Artists may come who will portray the marvel of the wires that quiver with electrified words, and the romance of the switchboards that tremble with the secrets of a great city.
As the final result of all these varying changes inswitchboards and signals and batteries, there grew up the modern Telephone Exchange.
The first of these centralizing switchboardswas put in place at Philadelphia; and other cities followed suit as fast as they could afford the expense of rebuilding.
It would compel the rebuild-ing of the switchboards and the invention of new signal systems.
It would make two-thirds of the telephones, cables, and switchboards of all countries.
And here, too, were many of the ablest inventors and engineers, who did most to develop the cables and switchboards of to-day.
Since then, there have come some switchboards that are wholly automatic.
It goes without saying that the building must be large enough to accommodate the switchboards and other apparatus that is required to be installed.
However, switchboards are sometimes manufactured in which the transfer system is included as a part of the original equipment.
Strip of Relays] A bank of line relays especially adapted for small common-battery switchboards as made by the Dean Company, is shown in Fig.
Why are the A and B switchboards in large exchanges entirely separated?
Switchboards having hundreds of thousands of jacks are not uncommon.
Private branch switchboards may be of common-battery or magneto types regardless of whether they work in conjunction with main office equipments having common-battery or magneto equipments.
In larger switchboards the hand generators are entirely dispensed with.
It is customary to handle particular party calls on long-distance switchboards and to handle two-number calls in manual systems on subscribers' switchboards exactly like local calls, except that the two-number calls are ticketed.
The real field of utility for the transfer system today is to provide for the growth of simple switchboards that have extended beyond their originally intended limits.
The provision for proper working of trunk circuits in connection with the two-wire multiple switchboards is not an altogether easy matter, owing particularly to the smaller number of wires available in the plug circuits.
A great part of the wiring of switchboards requires to be done with insulated wires grouped into cables.
In all modern multiple switchboards the test thimble or sleeve contacts are drawn up from sheet brass or German silver into tubular form and inserted in properly spaced borings in strips of hard rubber forming the faces of the jacks.
We have Oswerlander onSwitchboards and Carbon Transmitters.
One of those Juvenile books with simple diagrams and switchboards or junction-boxes.
The development of the switchboards had been comparatively slow in the past, and the service rendered by the boys proved far from satisfactory.
As Mr. Carty himself puts it: The little switchboards of that day were a good deal like the automobiles of some years ago--one was likely to spend more time under the switchboard than, sitting at it!
Scribner devoted himself almost exclusively to switchboards and came to be known as the father of the modern switchboard.
Most of the largeswitchboards of that time were installed under his direction, and they were better switchboards than had ever been known before.
They are used mostly in connection with motors and on switchboards of isolated plants.
Much commercial cable for connecting congested centers with branch switchboards was also required.
There are usually several panels comprising switchboards of moderate or large size, these panels being classified according to the division of the system that they control, as for instance: 1.
On some switchboards are also mounted small transformers for raising or lowering the voltages, and lightning arresters as a protection from lightning.
In addition to the apparatus previously mentioned nearly all switchboards carry at or near their top two or more incandescent lamps provided with shades or reflectors, for lighting the board.
Ordinarily, switchboards vary from five to eight feet in height and the widths of the panels vary from five to six feet.
The different forms of standard alternating current switchboard panels for single phase circuits made by the Fort Wayne Electric Works are designed to fulfill all the usual requirements of switchboards for this class of work.
Put the batteries under automatic switchboards out of commission by dropping nails, metal filings, or coins into the cells.
Switches, Signals and Routing (1) Exchange wires in switchboards containing signals and switches, so that they connect to the wrong terminals.
Molding and conduit work are given careful consideration; and switchboards are systematically treated, built up and illustrated, showing the purpose they serve, for connection with the circuits, and to shunt and compound wound machines.
The line signal in magneto switchboards is practically always in the form of an electromagnetic annunciator or drop.
Thus, entirely irrespective of whether the switchboards are adapted to serve common-battery or local-battery lines, we may have non-multiple switchboards and multiple switchboards.
As already stated those switchboards which are adapted to work in conjunction with magneto telephones are called magneto switchboards.
While great improvement has resulted, the fact remains that the cords of manual switchboards are today probably the most troublesome element, and they need constant attention and repairs.
In still another way we may classify manual switchboards if the method of distributing the energy for talking and signaling purposes is ignored.
These grounded-circuit switchboards provided but a single contact in the jack and a single contact on the plug, the cords having but a single strand reaching from one plug to the other.
Other important elements of manual switchboards are ringing and listening keys.
In such switchboards an operator at one of the boards or positions may complete the connection herself between any two lines terminating at her own board.
Sectional Switchboard--Wall Type] This line ofswitchboards is illustrated in Figs.
There is still another class of manual switchboards called the toll board of which it will be necessary to treat.
A correct idea of the fundamental principle involved in these may be had by imagining a row of simple switchboards each containing terminals or jacks for its own group of lines.
Before considering further the operation of manual switchboards it will be well to refer briefly to the component pieces of apparatus which go to make up a switchboard.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "switchboards" in a variety of sentences. We hope that you will now be able to make sentences using this word.
