Field artillery materiel

by Unknown

In each battalion (F. A.) there are a radio officer, telephone officer, and enlisted personnel for the maintenance of the communication system.

The Camp Telephone.

This telephone, which supersedes the field telephone, was developed by the Signal Corps for use in connection with camp telephone systems and small arms target range systems, and may be installed in tents and structures, or considered a portable instrument for use in the field for testing lines or other purposes. It is of local battery type. The battery employed is one unit of Tungston Type A which is made up of two small cells so placed in a rigid paper that they are connected in series. The combination gives a total voltage of 3—1½ being normal voltage of each cell. The instrument is made as compact as practicable and is contained in an oak case 4¼ × 7 × 10” high. The top consists of a metal hinged cover with circuit diagram on inside, held rigid when closed by a spring snap which can be readily released by depressing a button. The bottom of the case is covered by a flanged piece of metal, the flange projecting approximately one-half inch up sides of case. Through one side of the case are six three-eighths inch holes which are covered on the outside by a close mesh metal screen held in place by a metal frame. These apertures are for the purpose of allowing the ringer to be distinctly heard. The case is equipped with a substantial, adjustable carrying strap, each end of which is fastened to the case by means of hinged metal rings. A small 3-bar magneto generator, small ringer, induction coil, aluminum chamber for the single unit of tungston Type A dry battery, hard rubber block upon which are mounted line binding posts, plug connections for the handset used with the instrument, hook switch and hook operating it and auxiliary battery binding posts, are all mounted on a common base which may be readily removed from case after removing magneto generator crank, metal housing for it and three screws which extend through the case. The instrument may be operated with cover closed which is highly advantageous in inclement weather. To accomplish this there is a suitable opening for leading out the 3-conductor cord to receiver and transmitter, the two latter being mounted in the form of a unit, termed a handset. This handset consists of a transmitter and a receiver mounted on a metal piece and is so designed that when the transmitter is normally placed to the mouth, the receiver is automatically adjusted to the ear. The hook of hook switch is so designed that it protrudes through the case. When it is desired to transport the instrument or to remove the base upon which is mounted all parts of the instrument, it is merely necessary to depress the hook and push it toward the base. By this arrangement the hook is not only held in the down position thereby opening the battery circuit, but it is also protected. The aluminum chamber for housing the single unit of tungston type A battery is equipped with a spring catch so located that when upper hinged piece is depressed to proper position, the battery compresses a helical spring, thereby insuring continual contact. The base is equipped with two screw binding posts which may be used to connect leads to an outside battery in the event of there being no tungston type A batteries available. An aluminum frame which is supported on the base previously mentioned forms a compartment for the handset when instrument is being transported. When the instrument is installed for a temporary period, unless in actual operation, the proper place for the handset is hanging on hook of hook switch, there being a ring on the handset for this purpose. A small screwdriver which will fit practically all the screws used in the construction of the instrument is supported by the metal frame and is furnished with each instrument. The instrument complete weighs about 11 pounds.

THE CAMP TELEPHONE.

CAMP TELEPHONE WIRING.

The Monocord Switchboard.

The liaison of telephone intercommunication between army units is frequently such that a temporary, quickly installed and flexible type of small central exchange located in the field, is essential. Such an exchange is usually placed in a well protected dugout at the infantry battalion headquarters, artillery battalion headquarters, central artillery observation post, etc., where it will be the central terminal point of from four to twelve or more lines connecting with the headquarters of the higher command, with the several units working with the battalion, and with the joining similar battalions. The switchboard which has been designed to meet these requirements is called the “monocord switchboard” and is made up of either four, eight or twelve of the type EE-2 switchboard units.

The monocord switchboard is made up of unit panels, on each of which is mounted all the apparatus needed for the central exchange end of one telephone line. These panels are made of insulating material and are mounted in special wooden frames in groups of four, eight and twelve units, according to the size of the installation necessary. The two sizes most commonly used in overseas work are the four unit and twelve unit boards. Each unit is removable from the frame, thereby lending flexibility to the board and facilitating repair and replacement. Generally, this type of board is used only for a small number of lines as the operating facilities do not permit speedy connections, and it is always better practice to use only three lines on a four unit board and 11 lines on a twelve unit board in order to have a spare unit immediately available.