M³ consisting of pins attached to the back disc m and situated
in the centre of the recesses in the disc m¹. Current is received by the codal con-
tacts from an insulated sleeve M2 to which they are all connected and a
brush M makes a rubbing connection with the sleeve M. A similar sleeve M¹4
and brush 5 serve to lead the current to the release contact M³, and third
brush M16 makes connection with the shaft MP and disc m¹.
The catch lever M is pivotted at M" to the standard M" being however insu-
lated from it: and the lever M and catch M are in electrical connection with the
spring contact M8. The catch M³ is only in electrical connection with the disc m¹
when it is in the recess Mº; after being withdrawn from the latter by the electro-
magnet M it rests against the outer edge of the back portion of the ebonite disc m,
being made broad enough for that purpose. The parts forming the codal receiv-
ing device are mounted upon a base M18 which may also conveniently support
the winding device P which is however, not illustrated in Figs. 5 and 6, all neces-
sary particulars being given in Figure 2.
Figures 7 and 8 show a convenient construction of the "safety device" N. This
corresponds in all essential details with the perspective sketch of the device in
Figure 2, the parts being supported by plates N fixed to a base N18. The lever N4
carrying the catch or ratchet N is jointed as at n, the portion bearing the catch N5
being acted upon by a spring n². This portion of the lever N is prolonged so
that it may be acted upon by the electro-magnet N, and thus the latter when
energised disengages both the ratchets N and N from their respective wheels.
In the drawings above described various parts have not been lettered or des-
cribed, but parts such as stops for regulating the amount of movement of the
various levers, terminals etc., need no description as their function is at once
evident to any one having a knowledge of the art.

page_text: If desired a testing device may be employed in connection with the receiving
apparatus and such a testing device may conveniently consist of a transmitting
apparatus similar to that at the transmitting station, but put into operation only
on the completion of the local circuit by the "safety device." This transmitter
may be made to acknowledge the receipt of a correct codal signal upon a receiv-
ing apparatus at the transmitting station.
It is to be clearly understood that this invention is not limited to the precise
details of construction herein before described, many variations in the various
mechanisms employed being obviously possible without departing from the spirit
of the invention, for instance, if desired electric motors may be used instead of
clockwork to drive the transmitter and receiver.
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. In apparatus for the utilisation of Hertzian and similar radiations the com-
bination with apparatus for receiving radiations in the form of a codal signal of
a "safety device" which completes a local circuit or otherwise operates to produce
the desired effect only when a true code signal is received.
2. In apparatus for the utilisation of Hertzian and similar radiations the com-
bination with apparatus for receiving radiations in the form of a codal signal of
a "safety device" which completes a local circuit or otherwise operates to produce
the desired effect when a true code signal is received and automatically returns to
its zero position if a false signal is given.
3. In apparatus for the utilisation of Hertzian and similar radiations the com-
bination substantially as and for the purpose described with an oscillator a co-
herer and synchronous transmitting and receiving devices which automatically
send and receive a predetermined codal signal of a safety device."
"
"
66
4. In apparatus for the utilisation of Hertzian and similar radiations a safety
device which completes a local circuit or otherwise operates to produce the
desired effect when a true codal signal is received and automatically returns to its
zero position if a false signal is given.
5. In the utilisation of Hertzian and similar radiations the employment of
synchronous transmitting and receiving devices which automatically send and
receive a pre-determined codal signal substantially as described.
6. In apparatus for the utilisation of Hertsian and similar radiations the com-
plete codal transmitting device substantially as described and illustrated in
Figures 1, 3 and 4 of the accompanying drawings.
7. In apparatus for the utilisation of Hertzian and similar radiations the com-
plete codal receiving device substantially as described and illustrated in Figures 2,
5 and 6 of the accompanying drawings.
.5
8. In apparatus for the utilisation of Hertzian and similar radiations the com-
plete safety device" substantially as described and illustrated in Figures 2, 7
and 8 of the accompanying drawings.
9. The complete apparatus for the utilization of Hertzian and similar radiations
substantially as described or illustrated in the accompanying drawings.
Dated this 8th day of August 1899.
LOUIS H. WALTER.
Boult & Wade,
Agents for the Applicant.