Evening star., 1922-10-08
BY COMMANDER STANFORD C..
HOOPER,
United stSates Navy. Head Of the
radio division in the bureau OF en-
gineering. Navy Department.

ontsd stsates Navy. Head Of the
radio division in the bureau OF en-.
gineering. Navy Department.
Copyright. 1922. All rights reserved)
1t seems fantastic that the equiva-
lent of typewriter, associated with
no visible energizing medium, should
suddenly begin to function and con-
tinue functioning for several hours
at a stretch. and apparently of its
own volition.
Yet this phenomenon nows occurs at
the naval aircraft radio laboratory
at Anacostia. D. c., without exciting
other than passing interest.
Surely the ouija board of question
able memory had nothing on this
Unlike the ouija board, this contrap-
ton speaks coherently, utilizing the
English alphabet to form intelligent
words, phrases and complete SEN
tences. Moreover, it prints its prod
uct on paper without hesitation or
equiVocation and leaves it as a
permanent record
What appears fantastic today may
be reality tomorrow-and this is
especially true of radio. Five years
ago 1t would not have been consid-
ered possible to actuate typewriter
at distance solely by radio.
Yet this has now been done, and
the actuatinE agency was located in
Navy seaplsne in fight up to fifty
miles away while the recording, or
printing, agency was located on the
ground
Thus it has been demonstrated that
messages transmitted from aircraft
IN flight can be automatically printed
on paper on the ground. wholly by
radio o-mechanical means and without
the aid of any intervening medium
other than the ether and without the
aid of human hands.
Ihe transmitting agency is also
actua.,u by radio-mechanical means.
although human hands are required
to operate it.
Features OF the Teletype.
This device. which comprises a
transmitter and receiver. or printer. is
called teletype.
1t is familiar instrument in many
OF our large land wire commercial
telegraph offices, -naving been devel-
oped for land wire telegraphy 1t
daily transmits and receives many
! thousands of words of traffic over
| big cities.
| The principal features of the teIe-
! type consist of a keyboard. resem-
! bllng an ordinary typewriter key
i board; a small electric motor. and a
| printer. The keyboard levers are
arranged to control the lateral move
ment of a set of five selector bars
! within the keyboard base. The Sc
! lector bars are so notched that par
! ticular bars out of the five will slide
/ endwise upon the depression OF a par
ticular key and control the position of
| certain locking latches and contact le-
; vers mounted upon the base.
The eictric motor drives shaft
FOR rotating transmitter cam shaft
operating the cams against those
contacts which have been selected by
| the depression of particular key.
. The operation is such that the con-
! tacis close in sequence and in COM
bination according to the characters
gives a brief interval of complete
circuit connection.
The plnter mechanism is con-
| trolled by the operation of an arma- :
ture attracted in a sequence of in
! tervals by magnet coils forming part
of the unit, whereby a chain of
; events takes place. resulting in the
positioning of a type-wheel in proper
i relation for printing a character rep
resented by the energization impart-
| ed to the magnets.
| For radio transmission. the tele-
/ type keyboard mechanism is asSocia-
ted with the radio transmitting cir
cults in such way that the trans
mitter contacts of the keyboard con-
troll the closing and opening of the
radio circuits. and hence the radia-
ton of impulses from he radio anten-
ma system.