The Providence news. (Providence [R.I.]) 1891-1906, 1905-08-21
CRANKS
TO DISAPPEAR
~
Magnetic Switchboard Discarded
Yesterday.
NEW COMMON BATTERY BOARD
All One VIII Have 10 % 10 Get "Centrap'
VIII Be 10 Take Down the
Receiver.

In a few days the telephone cranks OF
this city will have disappeared-that Is
those on the sides Of the telephone boxes
which have been Indispensable in calling
up Central"
All one will have 10 do is to take the
receiver down and instant connections are
established with Central Pawtucket
folk and others who have been out OF
the crank habit for some time will
have a chance TO laugh al their Provi-
dence friends paving from force OF habit
for things which are not.
Yesterday the old magnetic switch board
was discarded for the new common bat
terry board. and today the work OF re-
moving cranks from the instruments OF
subscribers and testing the apparatus will
be commenced. This will be followed by
the replacement OF the old telephones
with instruments similar 10 those con-
nected with the Angel. Broad and West
exchanges, which have the common bat
terry system adopted throughout the
country by progressive companies.
The new board, which extends across
the Union street end OF the telephone
building and along the south side OF the
room is wired for 400 subscribers lines
and has a maximum capacity OF $500 lines.
which. with 400 trunk lines, bring the total
number OF lines up TO 10000 Under pres
ent conditions the board requires 10
operators, and an idea OF its complicated
construction may be formed from the
statement that II contains 1000 miles OF
wire and 25O0O miles Of silk and cotton
thread are wrapped around the wire. The
extent of the labor involved in It's cree
ton Is Indicated by the use OF 1000 900
soldered parts and wiring for 1900 lamps
not larger than the end Of a lead pencil.
The immense number Of parts and
delcacy Of construction make a switch
board approximately 30 feet long and six
feet high as expensive as a modern busi-
ness block The cost of the new board
probably was not less, than $40 900.
The replacing of the magnetic switch
board In the Providence Telephone COM
pany's union office with one OF the latest
type operating on what is called the COM
mon battery system should give this city
the benefit OF every Improvement that has
been made in the art OF telephony as a
result of 30 years OF constant develop
ment The magnetic switchboard was in
universal use until a few years ago, when
the common battery board was invented
by one Of the Bell engineers. With a
magnetic board IL Is necessary 70 place
battery cells upon the premises OF every
subscriber To call central a crank AZ
the side OF the telephone was turned and
the falling OF n numbered drop on the
switchboard I'm the central office signalled
the operator In the common battery
switchboard. as its name indicates, the
batteries for the entire system are con-
centrated In the central office; all the
current for signalling and taking on all
the lines is produced by a storage bat
terry I'm the exchange building. The COM
man battery board not only does away
with the batteries on the subscribers
premises. but makes 1t possible TO signal
central simply by lifting the receiver
OF the telephone instrument from the
hook on which Il hangs when not In use
This action closes the signal circuit
which lights a tiny electric lamp just
above the subscribers calling Jack OF
switch socket I'm the switchboard. There
are thousands of these small signal lamps
and they are much better than the drops
in the old type OF board The lamps
each no bigger than the end of lead
pencil. take very little room compared tc
that required by the drops, and there Is
a great saving Of time. because the
signals OF the flashing lights are more
quickly understood than those given by
the falling shutters