nited States Patent Office. 17, 1903.
Original applicationfiledJuly 16,1900, Serial ho. Serial
Bo. 723,188, dated March. 64,522. be
ing imperative requirement most prac
tical applications such systems signal- 55
ing intelligence transmission that the sig
nals messages should exclusive pri
vate, highly desirable away with
the above limitations, especially view of
the fact which have observed that the in- 60
fluence powerful electrical disturbances
upon sensitive receivers extends even on
land distances many hundreds miles,
and consequent^’, accordance with theory,
still farther sea.)
To all whom concern:
Be known that Nikola Tesla, citi
zen the United States, residing the bor
ough Manhattan, the city, county, and
5 State New York, have invented certain
new and useful Improvements Methods of
Signaling, which the following speci
fication, reference being had the drawings
accompanying and forming part the
ro same. When the oscilla
tions are very high frequency, the num-
• her the effective harmonics may large
and the receiver consequently easily dis
turbed extraneous influences such an
50 extent that when very short waves, such as
those produced Hertzian spark apparatus,
are used little advantage this respect to
be derived from timing the circuits.of one kind class and arranged that the 80
operation the receiver dependent upon
their conjoint resultant action. overcome these draw- 65
backs and enable great number trans
mitting and receiving stations operated
selectively and exclusively and without any
danger the signals messages being dis
turbed, intercepted, interfered with any 70
way the object mj’ present invention. lilo model. 23,847.
SPECIFICATION" forming part Letters Patent No. The liability receiver
being affected disturbances emanating
from other sources, well that the sig
nals messages being received instru
ments for which they are not iutended, may, too
however, reduced not only increased
number the cooperative disturbances or
.
NIKOLA TESLA, NEW YORK, Y.
M . Dividedandthis applicationfiledJune 14,1901. Evidently circuit however well
constructed and adjusted respond exclu
sively to' vibrations one period apt to
be affected higher harmonies and still
45 more lower ones. scientific design the sending
and receiving circuits and other apparatus
and skilful adjustment the same these
objects may measure attained; but
in loDg experience have found that not-
30 withstanding all constructive advantages and
experimental resources this method in
many cases inadequate.
Broadly stated, this invention consists in
generating two more kinds classes of
disturbances impulses distinctive char
acter with respect their effect upon re- 75
ceiving-circuit and operating thereby dis
tant receiver which comprises two more
circuits, each which tuned respond
exclusively the disturbances impulses
. Thus while have
succeeded operating selectively under
certain favorable conditions more than one
35 hundred receivers most cases prac
ticable work successfully but few, the
number rapidly diminishing as, either owing
to great distance other causes, the energy
available the tuned circuits becomes
40 smaller and the receivers necessarily more
delicate. Gen
erally special device, highly sensitive, is
io connected the receiving-circuit, which in
order render still more susceptible and
to reduce the liability its being affected
by extraneous disturbances carefully ad
justed tune with the transmit-
25 ter.
In certain systems for transmitting intelli
gible messages governing the movements
and operations distant automata electrical
impulses disturbances produced suit-
15 able apparatus are conveyed through the nat
ural media receiving-circuit capable of
responding the impulses, and thereby ef
fecting the control other appliances.
By employing only two kinds disturb
ances series impulses instead one, as
has heretofore been done, operate re- 85
ceiver this kind have found that safety
against the disturbing influences other
sources increased such extent that I
believe this number amply sufficient in
most cases for rendering the exchange sig- 90
nals messages reliable and exclusive; but
in exceptional instances greater number
may used and degree safety against
mutual and extraneous interference attained,
such comparable that afforded 95
combination-lock
